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THE AM BULLETIN BOARD => Technical Forum => Topic started by: n2len on March 15, 2011, 09:13:25 AM



Title: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 15, 2011, 09:13:25 AM
Hello Everyone,
I am looking for recommendations....

I am about to aquire a Hallicrafters SX-88. (serial is very low 200's) Don't know if there were upgrades during the 500 production run.
The unit is in good working condition however it will need a cap/resistor changeout in the future (after my invader restore) in a couple of months.
As far as cosmetics, it needs an overhaul. The bezel suffers from the common warp problem, The panel will need paint/screening or replacement, same goes for the cabinet, and correct knobs.

I would like to know if anyone here has specifically taken on a SX-88 restoration?
Which type of caps to use for switchout, drive belt replacement, circuit upgrades, suggestions regarding disassembly.

I have been searching around the internet for the last week. It seems as though there was a gentleman who sold replica bezels for $230, It was Hank Arney KN6DI. This was back in 2004.
I do remember seeing a Fleabay auction with a guy selling his "Last" replica SX-88 front panel about a year ago.

All suggestions for restoring this Jewel back to it's 1954 Glory is welcomed!

Regards,
Len N2LEN



Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Pete, WA2CWA on March 15, 2011, 02:12:23 PM
Here's a discussion about SX-88 restoration with some pictures:
http://antiqueradios.com/forums/viewtopic.php?t=115086&view=next&sid=2c6a08d4738eded4a8bbd9e98b732867


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 15, 2011, 04:17:41 PM
Thank you kindly for the reply Pete.

I did come across that web page while searching the net.

I have received some responses via e-mail regarding the replacement bezel.

However, So far....

I have been unsuccessful with my search to find a replica front panel/silk screen/paint person.

Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 15, 2011, 04:32:45 PM
Good one  I liked the one I had . Someone else liked it more .There is only one "original" finish.  ;)


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Todd, KA1KAQ on March 15, 2011, 04:47:00 PM
The fellow who took over the panel painting and screening from Lynn N0ALO (?) was here in NC, but apparently the biz has disappeared. The panel should be easy enough to do provided you get a good silkscreen made up first.

Hank Arney KN6DI and (I think) Gary Harmon who's K5 call escapes me at the moment made up that batch of bezels some years back. Not 'exact' as far as all the different radius cuts, but very close (and far better than a warped/cracked example). They used cast aluminum as I recall. No idea if any of those are left, but there might be one or two looking for homes still.

It's been a while since I looked closely at the knobs, can't recall if any are specific to that radio only as far as the lettered skirts go. Knowing Hallicrafters, probably not. 'JN has one and is a good one to ask about details.

Good luck with it.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 15, 2011, 05:39:17 PM
Don't carelessly turn the SX-88 upside down on the bench with the case off because you will damage one of the IF transformers, there are a number of SX-88 receivers that suffered this fate.

You will find a number of black beauty caps inside.  The only really difficult area is the 2nd conversion oscillator chassis.  You will need to unsolder several difficult to reach wires in order to remove this sub-chassis, mark the locations carefully before removal.  In addition to the caps you will almost surely find a number of far out of spec resistors.

The only oddball problem with mine was a lead to one RF coil that was passed through the coil terminal, marked with red inspection paint, but never soldered. 

I don't know of any current source for the belt.  K9RJ (SK) had a run produced but those are long gone.  I would love to find a spare.  The receiver will work fine without it but the light shadow mask will no longer follow the band switch.

It is an enjoyable receiver once restored and mine has been very reliable.  It is paired with a Ranger/Desk KW and the Pierson KP-81 below is paired with a Viking 500.  I looked for a SX-88 for many years before finding one.  Mine is one of four originally owned by Bob Denniston who put Clipperton Island on the air in 1954.






Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: K5UJ on March 15, 2011, 06:19:04 PM
That is a nice looking station there Rodger; I wonder how much TVI the Clipperton Is. dxpedition ran into  ;)


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 15, 2011, 07:14:06 PM
Good one  I liked the one I had . Someone else liked it more .There is only one "original" finish.  ;)

Hello Gary,
I agree,
Anyone have a mint NOS SX-88 Front panel?  ;D


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 15, 2011, 07:31:26 PM
The fellow who took over the panel painting and screening from Lynn N0ALO (?) was here in NC, but apparently the biz has disappeared. The panel should be easy enough to do provided you get a good silkscreen made up first.

Hank Arney KN6DI and (I think) Gary Harmon who's K5 call escapes me at the moment made up that batch of bezels some years back. Not 'exact' as far as all the different radius cuts, but very close (and far better than a warped/cracked example). They used cast aluminum as I recall. No idea if any of those are left, but there might be one or two looking for homes still.

It's been a while since I looked closely at the knobs, can't recall if any are specific to that radio only as far as the lettered skirts go. Knowing Hallicrafters, probably not. 'JN has one and is a good one to ask about details.

Good luck with it.

Todd,
Thanks for the reply....You have it all correct!
Actually Gary's call is K5JWK.
Gary called me this morning with an abundance of helpful information. He also game me some direct correspondence to assist with the location of a replacement bezel. I am actually awaiting response back from 2 individuals for the bezel inquiry.  (A true ham)! Regarding the front panel, several attempts at phone calls to Mike ended up with disconnected lines.
More specifically with my front panel, I am not sure if the panel is an actual SX-88 panel.
If it is, it has been totally stripped, but it appears to be gold anodized?
Would you or anyone take a close look at the picture for your determination at panel originality?
Maybe spray paint. I don't have the receiver in my possession yet. (Actually in transit)

Regarding the knobs, and everything else, I am on a SX-88 Mission!
Thanks for the detailed reply!
All the best....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 15, 2011, 07:59:45 PM
Don't carelessly turn the SX-88 upside down on the bench with the case off because you will damage one of the IF transformers, there are a number of SX-88 receivers that suffered this fate.

You will find a number of black beauty caps inside.  The only really difficult area is the 2nd conversion oscillator chassis.  You will need to unsolder several difficult to reach wires in order to remove this sub-chassis, mark the locations carefully before removal.  In addition to the caps you will almost surely find a number of far out of spec resistors.

The only oddball problem with mine was a lead to one RF coil that was passed through the coil terminal, marked with red inspection paint, but never soldered. 

I don't know of any current source for the belt.  K9RJ (SK) had a run produced but those are long gone.  I would love to find a spare.  The receiver will work fine without it but the light shadow mask will no longer follow the band switch.

It is an enjoyable receiver once restored and mine has been very reliable.  It is paired with a Ranger/Desk KW and the Pierson KP-81 below is paired with a Viking 500.  I looked for a SX-88 for many years before finding one.  Mine is one of four originally owned by Bob Denniston who put Clipperton Island on the air in 1954.





Thanks for the reply Roger....
First off, I love that shack picture!
To tell you the truth,
I am still in total shock that I finally found a fine working SX-88.
I am sure you know that prices are all over the clock on these things....

I will follow your advice on the 50 or so capacitors and resistors!
Did the guy who owned the Belt company (Al from www.Adamsradio.com) ever complete reproducing a actual SX-88 replacement? If I read correctly, someone supplied him with a sample....

I will probably send him an e-mail...

Len,



Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 15, 2011, 08:39:10 PM
Len,

If you find a source for the belt please let me know!  I am a bit nervous when I change bands :)  There was an ER article that talked about making a replacement from piano wire, any port in a storm.

It has been several years since I went through my SX-88 but if you have any questions when you get into yours I will try to address them.   I made a couple of wooden "legs" to support my SX-88 when it was upside down. 

If you don't already have a signal generator that goes down to 50 Khz, start looking for one.  The final IF alignment is critical for best performance and you need a 50 Khz. generator to do it right.  If you have an audio frequency generator see how high it goes, before I bought the external down converter for my HP-8640B I used my very vintage HP audio oscillator which covered up to 200 Khz. on the high end.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: w3jn on March 15, 2011, 11:27:41 PM
I echo Rodger's comments.  Don't put the receiver on its left side, either, because you will be sure to break the IF transformers.

Per the belt, at a surplus store in Minneapolis I found a box of cogged belts that were surplus from copiers or something.  I picked out a few likely suspects and lo and behold one was the right tooth pitch but was about 1/2" too short and too wide.  The width issue was solved by slicing it down its middle with a razor blade; the length issue resolved by loosening all the idlers and shafts and re-tightening them with the belt in place.  I now have a spare, too  ;D

The hunt for knobs will certainly be interesting!  Good luck, Len!


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 16, 2011, 06:25:49 AM
Good one  I liked the one I had . Someone else liked it more .There is only one "original" finish.  ;)

Hello Gary,
I agree,
Anyone have a mint NOS SX-88 Front panel?  ;D

I hear you, the dividing line between preserve and restore.They don't have to be mint to work well.  ;)
 Different folks place different weights on the two. I used to want to take everything back to day one. Lately I have taken more interest in getting the function into top shape whilst cleaning up and preserving as much of the original finish as possible. Different philosophies for everyone. I get a bigger charge out of a well preserved original than anything that even hints of refinishing. In the end , the owner must decide  .In too many cases the previous owners may have already made a big enough mess  that a refinishing job is about the only option. Looks like you are there ! Either way, the SX-88 is a real fine catch, congrats.
 You may find that a good RP shop can make up a very nice plastic bezel for you.  You could also have a 3D working model or pattern made and hand lay a good looking fiberglass replacement. In the concept car business we often made parts like this with fibreglass.  The glass of course is far more stable than the Halliplastic and should hold up for years.
  


