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THE AM BULLETIN BOARD => Technical Forum => Topic started by: K2GTM on March 31, 2022, 05:01:03 PM



Title: Hammarlund SP-600 Front Panel Refinishing
Post by: K2GTM on March 31, 2022, 05:01:03 PM
Hello all,

I have a Hammarlund SP-600JX-17 that needs to have it's front panel repainted.  Does anyone know of someone who can do this?

Thanks and 73,
Greg K2GTM


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: AB3L on April 01, 2022, 11:11:23 AM
W3HM had the silk screens for the front panel. I had mine done years ago. Although, I don't know if he is still in business at this point.


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: K2GTM on April 05, 2022, 09:20:16 AM
Thanks, but I think Mr. Mills is no longer taking new work.


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: WBear2GCR on April 05, 2022, 12:38:27 PM
Engraved or screened?

If it is engraved, then the process is not very difficult...
- strip paint, usually a chemical stripper will do the job.
(the "newer" strippers are "citrus" based, some work better than others - DO NOT get ANY on your
skin!!) If the citrus strippers fail, find an old MEK based, work outside and wear a respirator...
- residual paint in the engraved parts can be removed with either more stripper or a blaster using
baking soda media.

Assuming no scratches/gouges, then a very light coat of primer.
IF the panel is aluminum, use self-etching primer.

Permit to dry thoroughly. Heat is important, and time.
You want time to let the paint really flatten.
Then put on the color coat.
A light 1200 or 2400 grit before the color coat is a good idea.

Be sure to use paint that is compatible with the primer!!

The only issue is that you do not want to fill the engraving with color paint.

After that, and it is fully dry, you can use lacquer stick or some types of acrylic
hobby paint to fill the engraving. Again that 2400 or finer paint, followed by some
rubbing compound, then polishing compound will bring it up nicely and get rid of
excess from the engraving fill.

Check with Chuck, K1TLI, he specializes in Johnson, but he might do an SP-600.

Anyhow that is how I do up panels, SP-600, R-390 and the like...


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: WBear2GCR on April 05, 2022, 12:41:16 PM
It only allowed me two pix...

This was an overpainted TMC power supply... can't even see the engraving with the old paint!!
Had to go with the more toxic MEK based stripper, the citrus did not touch this paint.

The last one was pressure blasted... took the paint and the engraved stuff, the stripper left the
white engraving behind on an R-390a panel!


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: W3GMS on April 05, 2022, 04:16:57 PM
Not sure where the rumor started that Howard was not in business, but the last time I talked to him which was maybe 4 or 5 months ago he was still in business and going strong!

Joe-W3GMS


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: Opcom on April 09, 2022, 01:22:44 AM
MEK Someone gave me almost a gallon of it. Nasty, and nasty-smelling stuff but cleans everything. We used it at Sony to clean betacam video heads and drums. Customer would leave a machine on pause and go home. Next day tape residue was cooked on.


Title: Re: Hammarlund SP-600 Front Panel Refinishing
Post by: K2GTM on April 12, 2022, 04:22:42 PM
Thanks for the tips, Bear!  My panel is engraved and I had planned on filling-in the lettering myself.  I had my brother (who does body work) paint the panel, and it looks great, but he ended up putting on way too much paint.  (I told him not to, but I think he was just used to doing it his "usual" way.)  I wish I could just pick out the paint from the lettering, but I don't want to mess anything up.

I'm tempted to try and paint it myself, but I have plenty of other things to do and this is one of the few radios I want to look nice.
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