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AMfone's Online AM Handbook => Restoration => Topic started by: VE3LYX on December 15, 2012, 01:03:47 PM



Title: Broken vintage unobtainable voltmeter housing repair
Post by: VE3LYX on December 15, 2012, 01:03:47 PM
Bakelite meter housing repair.
I received a WW2 military radio bench supply. Max 300 volts according to the badly damaged meter for volts. The outer ring was missing but the glass was there. Just on a whim I tried something I have used in make carb parts in my other life. I cleaned and waxed the other meter and the metal panel behind it or the chassis. I smeared it first lightly then later heavily with RTV silicon (Automotive) After letting it dry for a couple of days I removed the silicon from the good meter carefully. I opened a couple of air holes in the top of my new mold right over where the missing parts would be.  I mixed up some JB weld and put in enuf to replace the missing bakelite parts of the meter. I waxed the metal behind this too although I think a piece of paper would have been a better idea. I then placed the mold with the JB weld over the remaining pieces of the broken meter. Since it is exactly as the the other milliampmeter other then scale readings it fit perfectly over the remaining pieces. I pressed it tight and flat along the panel as well letting the extra ooze from the holes I made for this purpose in the face of the mold. I left it for two days and then removed it. I am not skilled at this type of thing as some of you are  but I was surprised at the result. An almost perfect repair of a hopelessly damaged and unobtainable meter. I made sure the glass was in its proper place as well before pressing the mold home.  I was a bit shy of having enuf JB weld in the mold so I have a few minor repairs to make but they are doable. A bit of sanding some careful painting (black) and I will have my missing meter back. Perfect? No but almost. If you have nothing to lose and need to restore a part at least till you can find one or a matching pair it is a very workable idea. It sure beats looking at half a meter. All I had was the lower half. The ringed flange around the glass was completley missing  having been broken away. Now it is complete.  
Don VE3LYX  


Title: Re: Broken vintage unobtainable voltmeter housing repair
Post by: KL7OF on December 15, 2012, 07:19:56 PM
What a great idea and a nice save on the meter.....I'd like to see a picture...Does JB weld have metallic composition?  Thanks..Steve


Title: Re: Broken vintage unobtainable voltmeter housing repair
Post by: KA0HCP on December 15, 2012, 07:22:14 PM
thanks for the ideas!


Title: Re: Broken vintage unobtainable voltmeter housing repair
Post by: K7LYF on December 15, 2012, 11:34:34 PM
QUOTE: "What a great idea and a nice save on the meter.....I'd like to see a picture...Does JB weld have metallic composition?  Thanks..Steve"

Yes, JB Weld is metallic. It is used on all sorts of cast iron and steel repairs.


Title: Re: Broken vintage unobtainable voltmeter housing repair
Post by: VE3LYX on December 17, 2012, 10:09:10 AM
Save. Right word for the proceedure.
That is true. JB weld has a metalic component. I should apologise for that as I am by trade a mechanic and was making or refining manifold for my race car (The Senior Dragster) and it was sitting there on the bench so I used it. Any epoxy based deal or similar would work. I am kicking myself I did not take a photo when I started. I didnt really think it would work I guess. The result surprised me. I will post a pic when I get it done. Like I said I am not gifted craft wise. Others of you who have that extra skill would be able to get a near perfect result the first time. Now I wish I had repainted the scale and straightened the needle and painted it as well. The neat thing on this power supply was not so much it still works but it actully had the original patch cable clipped to itself around the handle. I kept the mold and may try to pour a front flange in porable epoxy just for fun today.
Don VE3LYx


Title: Re: Broken vintage unobtainable voltmeter housing repair
Post by: Ed/KB1HYS on December 17, 2012, 09:30:14 PM
Nice Save!!  That was a great idea with the mold, and almost the same method as an investment casting, minus the molten metal  ;D .

I bet after paint it will be completely indistinguishable from the original meter!

That JB weld is great stuff.  I patched an engine block on a four cylinder with it where the head gasket had burnt through between the two middle cylinders..  I ran that car another 20k before it died.  Makes a difference when you're broke.

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