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: K5UJ on March 16, 2011, 06:54:38 AM
Bob W0YVA does HT-20 front panels.   Maybe he also refurbs SX-88s.  Might not hurt to ask.  You have to get it separate from the bezel.  I see your bezel warped.  I had that happen on my HT-20.  For now I'm just going to run it without the bezel as mine is so warped and cracked it actually looks better without it.  Unfortunately the SX-88 bezel goes all the way across the front.   :-[  I learned from Rodger that if you encounter a stuck set screw on a knob, drop a bit of oil down the hole and let it set for a day.  If your f.p. isn't too bad maybe you don't have to have it redone.  On the HT-20 here the paint was peeling off and it looked like hell.  One other thing, somewhere on this site there's instructions by JN on how to redo the Hallicrafters gray/black cabinets.  

oops, just saw the front panel--yeah if you don't like that look get the bead blaster ready


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 09:01:04 AM
Len,

If you find a source for the belt please let me know!  I am a bit nervous when I change bands :)  There was an ER article that talked about making a replacement from piano wire, any port in a storm.

It has been several years since I went through my SX-88 but if you have any questions when you get into yours I will try to address them.   I made a couple of wooden "legs" to support my SX-88 when it was upside down. 

If you don't already have a signal generator that goes down to 50 Khz, start looking for one.  The final IF alignment is critical for best performance and you need a 50 Khz. generator to do it right.  If you have an audio frequency generator see how high it goes, before I bought the external down converter for my HP-8640B I used my very vintage HP audio oscillator which covered up to 200 Khz. on the high end.

Regarding the belt....
I sure will!
Is there a way to locate that ER article? Would be fun reading..... ;D
I would have to look at my Marconi to see if the signal generator goes down to 50 KHz.
However, if not a friend offered to align it for me after the cap/resist refresh.
Wooden legs... To hold it up on an angle while working on it?

You see, this is still quite new to me, I'm a repeater man...

Thank you for the offer of assistance. I will probably take you up on that.
Everyone did, when I pulled the front panel off the Viking 500 to restring the band switch!

Regards,
Len

 


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 09:09:26 AM
I echo Rodger's comments.  Don't put the receiver on its left side, either, because you will be sure to break the IF transformers.

Per the belt, at a surplus store in Minneapolis I found a box of cogged belts that were surplus from copiers or something.  I picked out a few likely suspects and lo and behold one was the right tooth pitch but was about 1/2" too short and too wide.  The width issue was solved by slicing it down its middle with a razor blade; the length issue resolved by loosening all the idlers and shafts and re-tightening them with the belt in place.  I now have a spare, too  ;D

The hunt for knobs will certainly be interesting!  Good luck, Len!

Hey John,
Thanks for the input!
I love reading this stuff....I did read your belt find....
Fantastic job, to get you up and running, and now with a spare! ;D

Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 09:49:13 AM
Good one  I liked the one I had . Someone else liked it more .There is only one "original" finish.  ;)

Hello Gary,
I agree,
Anyone have a mint NOS SX-88 Front panel?  ;D

I hear you, the dividing line between preserve and restore.They don't have to be mint to work well.  ;)
 Different folks place different weights on the two. I used to want to take everything back to day one. Lately I have taken more interest in getting the function into top shape whilst cleaning up and preserving as much of the original finish as possible. Different philosophies for everyone. I get a bigger charge out of a well preserved original than anything that even hints of refinishing. In the end , the owner must decide  .In too many cases the previous owners may have already made a big enough mess  that a refinishing job is about the only option. Looks like you are there ! Either way, the SX-88 is a real fine catch, congrats.
 You may find that a good RP shop can make up a very nice plastic bezel for you.  You could also have a 3D working model or pattern made and hand lay a good looking fiberglass replacement. In the concept car business we often made parts like this with fibreglass.  The glass of course is far more stable than the Halliplastic and should hold up for years.
  

I completely agree!
There is nothing better than the original deep dark looking Patina from the original finish.
Yup....With this rig, the only option is a complete cosmetic overhaul...
Interesting idea on the fiberglass replacement, I would still need a complete original panel for the artwork?
When I look at the pictures, it appears that the panel maybe original from the cut out pattern for the 5 switches
in the center...

I should be able to verify this after it arrives tomorrow....

Len





Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 09:54:03 AM
Bob W0YVA does HT-20 front panels.   Maybe he also refurbs SX-88s.  Might not hurt to ask.  You have to get it separate from the bezel.  I see your bezel warped.  I had that happen on my HT-20.  For now I'm just going to run it without the bezel as mine is so warped and cracked it actually looks better without it.  Unfortunately the SX-88 bezel goes all the way across the front.   :-[  I learned from Rodger that if you encounter a stuck set screw on a knob, drop a bit of oil down the hole and let it set for a day.  If your f.p. isn't too bad maybe you don't have to have it redone.  On the HT-20 here the paint was peeling off and it looked like hell.  One other thing, somewhere on this site there's instructions by JN on how to redo the Hallicrafters gray/black cabinets. 

Hello Robert,
Thank you for your reply and suggestions. I will send Bob an e-mail and ask....
I will follow your advice with the "stuck screw set on a knob"!
Yup the front panel, entire cabinet, bezel, knobs, etc., all need to either be changed or replaced with replicas.....

Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 16, 2011, 11:02:59 AM
Good one  I liked the one I had . Someone else liked it more .There is only one "original" finish.  ;)

Hello Gary,
I agree,
Anyone have a mint NOS SX-88 Front panel?  ;D

I hear you, the dividing line between preserve and restore.They don't have to be mint to work well.  ;)
 Different folks place different weights on the two. I used to want to take everything back to day one. Lately I have taken more interest in getting the function into top shape whilst cleaning up and preserving as much of the original finish as possible. Different philosophies for everyone. I get a bigger charge out of a well preserved original than anything that even hints of refinishing. In the end , the owner must decide  .In too many cases the previous owners may have already made a big enough mess  that a refinishing job is about the only option. Looks like you are there ! Either way, the SX-88 is a real fine catch, congrats.
 You may find that a good RP shop can make up a very nice plastic bezel for you.  You could also have a 3D working model or pattern made and hand lay a good looking fiberglass replacement. In the concept car business we often made parts like this with fibreglass.  The glass of course is far more stable than the Halliplastic and should hold up for years.
  

I completely agree!
There is nothing better than the original deep dark looking Patina from the original finish.
Yup....With this rig, the only option is a complete cosmetic overhaul...
Interesting idea on the fiberglass replacement, I would still need a complete original panel for the artwork?
When I look at the pictures, it appears that the panel maybe original from the cut out pattern for the 5 switches
in the center...

I should be able to verify this after it arrives tomorrow....

Len





 While a good original would be the first choice, an artful wood pattern maker could do a credible job from what you may have , along with some photos. Make up a wood positive and pull a glass or plaster mold from that "plug" Use the mold for a lay up. If there are studs or tapped bushing, they can be fixtured into place. An experienced model maker will know just what needs to be done.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: w3jn on March 16, 2011, 11:49:35 AM
Hallicrafters gray/black cabinets:  Semi gloss rustoleum for the black part.  The cabinet top can be painted with a GMC truck DupliColor pewter or silver gray (can't remember which I used now) which is a very close match.  Spray bomb silver is way too bright.  The DupliColor's tone is almost exact but it of course has little flakes in it that the original doesn't have, so a close eye can tell the difference.

Key to success is a lot of prep work.  Sand it well, make sure all scratches are sanded smooth.  Wash a couple times using mild detergent.  Use a tack rag, then prime with gray.  Sand with wet 400 grit.  Clean.  Tack rag.  Another coat of primer.  Sand (wet 600 grit this time), clean, tack rag.  If it's smooth as a baby's bottom by this time, do the black (or silver gray, depending upon the piece you're painting).  Sand, clean, tack rag, then the final coat. 

If it'll fit in your oven, bake it at 180 degrees between coats.  There'll be hell to pay with the war department but the finish will be good and tough.



Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 12:08:43 PM
Hallicrafters gray/black cabinets:  Semi gloss rustoleum for the black part.  The cabinet top can be painted with a GMC truck DupliColor pewter or silver gray (can't remember which I used now) which is a very close match.  Spray bomb silver is way too bright.  The DupliColor's tone is almost exact but it of course has little flakes in it that the original doesn't have, so a close eye can tell the difference.

Key to success is a lot of prep work.  Sand it well, make sure all scratches are sanded smooth.  Wash a couple times using mild detergent.  Use a tack rag, then prime with gray.  Sand with wet 400 grit.  Clean.  Tack rag.  Another coat of primer.  Sand (wet 600 grit this time), clean, tack rag.  If it's smooth as a baby's bottom by this time, do the black (or silver gray, depending upon the piece you're painting).  Sand, clean, tack rag, then the final coat. 

If it'll fit in your oven, bake it at 180 degrees between coats.  There'll be hell to pay with the war department but the finish will be good and tough.


John...Some further questions....
When you stripped the cabinet, Do you remember if the color of the aluminum was anodized gold or silver?
Is the grey/black color of the SX88 the same as the SX101?
When I receive the SX88 tomorrow, it will unveil some questions regarding the originality of the front panel and if the cabinet was painted gold.

Much thanks again!


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Todd, KA1KAQ on March 16, 2011, 12:29:37 PM
Definitely not an original finished panel if you're still wondering on that, Len. Looks like someone had it anodized and applied some P-Touch labels to a few controls. The rest are blank, labels were on the knob skirts for many.

Should be a typical Halli gray panel with white lettering and trim around the switches. Maybe Rodger can give you a good close up shot of his to give you a good idea where to start.

I'd say if you get a replacement bezel and get the front panel repainted, that would be more than half the battle. Knobs will be a challenge, but some at least may well be shared with a few other sets like the SX-62, SX-42, etc. that also used the labeled aluminum skirts. You've got the two main tuning knobs which is a big plus, they're probably the most difficult to find. Halli used them on the SX-73 and R-649, maybe a couple others. I have no idea if any of the small knobs were specific to the 88 only, though I doubt it.

Johnny is right on the money for the black color. If you can't find the silver he suggests, Rustoleum had a good match for the silver cabinet cover too. Can't remember the name/number right now. Seems like it was Dull Aluminum or something along those lines. Not too bright, no shiny bits.

Looks like you've got a excellent foundation for a rebuild. As was mentioned, it may not end up being perfect 'collector quality', but you should come out of it with a nice looking and working set when all is said and done.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: w3jn on March 16, 2011, 02:01:30 PM
The gold lid is a hammy hambone addition, too.  All Hallicrafters cabinets in that style had basically the same paint - black cabinet with a silver lid.  It's just plain ol' steel underneath.

That cabinet is unique to the SX-88 though, it's deeper than any other Hallicrafters cabinet.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: KC4VWU on March 16, 2011, 02:27:09 PM
This may or may not be helpful on the bezel, but since it looks to only be distorted, you may be able to straighten it if you're very careful.

I did a straightening job on a bezel or "hood, if you will", for a NC-270 once. With a lot of patience, and luck, I got it back straight as an arrow. The main thing to remember is work VERY slowly, over days; weeks, if necessary. Crank a LITTLE pressure, let it stand a day, take it out and re-check it. You'll need a good bench vise and a lot of different shim materials in different sizes, shapes, and material. Don't forget that a little heat in various temps/durations can really help also. The key is VERY SLOW! Also, if it does manage to crack, remember those Wonder Rods they used to advertise on tv that would braze anything? The only 2 times I have seen those actually used, they did work. Once more, VERY SLOWLY.

As it stands, you don't have anything to lose, but don't take that mindset when you start. Think of it as being the last one available. If it is really crappy pot metal, it may be a fruitless exercise, but what the heck?

73, Phil   

 


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: KC4VWU on March 16, 2011, 02:33:30 PM
Also, I forgot to add, JUST IN CASE there is a possibility, make sure it's not made out of magnesium BEFORE you add any flame?
 
73, Phil


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 02:42:27 PM
Definitely not an original finished panel if you're still wondering on that, Len. Looks like someone had it anodized and applied some P-Touch labels to a few controls. The rest are blank, labels were on the knob skirts for many.

Should be a typical Halli gray panel with white lettering and trim around the switches. Maybe Rodger can give you a good close up shot of his to give you a good idea where to start.

I'd say if you get a replacement bezel and get the front panel repainted, that would be more than half the battle. Knobs will be a challenge, but some at least may well be shared with a few other sets like the SX-62, SX-42, etc. that also used the labeled aluminum skirts. You've got the two main tuning knobs which is a big plus, they're probably the most difficult to find. Halli used them on the SX-73 and R-649, maybe a couple others. I have no idea if any of the small knobs were specific to the 88 only, though I doubt it.

Johnny is right on the money for the black color. If you can't find the silver he suggests, Rustoleum had a good match for the silver cabinet cover too. Can't remember the name/number right now. Seems like it was Dull Aluminum or something along those lines. Not too bright, no shiny bits.

Looks like you've got a excellent foundation for a rebuild. As was mentioned, it may not end up being perfect 'collector quality', but you should come out of it with a nice looking and working set when all is said and done.


Hey Todd,
Regarding the front panel, Yup, I agree it looks anodized. which now looking back at the original correspondence from the gentleman I purchased it from mentioned. The front panel and lid are anodized gold.
With the advice of Robert K5UJ and Howard Mills, I reached out to Bob W0YVA. Howard actually got in touch with him which led to a telephone call. After speaking with Bob, he offered the service of repaint/silkscreen the front panel and cabinet as well. You are dead on with the knobs! I'm sure I will be able to muster some hallicrafter knobs from another rig for a closer match. I was thinking of maybe asking Bob to refinish the front panel and I complete the cabinet.  ;D






Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 02:44:04 PM
The gold lid is a hammy hambone addition, too.  All Hallicrafters cabinets in that style had basically the same paint - black cabinet with a silver lid.  It's just plain ol' steel underneath.

That cabinet is unique to the SX-88 though, it's deeper than any other Hallicrafters cabinet.

Yup!
The front panel and lid is gold anodized!


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 02:49:11 PM
This may or may not be helpful on the bezel, but since it looks to only be distorted, you may be able to straighten it if you're very careful.

I did a straightening job on a bezel or "hood, if you will", for a NC-270 once. With a lot of patience, and luck, I got it back straight as an arrow. The main thing to remember is work VERY slowly, over days; weeks, if necessary. Crank a LITTLE pressure, let it stand a day, take it out and re-check it. You'll need a good bench vise and a lot of different shim materials in different sizes, shapes, and material. Don't forget that a little heat in various temps/durations can really help also. The key is VERY SLOW! Also, if it does manage to crack, remember those Wonder Rods they used to advertise on tv that would braze anything? The only 2 times I have seen those actually used, they did work. Once more, VERY SLOWLY.

As it stands, you don't have anything to lose, but don't take that mindset when you start. Think of it as being the last one available. If it is really crappy pot metal, it may be a fruitless exercise, but what the heck?

73, Phil   

 
Phil,
That's fantastic!
You know everyone I spoke to so far....
Said, the bezel will probably crack with any attempt at straightening it back..
Your suggestions sound very promising however, I am not set up with the proper tools to attempt repair.
Would you like to tackle the bezel work for me?

Regards,
Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 16, 2011, 03:26:08 PM
The bandwidth knob (goes from 250 cycles to 10 KC for the SX-88) is unique to this receiver as is the actual frequency band around the band switch knob but the knob style itself is common to other Halli gear.  Other knobs are common to a lot of Halli gear and you can probably live with a close match from another receiver for the bandwidth knob. 

As long as your belt doesn't break, you won't need the frequency markings on the band switch knob :)


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 05:20:45 PM
The bandwidth knob (goes from 250 cycles to 10 KC for the SX-88) is unique to this receiver as is the actual frequency band around the band switch knob but the knob style itself is common to other Halli gear.  Other knobs are common to a lot of Halli gear and you can probably live with a close match from another receiver for the bandwidth knob. 

As long as your belt doesn't break, you won't need the frequency markings on the band switch knob :)

I guess I will just check around for some similar knobs for replacement....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Todd, KA1KAQ on March 16, 2011, 06:14:43 PM
Rodger's input on the band switch knob is great, because it's the same knob used on the SX-42, HT-32/33 and maybe a couple others. I just sold one along with a full set of SX-42 knobs (probably some of the ones you need!) last fall. Held onto them for years, no one needed them, so off to the 'Bay they went.

You'd need to clean and most likely repaint the skirt, then either do an excellent job of re-lettering with dry transfers or maybe make a clear decal you could wrap around the skirt. Ask Bob about this, maybe he already did his over. No need to re-invent the wheel.

Or as Rodger says, just find one with good paint from a SX-42 and stuff it on. Close enough.

I bet Gary will turn up a bezel for you.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WBear2GCR on March 16, 2011, 06:21:43 PM


That "gold anodized" panel may be "Alodine" which is a conversion coating suitable for taking paint. I forget at the moment what the generic coating is called, another CRS moment...


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 07:29:10 PM
Rodger's input on the band switch knob is great, because it's the same knob used on the SX-42, HT-32/33 and maybe a couple others. I just sold one along with a full set of SX-42 knobs (probably some of the ones you need!) last fall. Held onto them for years, no one needed them, so off to the 'Bay they went.

You'd need to clean and most likely repaint the skirt, then either do an excellent job of re-lettering with dry transfers or maybe make a clear decal you could wrap around the skirt. Ask Bob about this, maybe he already did his over. No need to re-invent the wheel.

Or as Rodger says, just find one with good paint from a SX-42 and stuff it on. Close enough.

I bet Gary will turn up a bezel for you.

Sounds good to me....! ;D
Thanks much for all the advice...
Awaiting on the bezel answer from several people....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 16, 2011, 07:31:14 PM


That "gold anodized" panel may be "Alodine" which is a conversion coating suitable for taking paint. I forget at the moment what the generic coating is called, another CRS moment...

Thanks for the input!
Will I be able to determine the difference by simply looking at the receiver when it arrives?


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 17, 2011, 09:34:55 PM
The SX-88 arrived late this evening.  It was packaged really well and survived it trip!

I couldn't resist! So I immediately began to break it down.

Initial inspection, show 2 IF cans in the left corner need repit work. They snapped off the left sided rivets! Quite apparently from prior sitting on it's left side!
Suggestion to repair? I've seen many for sale with the same repair, just by using solder.

Removal of the front panel was easy. It just slipped off the front of the chassis, I just needed to remove the panel screws and the nut for the phono jack!

The panel, lid and both band spread knob plates were anodized gold.
I removed the dial glass, and the bezel, the panel is the original and looks like it would be a good candidate for refinishing by Bob!

I haven't given up on the bezel. It's pretty bad, however there has to be some way of straightening it back out, maybe by a aluminum repair shop, with heat.

Sliding the front panel off exposed the complete dial assembly.

Another repair has to be done. Any suggestions on this one?

The right dial pointer cam, the brass wire belt snapped off. Someone used silicone glue to hold the dial pointer straight up!

Further primary inspection revealed a pretty clean chassis, with what looks to be a good drive belt, under-body shows many capacitors changed.

Any suggestions please....
Some pictures to follow....
 



Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 17, 2011, 09:38:24 PM
more pics


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 17, 2011, 09:41:24 PM
more pics


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 17, 2011, 10:09:30 PM
Len,

It looks like this should turn into a very nice SX-88 when you are through.  I would get the panel and all of the electronic and mechanical problems addressed and then worry about the bezel.

 It has been a very long day but I will try to comment on a possible repair for the pointer drive tomorrow, I wouldn't put a lot of trust in any complex explanations I write tonight.  Someone else may chime in before tomorrow.

One other caution:  I had no problems with seized adjusting hardware with any of the IF transformer adjustments with my SX-88 and you probably will not with yours.  But if you do, proceed with extreme caution as the low IF transformers in the SX-88 are exclusive to this receiver so another SX-88 is the only source for a proper spare.  Although it would limp along with a replacement transformer out of another one of the Halli 50 KC low IF receivers (SX-96, 100, 101, 111, 115, 117) the SX-88 IF transformers have significantly higher Q and the difference is evident in a side by side comparison with the later family members. 


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Todd, KA1KAQ on March 17, 2011, 10:10:11 PM
Wowsers, Len. It actually looks to be in pretty clean shape overall. And someone has re-capped it already, though you might want to re-check and redress the work.

Basically, once Bob repaints the panel for you and you get the cabinet done, all you'll need to deal with is the bezel and knobs, bolt-on parts. Not bad.

I have a bad feeling you won't have much luck straightening that bezel. Even if you could get the main sag out of it, the other waves would still be obvious. Though it might be a bit on the costly side, if you can't get one of the replacement bezels through Gary, perhaps you could get one machined locally. In fact, it might be an excellent project for a local shop class to undertake.

Keep us posted on your progress. And watch ebay for SX-42 knobs or a beater parts set as well as putting out the word here and elsewhere.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: W2XR on March 17, 2011, 10:36:12 PM


That "gold anodized" panel may be "Alodine" which is a conversion coating suitable for taking paint. I forget at the moment what the generic coating is called, another CRS moment...

Hi Bear,

Perhaps you are referring to irridite chemical film treatment?

You and I have both had a lot of experience with irriditing and re-irriditing aluminum components.

73,

Bruce


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 18, 2011, 06:27:40 AM
Alodine (a conversion coating process similar to Iridite) leaves a gold tone finish on aluminum. "Metal-Prep" often leaves a yellowish looking phosphate coating on steel . Both are good substrates for paint.  There are a few replacements for cadmium plating now in use for steel finishing that leave a yellowish sheen. Zinc Dichromate is but one of the Cad plate alternatives.
 "Aircraft Spruce and Specialty" handles many products for finishing and preserving metals along with great metalworking  tools and supplies. A request will bring a catalog.
 For the rattle can painters; An alternative to flat black Rustoleum paint is Krylon "Chalkboard" black. Not as chalky as one would think. A very durable semi-flat furface.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 08:24:25 AM
Len,

It looks like this should turn into a very nice SX-88 when you are through.  I would get the panel and all of the electronic and mechanical problems addressed and then worry about the bezel.

 It has been a very long day but I will try to comment on a possible repair for the pointer drive tomorrow, I wouldn't put a lot of trust in any complex explanations I write tonight.  Someone else may chime in before tomorrow.

One other caution:  I had no problems with seized adjusting hardware with any of the IF transformer adjustments with my SX-88 and you probably will not with yours.  But if you do, proceed with extreme caution as the low IF transformers in the SX-88 are exclusive to this receiver so another SX-88 is the only source for a proper spare.  Although it would limp along with a replacement transformer out of another one of the Halli 50 KC low IF receivers (SX-96, 100, 101, 111, 115, 117) the SX-88 IF transformers have significantly higher Q and the difference is evident in a side by side comparison with the later family members. 

Thanks much for the reply....
I am awaiting you comment on repair of the pointer drive.  Upon close examination of the pointer cam, the silicone used will first
have to be completely removed. That should hopefully peel off.
Regarding the 2 IF cans on the left back side, Is the soldering method the best at repair? Basically soldering the rivet to the actual can itself? If so, Would applying heat from the solder gun possibly damage the IF can in anyway?


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 08:35:14 AM
Wowsers, Len. It actually looks to be in pretty clean shape overall. And someone has re-capped it already, though you might want to re-check and redress the work.

Basically, once Bob repaints the panel for you and you get the cabinet done, all you'll need to deal with is the bezel and knobs, bolt-on parts. Not bad.

I have a bad feeling you won't have much luck straightening that bezel. Even if you could get the main sag out of it, the other waves would still be obvious. Though it might be a bit on the costly side, if you can't get one of the replacement bezels through Gary, perhaps you could get one machined locally. In fact, it might be an excellent project for a local shop class to undertake.

Keep us posted on your progress. And watch ebay for SX-42 knobs or a beater parts set as well as putting out the word here and elsewhere.

Thanks Todd,
Actually I'm thrilled....I really can't believe it's actually here....In person....What a freaking sickness this hobby is heh'?
The gentleman who I got it from, took extreme care packaging it for me and it paid off when it arrived.
Yup, I will go through the capacitor work touching up anything found if necessary. You know, regarding the bezel, I looked at it more closely last night, where it warped shows many tiny stress cracks. The composite metal makeup resembles a fishing lead anchor. (well maybe not) but more lead looking than aluminum.
Hopefully, a replacement bezel will come up somewhere. Gary, put me in contact with a gentleman in NYC who purchased a lot of these bezels, maybe he has one to part with...
I also would like to eventually fine a replacement belt....
Looking for the knobs too!

Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 08:40:14 AM
Alodine (a conversion coating process similar to Iridite) leaves a gold tone finish on aluminum. "Metal-Prep" often leaves a yellowish looking phosphate coating on steel . Both are good substrates for paint.  There are a few replacements for cadmium plating now in use for steel finishing that leave a yellowish sheen. Zinc Dichromate is but one of the Cad plate alternatives.
 "Aircraft Spruce and Specialty" handles many products for finishing and preserving metals along with great metalworking  tools and supplies. A request will bring a catalog.
 For the rattle can painters; An alternative to flat black Rustoleum paint is Krylon "Chalkboard" black. Not as chalky as one would think. A very durable semi-flat furface.

Actually the front panel and top lid, are gold....The panel is shiny, smooth, and gold, which may of been buffed during the process.
I would guess it was anodized or even gold plated?  ;D


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 09:55:52 AM
Question to the group...

Reagrding repair of the 2 "IF cans". Looking from the bottom of the cabinet...
It appears as though each can is held in by 2 nuts.
If I remove the nuts from the bottom of the "IF" can will the can simply slip off the slug for repair?


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 18, 2011, 10:07:58 AM

Thanks much for the reply....
I am awaiting you comment on repair of the pointer drive.  Upon close examination of the pointer cam, the silicone used will first
have to be completely removed. That should hopefully peel off.
Regarding the 2 IF cans on the left back side, Is the soldering method the best at repair? Basically soldering the rivet to the actual can itself? If so, Would applying heat from the solder gun possibly damage the IF can in anyway?

If you could, send me some good closeup shots of the pointer drive so that I am sure I understand exactly how it is broken.  

It will take a fair amount of heat and there is no other source of these transformers so there is a definite risk with soldering.  If it were mine, I would try one of the two part epoxy mixes and make a neat repair with it.  Although JB Weld uses a lot of hyperbole in their advertising it is a pretty good product and I have used it for a number of metal repairs.  I wouldn't trust it to repair a cracked engine block as they claim in the advertising but I am confident it would easily handle the much gentler environment of the SX-88.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 10:41:36 AM

Thanks much for the reply....
I am awaiting you comment on repair of the pointer drive.  Upon close examination of the pointer cam, the silicone used will first
have to be completely removed. That should hopefully peel off.
Regarding the 2 IF cans on the left back side, Is the soldering method the best at repair? Basically soldering the rivet to the actual can itself? If so, Would applying heat from the solder gun possibly damage the IF can in anyway?

If you could, send me some good closeup shots of the pointer drive so that I am sure I understand exactly how it is broken.  

It will take a fair amount of heat and there is no other source of these transformers so there is a definite risk with soldering.  If it were mine, I would try one of the two part epoxy mixes and make a neat repair with it.  Although JB Weld uses a lot of hyperbole in their advertising it is a pretty good product and I have used it for a number of metal repairs.  I wouldn't trust it to repair a cracked engine block as they claim in the advertising but I am confident it would easily handle the much gentler environment of the SX-88.

Hey Rodger, Sure....
Here they are....
I took pictures of the left side which is fine to show how it is built. It appears that they used a brass piece the is shaped like a "U". It goes around the bottom brass cam, then each end it attached to the pointer cam on top. How it is attached, I don't know maybe soldered or glued. I need to look closer.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 18, 2011, 10:54:19 AM
Len,

That is what I thought you were describing but I wanted to be sure.

You can make a replacement piece either from brass or copper which should be available at hobby shops.  I would suggest using a very small amount of the same two part epoxy I mentioned earlier to anchor the ends to avoid discoloring the black painted part of the pointer assembly from soldering heat.  The messiest part will be removing the silicone without damaging anything. 

I remember you mentioned some of the under chassis caps were replaced.  You might contact the seller to see if he knows whether the caps in the 2'nd converter assembly were replaced.  You don't want to go through the removal process if you don't have to (but it originally contained black beauties which were cracked in my SX-88 production run 2).

Rodger


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 10:55:41 AM
Now looking at it closer up....All it is....is a brass stick not  "U" shaped. Each side is a straight piece of brass. Attached from the top of the pointer than is just comes down and sits in the lower brass cam. When you turn the knob the cam moves up and down the sticks thus moving the pointer. This should be an easy fix...?
I need to first carefully remove the silicone and figure out what type of metal to use. Maybe I can cut a thick paper clip.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 11:12:37 AM
What Luck...What I thought would be the most difficult part was the easiest...

Would you believe that the silicone came off in one total piece?

Now I can clearly see the brass stick and how it is attached to the pointer wheel. Only the right side broke off. I even checked to see if the broken part was laying inside the receiver. No luck, it's long gone...
It looks like maybe a sewing needle, trimmed to the correct length would fit perfectly.
I think that I may need to remove the front panel to allow me to swing the sticks back on the lower cam after the right side is repaired.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 18, 2011, 11:23:04 AM
I am glad the silicone came off in one piece without taking anything else with it.  The rest should be a simple repair.  One wonders why the person who repaired this didn't do it properly in the first place since it is a fair amount of work to access this part of the receiver. 

Make sure you pair this receiver with a decent speaker to take advantage of its wide bandwidth IF and audio system.  I use a R-42 with mine and it sounds great with good source material. 

I have some additional advertising and other SX-88 related stuff that I will scan for you.  Next week is very busy but after that I will have time to get this stuff to you for your SX-88 collection.



Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 02:24:57 PM
I am glad the silicone came off in one piece without taking anything else with it.  The rest should be a simple repair.  One wonders why the person who repaired this didn't do it properly in the first place since it is a fair amount of work to access this part of the receiver. 

Make sure you pair this receiver with a decent speaker to take advantage of its wide bandwidth IF and audio system.  I use a R-42 with mine and it sounds great with good source material. 

I have some additional advertising and other SX-88 related stuff that I will scan for you.  Next week is very busy but after that I will have time to get this stuff to you for your SX-88 collection.



I am glad as well...I haven't the slightest clue why it wasn't repaired before. The pointer wheel is held on with a very small "C" type clip. If you look at the previous picture you can clearly see it. It is quite tiny. If I was able to remove that clip, then the wheel itself, repair would be very easy with the better results. However, repair while it's in place should work out fine too.

If you reommend the R-42 speaker, then that's what I'll look for.
Any advertising stuff any paper work, color or black & white, please do scan at your convenience. I will gladly pay you for your time and postage.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 08:40:17 PM
Rodger,

I was able to carefully remove the tiny "C" clip using 2 dentist picks. After the clip was removed, The pointer wheel just slid off. I ended up using a sewing needle cut to size then bent at the proper angle. It actually fit into the swell of where the original pin snapped off.  I also took your advice and used JB Kwik Weld for the adhesive. The JB Kwik sets in only 4 minutes, total bond after 4 hours.

Here is a quick picture of the pointer cam and "C" clip.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on March 18, 2011, 09:10:51 PM
Len,

It looks like a  very good repair and the IF transformer repair should be even easier.  You are going to have a great set of before and after restoration photos when you finish this project.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 18, 2011, 09:14:10 PM
Len,

It looks like a  very good repair and the IF transformer repair should be even easier.  You are going to have a great set of before and after restoration photos when you finish this project.

Thanks....
I agree...Tomorrow I will touch up on the pointer wheel, if it needs any further adhesive.
After I re-install it, next will be the IF can repair.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 08:01:41 AM
Right pointer wheel repaired and re-installed.

After the initial JB Kwik adhesive was used. About 4 hours later, I reapplied a little more fanning it out from the bottom with a toothpick. This morning, I simply slipped it back onto it's cam and reapplied the "C" clip. A black felt tip market was used to color the JB weld black.

The only setback was on the first attempt at snapping the "C" ring back, it went "BING" and flew across the room. After about 1 hour of search and rescue, on my knees (with a flashlight) it was recovered.
This thing it TINY!

The pointer control now works perfectly!

Any suggestions to remove the black spray paint that was used to paint the 5 switch levers on the front?


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: aafradio on March 19, 2011, 08:12:28 AM
Any suggestions to remove the black spray paint that was used to paint the 5 switch levers on the front?

Yup - Q-tips and MEK from the paint section of your local home store (except in California, I suspect).  Be sure to do it in a well ventilated area.  MEK isn't the worst of the solvents from a health standpoint, but it is potentially more intrusive than acetone, for example.

To forstall the concerns of some who have not used it, here's a reasonable summary of cautions:  http://www.bfksolutions.com/Newsletter%20Archives/V3-Issue%203/MEK%20No%20Longer%20HAP.html


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 08:28:25 AM
Any suggestions to remove the black spray paint that was used to paint the 5 switch levers on the front?

Yup - Q-tips and MEK from the paint section of your local home store (except in California, I suspect).  Be sure to do it in a well ventilated area.  MEK isn't the worst of the solvents from a health standpoint, but it is potentially more intrusive than acetone, for example.

Thanks,
That was exactly what I was looking for. I'll check Home Depot this afternoon....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 10:25:45 AM
2 Rear Left IF can repair....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 12:45:23 PM
What is the best cleaner polish for aluminum?

I would like to clean and polish the side panels and tube shields...


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: aafradio on March 19, 2011, 01:28:58 PM
It depends on what you mean by polish.  See http://amfone.net/Amforum/index.php?topic=24506.msg182212#msg182212 for a wide ranging discussion of the subject.  ;D


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 19, 2011, 01:42:59 PM
Also, I forgot to add, JUST IN CASE there is a possibility, make sure it's not made out of magnesium BEFORE you add any flame?
 
73, Phil

  Actually , open flames on magnesium parts are no real problem. Although I seriously doubt this is a magnesium part.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: KC4VWU on March 19, 2011, 02:31:09 PM
Len,
        I couldn't possibly get to the task in a timely manner due to all other things going on here besides the big task of moving. Looking through your recent posts though, it seems it's in fragile shape and if the others advised you it wouldn't survive, they would know much better than myself because I don't have any first hand knowledge of the rig.

I agree in that you would probably be much better off to have one made from aluminum if a suitable replacement couldn't be located. Even though it is badly disfigured, it would be much better for the existing bezel to be in one piece so that a machinist could more easily get the measurements he needs.

Another thing that came to mind is casting one from resin (better than nothing at this point) which would also present the problem of needing a good donor to make a mold.

Wasn't too sure of the flammability issues of magnesium, just remember the stories I've heard about the old style mag wheels on cars catching fire. Probably just old wive's tales used to embellish old war stories of drag racing.

73, Phil


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 19, 2011, 04:06:44 PM
You will likely find that a vacum bagged epoxy-glass layup is far more stable than most resin materials . Especially with the long spans and thin sections.  A good pattern maker should be able to make up a suitable form if a decent sample is made available. If I had a bezel you would be welcome to borrow it. Sadly I do not. My buddy up in West Branch MI (Ron Hattner, N8UUH)  has one , maybe I can borrow his and get a pattern made up for you. I will try to speak with him this week end.

  Torches aren't a big issue when working mag alloys. We TIG and Oxy-Acetylene work it often. ;)


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 04:40:51 PM
It depends on what you mean by polish.  See http://amfone.net/Amforum/index.php?topic=24506.msg182212#msg182212 for a wide ranging discussion of the subject.  ;D

Just looking for something to assist with removing the dirt on the chassis with a Q-TIP.
Also a polish for the tube shields...


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 04:42:56 PM
Also, I forgot to add, JUST IN CASE there is a possibility, make sure it's not made out of magnesium BEFORE you add any flame?
 
73, Phil

  Actually , open flames on magnesium parts are no real problem. Although I seriously doubt this is a magnesium part.

Definitely not magnesium... Maybe more like Pot metal...


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 04:46:17 PM
Len,
        I couldn't possibly get to the task in a timely manner due to all other things going on here besides the big task of moving. Looking through your recent posts though, it seems it's in fragile shape and if the others advised you it wouldn't survive, they would know much better than myself because I don't have any first hand knowledge of the rig.

I agree in that you would probably be much better off to have one made from aluminum if a suitable replacement couldn't be located. Even though it is badly disfigured, it would be much better for the existing bezel to be in one piece so that a machinist could more easily get the measurements he needs.

Another thing that came to mind is casting one from resin (better than nothing at this point) which would also present the problem of needing a good donor to make a mold.

Wasn't too sure of the flammability issues of magnesium, just remember the stories I've heard about the old style mag wheels on cars catching fire. Probably just old wive's tales used to embellish old war stories of drag racing.

73, Phil

I'm working on trying to get the original blue prints or if there was a CNC program saved when the original replicas were made.

I was speaking to several friends about the possibility of making a blue print from my bezel.
But I don't have a CAD program to do so....
Maybe someone who does drafting work may be able to assist.
I will take the original bezel over to a machine shop for there evaluation next week,


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 19, 2011, 04:47:30 PM
You will likely find that a vacum bagged epoxy-glass layup is far more stable than most resin materials . Especially with the long spans and thin sections.  A good pattern maker should be able to make up a suitable form if a decent sample is made available. If I had a bezel you would be welcome to borrow it. Sadly I do not. My buddy up in West Branch MI (Ron Hattner, N8UUH)  has one , maybe I can borrow his and get a pattern made up for you. I will try to speak with him this week end.

  Torches aren't a big issue when working mag alloys. We TIG and Oxy-Acetylene work it often. ;)

That would be fantastic if you can possibly do that....!

Anyone on the forum have any friends with a CNC machine? ;D


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WA1KBQ on March 20, 2011, 03:28:41 PM
Congratulations on your recent SX-88 acquisition Len. Whether to restore or not as mentioned earlier in the thread is subject to one's personal views toward historical items but in my opinion the SX-88 should be restored to working order with a good appearance whenever possible. It appears you have a few challenges ahead with your's but basically you have a very good restorable receiver that should yield satisfactory results. I have restored four SX-88s so far and have just recently started on a fifth unit so have accumulated at least some practical experience in the process. I can offer some of the techniques I have found helpful so far.

The bezels were all potmetal with an inconsistent mixture of ingredients so some warped with environmental temperature and humidity changes but many did not. Any attempt to straighten yours will likely result in breakage as decomposed potmetal is very fragile and brittle. Early potmetal was the dross skimmed off the top from refining other metals. I would try to buy the CNC code from Dan Arney and make a few more. A word of caution is possibly in order here though. The original part was a casting and the design included a compound radius inside the picture frame. To accurately duplicate the appearance of the original part by machine you would have to have CNC 5-axis simultaneous capability. Dan's reproduction bezels were run on a 3-axis machining center and while pretty close to the original they do not feature the original part's compound radius in the picture frame inside corners. If you need a bezel they sure beat not having one though and Dan should be recognized for stepping up and making parts available and filling a genuine need.

Paint can be whatever you want it to be but for best appearance results the gray should be a flat gray and the silkscreened nomenclature should be an aged or antique white. You really don't want bright refrigerator white silkscreening on these but that is what most silkscreeners will put on if you don't specify. 

Three of the knobs you need are specific to the SX-88 which are the Band Selector, Response, and Band Width. You could use the SX-42 (or HT-32) Band Selector knob and ignore the nomenclature since it will not match your receiver. The Response and Band Width knobs could be made from  a standard AF/ RF gain knob with a 0-10 skirt with painting and renumbering. All others were used on other Halli models.

It looks like you have the dial pointers fixed already but all they are is brass rods soldered to each side of a brass disc. If the epoxy does not hold you can always solder them later.

Be sure to support the phone jack with a wire tie to the Response control shaft, the leads are solid core and will break away easily moving the chassis around. Not a big deal but saves unnecessary additional work.

This is a receiver that will require extensive recapping if top results are to be realized and you really don't want to disassemble it a second time to revisit things missed during the first attempt. In my experience besides all the plate and screen bypass caps (which are the most critical) you have silver mica tank caps inside each of the 1550/ 2075KC first IF transformers which if left unattended to will likely result in a steady barrage of static crashes and sizzling bacon sounds in the audio. You will also find lots of resistors have drifted far over the high end tolerance range that will need to be replaced. In my estimation an SX-88 receiver will not be ready for alignment unless you have replaced all capacitors in the 1st and 2nd RF stages and 2nd converter deck in addition to all 50KC IF stages and checked and replaced all resistors as necessary.

It is very common to find broken lugs on 50KC IF transformers T-12 and T-13 mounted on the left rear corner of the chassis. Due to the triangular shape of the side brace the chassis will easily roll over and fall before you can catch it when out of the cabinet and stood up on its side. I always remove the side braces anyway and often screw one or both back on backward to use them as temporary chassis stands. If you remove the nuts the IF can will slip off with the coil form left in place but be careful about the clip on top, you don't want to tear the thin bakelite coil form while pulling on the can. You will have to unsolder the lugs anyway to properly recap so you might as well remove the IF transformers anyway. The cans are made of .015 stamped aluminum and .015 aluminum sheet stock is readily available. I always disassemble all IF transformers to check for overheated windings anyway and this is a convenient time to repair any pulled lugs. Straighten the torn aluminum around the lug mounting hole and press flat. Cut a small square of .015 sheet aluminum, punch a hole for the rivet and epoxy to the inside of the can over the affected area, use a C-clamp. When cured I re-rivet the lug to the can but small hardware of the appropriate size would work just as well. Be very careful with those threaded ferrite slugs as they are irreplaceable. Make a proper adjusting tool according to the directions in the instruction manual and don't be tempted to use something that seems to fit. The ferrite on top of the slugs is very thin and will break if the slug is tight and the appropriate tool that fits correctly is not used.

If the previous owner had the 2nd converter sub-chassis off you should see evidence of removed wire leads, there are about 12 of them and access to some is very restricted. Without proper equipment it is difficult to achieve professional looking results removing and reinstalling them and many SX-88s out there right now look like they have obviously been apart.

Regards, Greg


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WA1KBQ on March 20, 2011, 04:21:23 PM
SX-88 Serial #400 currently in process:

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20400/SX88-40023.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20400/SX88-40027.jpg


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WA1KBQ on March 20, 2011, 04:31:21 PM
A brief picture history of other recent SX-88 restoration work:

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3178.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3198.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/444-007.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/444-021.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/444-008.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/446-022.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-009.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-010.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-011.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-012.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-026.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-022.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-023.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-024.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/444-025.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3075.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3076.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3085.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3091.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3099.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3183.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20444/IMG_3182.jpg


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 20, 2011, 09:57:33 PM
Congratulations on your recent SX-88 acquisition Len. Whether to restore or not as mentioned earlier in the thread is subject to one's personal views toward historical items but in my opinion the SX-88 should be restored to working order with a good appearance whenever possible. It appears you have a few challenges ahead with your's but basically you have a very good restorable receiver that should yield satisfactory results. I have restored four SX-88s so far and have just recently started on a fifth unit so have accumulated at least some practical experience in the process. I can offer some of the techniques I have found helpful so far.

The bezels were all potmetal with an inconsistent mixture of ingredients so some warped with environmental temperature and humidity changes but many did not. Any attempt to straighten yours will likely result in breakage as decomposed potmetal is very fragile and brittle. Early potmetal was the dross skimmed off the top from refining other metals. I would try to buy the CNC code from Dan Arney and make a few more. A word of caution is possibly in order here though. The original part was a casting and the design included a compound radius inside the picture frame. To accurately duplicate the appearance of the original part by machine you would have to have CNC 5-axis simultaneous capability. Dan's reproduction bezels were run on a 3-axis machining center and while pretty close to the original they do not feature the original part's compound radius in the picture frame inside corners. If you need a bezel they sure beat not having one though and Dan should be recognized for stepping up and making parts available and filling a genuine need.

Paint can be whatever you want it to be but for best appearance results the gray should be a flat gray and the silkscreened nomenclature should be an aged or antique white. You really don't want bright refrigerator white silkscreening on these but that is what most silkscreeners will put on if you don't specify.  

Three of the knobs you need are specific to the SX-88 which are the Band Selector, Response, and Band Width. You could use the SX-42 (or HT-32) Band Selector knob and ignore the nomenclature since it will not match your receiver. The Response and Band Width knobs could be made from  a standard AF/ RF gain knob with a 0-10 skirt with painting and renumbering. All others were used on other Halli models.

It looks like you have the dial pointers fixed already but all they are is brass rods soldered to each side of a brass disc. If the epoxy does not hold you can always solder them later.

Be sure to support the phone jack with a wire tie to the Response control shaft, the leads are solid core and will break away easily moving the chassis around. Not a big deal but saves unnecessary additional work.

This is a receiver that will require extensive recapping if top results are to be realized and you really don't want to disassemble it a second time to revisit things missed during the first attempt. In my experience besides all the plate and screen bypass caps (which are the most critical) you have silver mica tank caps inside each of the 1550/ 2075KC first IF transformers which if left unattended to will likely result in a steady barrage of static crashes and sizzling bacon sounds in the audio. You will also find lots of resistors have drifted far over the high end tolerance range that will need to be replaced. In my estimation an SX-88 receiver will not be ready for alignment unless you have replaced all capacitors in the 1st and 2nd RF stages and 2nd converter deck in addition to all 50KC IF stages and checked and replaced all resistors as necessary.

It is very common to find broken lugs on 50KC IF transformers T-12 and T-13 mounted on the left rear corner of the chassis. Due to the triangular shape of the side brace the chassis will easily roll over and fall before you can catch it when out of the cabinet and stood up on its side. I always remove the side braces anyway and often screw one or both back on backward to use them as temporary chassis stands. If you remove the nuts the IF can will slip off with the coil form left in place but be careful about the clip on top, you don't want to tear the thin bakelite coil form while pulling on the can. You will have to unsolder the lugs anyway to properly recap so you might as well remove the IF transformers anyway. The cans are made of .015 stamped aluminum and .015 aluminum sheet stock is readily available. I always disassemble all IF transformers to check for overheated windings anyway and this is a convenient time to repair any pulled lugs. Straighten the torn aluminum around the lug mounting hole and press flat. Cut a small square of .015 sheet aluminum, punch a hole for the rivet and epoxy to the inside of the can over the affected area, use a C-clamp. When cured I re-rivet the lug to the can but small hardware of the appropriate size would work just as well. Be very careful with those threaded ferrite slugs as they are irreplaceable. Make a proper adjusting tool according to the directions in the instruction manual and don't be tempted to use something that seems to fit. The ferrite on top of the slugs is very thin and will break if the slug is tight and the appropriate tool that fits correctly is not used.

If the previous owner had the 2nd converter sub-chassis off you should see evidence of removed wire leads, there are about 12 of them and access to some is very restricted. Without proper equipment it is difficult to achieve professional looking results removing and reinstalling them and many SX-88s out there right now look like they have obviously been apart.

Regards, Greg

Hey Greg, I just got home.....
Thank you kindly for you very detailed response. It is very much appreciated! I agree with your thoughts on restoration. What I have done so far is repair some items recognized after the front panel was removed.
Electrically the receiver is in good working condition. As the pictures show, some of the larger capacitors were already changed. Cosmetically, I was very lucky to locate a NOS replica bezel that came from a lot done by Dan Arney several years ago. Over the entire week, I reached out to many people regarding the bezel and drive belt. But I owe a great deal too: Gary Harmon Jr. What a nice gent! The guys here on the forum, I can't begin to thank everyone! He could hear my passion to get this jewel back looking fine! What I would like to do, at the time I receive the bezel, I would like to make a blue print or mold or whatever needed to be able to make a replica. I am not in this for the money, just to offer the information to anyone that may in the future need a replacement as I do. I also located someone who began the project of getting the drive belt copied. He has the all the measurements needed and a company that was able to actually produce it. The price to produce was quite high, so I may need to investigate another manufacturer once the information is provided to me. Again, not for the money, I'm sure that many SX-88 owners would want an extra belt.

Thank you for your additional insight on how Dan's bezel were made.
Regarding T-12 and T-13, what I did was use JB KwiK to reattach the rivets on the left side.
I don't believe that the coils were broken, however, I may in the future completely remove them if I decide to
do a complete ground up restore. I think that the JB weld will remove if needed. Your process on the IF cans, should be one for the book. Please supply me with some pictures of the IF can repair if you have them. Can you supply me with a place to purchase the proper alignment tool for the IF can adjustment?

I don't believe that the sub-chassis has been restored. I need to remove the cover and take a peek inside. I don't have the proper soldering tools for wire removal. Don't worry Greg, I didn't tell you yet, but my SX-88 will be your 6th renovation! ;D

Greg, thank you so much for those pictures. I've seen some nice restoration work, however those SX-88 pictures are truly amazing! Something to be PROUD of!
I love the way you break it all down to the ground, clean, polish then re-build it all back up.
I am curious to ask if you have over 100 bench hours in the restoration shown?

What a beaut!
I'm sure #400 will be the same. I love the way the panels and metal boxes came out.
What do you use to treat the metal?
Is it a step by step process?

The front panel is going to be restored by Bob W0YVA in the near future. I'm on the hunt for an SX42 as well for the knobs.

Again, Thanks for everything!




Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on March 20, 2011, 10:03:40 PM
SX-88 Serial #400 currently in process:

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20400/SX88-40023.jpg

http://i104.photobucket.com/albums/m191/wa1kbq/SX%2088%20-%20400/SX88-40027.jpg

How about #203 after #400.
 ;D


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on March 21, 2011, 11:52:09 AM
http://www.wmberg.com/

http://www.sdp-si.com/press/New/Belts2_5.htm

https://sdp-si.com/eStore/Direct.asp?GroupID=213


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on April 17, 2011, 07:54:02 PM
First off I want to thank everyone who has offered assistance with the restoration of my SX-88 #203.
Soon, the front panel will be completed and sent back.
I haven't received the replica bezel yet, hopefully soon. I am still looking for the knobs...

However, I would like to share some thoughts, and am seeking advice on my next project.
Where and how to begin...It's dirty, some chassis rust, corrosion, etc....


I just acquired my second Hallicrafters SX-88.

I haven't received it yet!

This very rare bird is Prototype #2.

<snip> from original sale...

"Here is the rarest of the rare in SX-88's.  It is engineering prototype #2.  Chuck Dachis in the 2nd edition of his excellent "Radios By Hallicrafters" book describes his prototype of this receiver.  This one isn't quite as crude as his but has some of the same features.  The chassis is cold rolled steel with scribe marks marking some of the tube sockets.  It has the extra tube and i.f. can on the second converter sub-chassis.  There is no data plate on the rear panel and there are no holes drilled for one.  The "#2" is marked with orange crayon in several places on the chassis as you can see on the photos.  It looks like several people have gotten into this receiver at one time or another.  The original wiring is typical cotten covered wire as used by Hallicrafters.  The mods were later plastic covered wire.  Some of the wires are not hooked up, so the receiver is not operational.  All of the paper capacitors and some resistors have been replaced.  I have not attempted to plug it in as I don't know what would happen!  It came out of an estate in California several years ago.  I have not tried to clean it up as I didn't want to disturb the crayon markings.  The front panel is very good, but the original tuning knobs have been replaced by later Hallicrafters knobs.  All of the internal covers as well as the cabinet are missing.  Possibly other Hallicrafters cabinets might fit it.  It was rack mounted with some teletype gear when I got it. It has the original drive belt for the bandswitch, and the front bezel is not warped.  My less than perfect eyesight and shaking hands keeps me from trying to bring this great piece of history back to life.  I'll leave that to more capable hands than mine!  There doesn't seem to be anything missing other than the covers and cabinet."

<unsnip>

So,
Does anyone have experience with FILTH, DIRT, RUST etc....

Amazing that the front panel is in very nice shape, the original bezel is perfect, 99% original knobs, the drive belt is perfect....
I can easily part it out and cosmetically fully restore my other SX-88.
I don't want to do that.....

Some pictures to follow.....




Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on April 17, 2011, 07:55:51 PM
More pics....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on July 07, 2011, 11:08:37 AM
I just wanted to update everyone who had assisted me on my Hallicrafters SX-88 restoration.
Recently the front panel was sent to Bob W0YVA for a complete redo...
As many of you remember many parts including the front panel was anodized gold.
The front panel came back and it looks absolutely stunning!
Bob does beautiful work! I will be sending him the cabinet in the future for his magic!
A new radio friend sent me 2 original replacement dials, for the main and band spread knobs.
After many weeks of searching the entire country for a replacement bezel.
Only one replica bezel was found and immediately purchased. It just arrived yesterday.

I am still looking for the original knobs!

Pictures attached...




Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on July 07, 2011, 11:17:55 AM
Oh by the way,

I am not running to put this all back together yet. So if anybody would like to offer a computerized CNC milling machine and copy the bezel, let me know....


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on July 20, 2011, 06:25:14 AM
Oh by the way,

I am not running to put this all back together yet. So if anybody would like to offer a computerized CNC milling machine and copy the bezel, let me know....

  Any chance to buy a copy of the data ?


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on July 20, 2011, 08:31:47 AM
Tell you what...
There is a place not to far from me that uses CNC machines. I will go over there when I get the chance and ask them if they would consider making a program to cut the bezel. I will ask them for a price to do this, or will then even consider doing this type of job without making a prototype. Seems like the same situation with the drive belt.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on July 20, 2011, 08:35:31 AM
Oh by the way...
The replica bezel is a quarter of the weight of the original pot metal version. However the texture of the metal and how it was originally cut is quite different, I guess due to the composite makeup of the pot metal used in the 50's.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: kg8lb on July 20, 2011, 09:18:07 AM
 Len, Sorry, I thought you already had the data. There are plenty of shops in our area that could Rapid Prototype that part but the cost is a bit heavy in most cases. As for the hand lay up , there are also shops that specialize in applying textures to the mold. A good painter can usually duplicate just about any texture during the finishing of composite or metal parts.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WA1KBQ on July 28, 2011, 10:59:59 PM
Can you supply me with a place to purchase the proper alignment tool for the IF can adjustment?

I am curious to ask if you have over 100 bench hours in the restoration shown?

What do you use to treat the metal? Is it a step by step process?

The front panel is going to be restored by Bob W0YVA in the near future.


Len,

The alignment tool starts out as a General Cement part #8727. I need to order a couple new ones also and a quick check of the GC Electronics website shows they're still available for a little over $4 each and there is a link to a picture of the tool. The tip has to be reduced in size slightly to fit the small rectangular slot in the tops of SX-88 slugs. I use a small mill smooth file and work them down to the dimensions shown in the SX-88 manual. The slugs might break if they're tight, and often some are, if you attempt to use a screwdriver. The slugs are not available anywhere else that I am aware of.

I have not previously kept an account of time it takes to do a complete job but I did start keeping a record of that now on this latest job which is number 400. It has always been purely a labor of love and I just worked on them off and on mostly in my spare time (whatever that is) when I could find it. SX-88s are fairly complex receivers and it seems to take me quite a bit longer to go completely through one than other makes and models. The last two SX-88 projects took about a year each but that's not a fair assessment because I usually bounce around among four different projects in-process at any given time because it seems you are constantly getting temporarily held up on something, either looking for replacement parts or sending parts off for outside work, refinishing, plating, etc. I like to disassemble equipment as far as is practical, clean and restore each individual part as necessary and reassemble restored parts. A good restoration is simply an assembly of restored parts.

Improving the appearance of old tarnished and discolored cadmium plating can sometimes present a bit of a challenge and usually you don't want to employ more aggressive measures than necessary to restore a brighter appearance to the plating. Sometimes brightening up a dingy tarnished chassis will make quite a difference in a restoration but polished up like a mirror, while popular with some, does not look quite right to me. You should also carefully consider whether any polishing or cleaning to brighten the chassis appearance outweighs retaining the various original factory ink stamps and markings many of which will most likely be destroyed during the cleaning process. A very effective way to brighten tarnished cadmium is to dissolve a small amount of Sodium Bisulfate (pH Down for pools and spas) in a cup of warm water. With a shop towel and rubber gloves wipe the chassis down. If your cadmium is beyond achieving results with sodium bisulfate solution increase to slightly more aggressive phosphoric acid. This one is a green liquid available in quart size plastic bottles and auto body repair and paint supply houses sell it as a metal prep step before painting. Clean with a 50-50 mix of industrial 409 and ammonia to neutralize, rinse and blow dry. The 409 kitchen counter cleaner variety sold in grocery stores is not strong enough. A good substitute for industrial strength 409 is Westley's Bleche-Wite which is a tire cleaner sold in automotive parts and accessory stores. The sodium bisulfate solution is a weak acid and the cleaning step removes discoloration, improves the brightness and neutralizes the acid. I always wipe down a freshly cleaned chassis with a protective coat of Cimguard (or WD-40) afterwards to preserve the luster and retard oxidation.

I have seen some very good work from Bob, WYVA, glad to hear he is doing silkscreens. I need to call him.


Regards, Greg


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on September 25, 2013, 08:11:17 PM
So, Where am I now 2 years later?

I have been on the hunt for the original knobs...
I did find and purchased a donor (prototype) SX-88. But even before I received it, I sold it back to the gentleman I purchased it from. He was sad to let it go, and I understood why he purchased it in the first place, to restore and needed the cash at the time of sale.

So maybe 2 E-bay auctions since, and after bidding my limit, unable to win..

Tonight I finally received my 2nd SX-88.
Now this receiver was just purchased to be a donor radio. I simply needed the original knobs to complete mine and a cabinet repaint and done. But what I received, was a complete fully restorable SX-88.

I only unwrapped it about an hour ago. The gentleman I purchased it from did a fantastic job at packaging. Double boxing etc.. It was well worth the wait for the extra time and effort he took wrapping this 98 pound beast. It survived the UPS gorillas!

First quick inspection, reveals a broken band belt and broken window glass on the left side.
The always broken replaceable IF cans in the back left corner are untouched in excellent condition. Someone built a bracket in the left corner to prevent breakage as a preventative measure.

I cant believe that the front BEZEL is as straight as a arrow. The cabinet is straight and somewhat clean. The front panel is quite clean with only some fade on lettering on the panel switches. All the knobs are in great shape and will clean up nicely.

The top reveals slight surface rust, the bottom clean and somewhat untouched....The switches, band switch and controls all move freely.

Restore this one too, have two, (I really don't need 2) and back to looking for the knobs....
Do I take only the parts really needed and sell it minus the knobs...
Part it out to gents who really need the bezel, and cabinet, what pieces needed?
Take the best parts from the 2 and sell the balance?
Should I keep the original panel, sell the newly refurbished W0YVA uninstalled panel, use the original Bezel, sell the last NOS uninstalled reproduced new Bezel? (That took over a year to locate and secure)...

My gut feeling is to not destroy and fully restore this beauty!

Here are some pics...
Suggestions by my AM friends?
What should I do?

Thanks,
Len

 





Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on September 25, 2013, 08:14:55 PM
another pic..


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on September 25, 2013, 08:40:27 PM
Len,

I would say it is in very restorable condition and I would not part it out.  I know you have been looking for parts for awhile to restore #1 but it would be tough for me to steal parts from one that is in pretty good shape.  BUT it is yours so regardless of what the rest of us think it is your right to decide.

One SX-88 is enough for me although I do have a pair of National NC-400 and Pierson KP-81 receivers and having two would allow you to pair SX-88 receivers with your two favorite transmitters :)


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on September 25, 2013, 09:13:36 PM
Hey Rodger,
Thanks for the reply..
I appreciate it.
And, I too am leaning towards the restoration way....

I am going to take a closer look this weekend.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on September 28, 2013, 05:48:58 PM
Rodger,

I began the dismantle of the front panel. Question...
What type of tool is used to remove the knobs?
Is it bristol or spline? What size?

It looks like a 4 leaf clover.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on September 28, 2013, 06:29:32 PM
Len,

That is known as a Bristol with four flutes and some of the sizes have four flutes instead of the more common 6. In the Xcelite set I own the correct tool is # 99-63,  I believe 99 is the tool set identifier and 63 is the actual tool.  I think Cooper bought Xcelite.

The set I bought years ago is identical to the one currently sold on Amazon.  Use this for reference as you may find it cheaper elsewhere.  I guess you could buy the individual tool but it is a good Bristol set if you don't already have a complete set:  http://www.amazon.com/Xcelite-Compact-Bristol-Multiple-Spline-Screwdriver/dp/B001T4VXH0


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on September 28, 2013, 08:56:25 PM
Thanks for the information and link. I will order a set as I could definitely use them.

I was able to slide out the broken band belt. So, I reopened the belt project again. I made several phone calls to companies that produce timing belts. Looking to see if a belt close in size would be available. 112 groves, 1/8" in width etc...
Will see if I receive any replies.

I want to first remove the front panel and inspect the gear drive.
So I will first ofer the wrench set to get moving.

Strange, the Sx-101 knobs look almost the same in size and pattern. Different mounting screws than the 4 flute pattern.

Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WQ9E on September 28, 2013, 10:31:19 PM
If you find a source for a workable belt please let me know.  Mine is OK now but a spare would sure be nice to have.


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: Joe Connor on September 29, 2013, 01:00:23 PM
This is a fascinating thread. Keep it coming!

              Joe Connor


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on November 21, 2013, 08:23:22 PM
Well after about a month and a half, the Xcelite Spline Tool case finally arrived....
I waited for a used set to appear on the bay then grabbed a very old set when they became available.
Wow, Did that make it super easy to remove these knobs....

Thanks Rodger!...
Removal of the front panel and bezel next....

Happy Holidays....
Len


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: KD6VXI on November 21, 2013, 08:38:32 PM
Not sure if they are still in business,  but PRB (Projector / Recorder Belt)  is / was a great place to get belts.

One of my favorite mail order houses when I was an Authorized Alpine Service Center.   

--Shane
KD6VXI


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on August 14, 2015, 10:47:39 PM
If you find a source for a workable belt please let me know.  Mine is OK now but a spare would sure be nice to have.

Hello Rodger,
Two years later I was lucky to find a Spare NOS Reproduction SX-88 Band Drive Belt from 1996.
Also included in the sale was (2) Pairs of Reproduction Dial Glasses.

I hope to finally complete (after 4 Years) this SX-88 restoration soon!

Regards,
Len N2LEN


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: WBear2GCR on August 15, 2015, 10:57:23 PM
Len,

Great perseverance!

Hope you actually listen to the radio and use it after all this painstaking work and time!! Wow.

How about some pix of the unit as it now sits??

                          _-_-bear


Title: Re: Hallicrafters SX-88 Restoration Advice....
Post by: n2len on August 16, 2015, 08:12:16 PM
Len,

Great perseverance!

Hope you actually listen to the radio and use it after all this painstaking work and time!! Wow.

How about some pix of the unit as it now sits??

                          _-_-bear

Hey Bear,
Hope you are doing well and thanks!

Yup...
I almost gave up on this project. The receiver was put aside for quite sometime.
It really was a cosmetic basket case!
All that really needs to be done is to put the front panel all back together.
I will take many pictures and gladly share them as soon as I get it back on my workbench.

Len





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