View Full Version : Motorola VT-71 restoration advice needed


Mars777
07-31-2012, 11:30 PM
Hi all:

I am in the process of chassis cleaning of the copper coating. I never cleaned a copper coated chassis before. Though I am having success in using Brasso.
There are 2 concerns that I have before I go any further:
1) How thin is the coating on the TS-4J chassis and is there any danger of it being rubbed off?
2) I haven't cleaned any area as of yet that has printing. Will Brasso take off the printing? Please look at the picture to see what I mean.

TIA!
Tom

mstaton
07-31-2012, 11:37 PM
The plating is thin but should be OK as long as you don't go overboard polishing. I would use a q-tip and just go around the lettering as best you can, I would not take a chance.

bandersen
07-31-2012, 11:51 PM
Hi Tom. I suggest staying away from the printing too. Having polished up one of these chassis once myself, I'm not sure it's worth all the time and effort. It will tarnish again if not protected.

Mars777
08-01-2012, 12:47 PM
Thanks Guys;

I will use Q-tips around the lettering.

As far as polishing goes, well it is too late for that. I already started. So for protecting it after polishing, do you guys recommend clear coating it? If so, what product type do you recommend for copper? Clear lacquer, acrylic, etc. I recently got a tub of Simichrome Polish. It says it adds a "protective layer". Will this suffice in lieu of clear coating?

A couple of years ago I clear coated a Hallicrafters S-40 chassis after stripping off the awful looking cadmium coating. It still looks like new!

Tom

Winky Dink
08-02-2012, 03:03 AM
I do what I can to save the model number and other chassis stamps, but sometimes the factory graffiti is unavoidably or accidentally obliterated. If you don't mind cheating, here's a way to restore the original appearance:

https://picasaweb.google.com/coldrb/ChassisStampReproduction?authuser=0&feat=directlink

Brasso makes a more convenient product for delicate work. They sell a can of Brasso-impregnated soft cotton. I've only seen this on military bases, but it's great for small areas.

- Winky

Phil Nelson
08-02-2012, 01:05 PM
They sell a can of Brasso-impregnated soft cotton.Perhaps you're thinking of Nevr-Dull. I found it in a store somewhere around here. Also for sale online, of course.

http://www.nevrdull.com/

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Einar72
08-02-2012, 02:05 PM
Brasso wadding polish seems to be only available from the UK:

http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=wadding+polish

Mars777
08-02-2012, 11:05 PM
Hey Guys:

I was starting to run out of the old Brasso that I had, so I tried the new stuff. It stinks! Totally useless compared to the old.

So I said to myself; "There's got a be a better method". I did some searching on the internet and found people had great results using vinegar and table salt. So I used some of my wife's generic household "White Vinegar". I poured a little bit in a low glass and threw in some table salt. Then I threw it in the microwave to dissolve the salt. I applied it to the copper coated chassis and let it stand for 30 seconds. No rubbing, just wiped it off. Amazing! Did a better job than the old Brasso did!

I also purposely, got some of the solution onto the flat black painted surface in the electrolytic section to see if that did any damage to the paint. I plan on repainting that area anyways. It didn't touch it!

So this is my next plan:
Next to the Ballast tube there is writing there. I want to try this on this area and make a video of it so that you can all see how this experiment works. I am thinking here that the vinegar solution will not disturb the writing there. It is painted lettering. If it does, it's not the end of the world anyway. I figure if this works I'll then use it for the important writing on the back where all the controls are.

To give you an example of this, look at the picture below. Notice that in the center is where I did use Brasso, which took around a half an hour. Now look around the whole periphery. I did this whole are with the vinegar and table salt in the same or even less amount of time and NO rubbing! The cost of the stuff is what, 1-3 cents? Little cheaper than Brasso and doesn't effect the paint!

snelson903
08-03-2012, 12:46 AM
it will turn out ok , you should see the condition of this zenith chasse iv had to deal with reminds me of rusted out car body ,but im getting through it better than giving up and junking it.

Reece
08-03-2012, 02:53 PM
The acid and salt method does clean, BUT it is very corrosive. You need to wash it down thoroughly to get the last traces of it off. The stuff gets into wherever there are "pores" in the copper plating down to the steel chassis and rusts it. In the first wash have some baking soda to neutralize the acid of the vinegar. Then use plain water. I made a copper plated chassis rust badly by trying to shine the copper with salt and lemon, which works great on things like Revere Ware, which of course you can wash thoroughly when done.

Mars777
08-03-2012, 03:09 PM
Whoa... Thanks Reece!

I hadn't thought of neutralizing it. Yeah Baking Soda would be perfect to use.

I thought of the salt aspect of it though. I know underneath it is a steel chassis, but the upper and underside are both copper plated. Does this mean that I am pretty safe to use the salt if I thoroughly neutralize it then wash it?

Thanks for the tips!

Tom

Kevin Kuehn
08-03-2012, 10:49 PM
Of course that plating was originally used because of its natural oxidation process protecting the bare steel from a much more rapid deterioration. This was all about a cheap mass production method to prevent the steel from rusting. However these plating's were never intended to be a long term decorative finish. I'm not saying it's a bad thing to polish one up, I'm just not too keen on it being an historically accurate process. Probably the only person to have ever see that chassis so shinny, was the factory worker that pulled it from the plating tank. :scratch2:

compucat
08-05-2012, 10:53 AM
I tried polishing the chassis on my 9VT1 with disappointing results. I ended up painting it a color that was a fairly close match. Now when I take the back off of my set for service it looks almost like new inside.


http://www.videokarma.org/showthread.php?t=253313

Phil Nelson
08-05-2012, 02:41 PM
I'm not saying it's a bad thing to polish one up, I'm just not too keen on it being an historically accurate process. Probably the only person to have ever see that chassis so shinny, was the factory worker that pulled it from the plating tank. :scratch2:Correct. These were appliances made on assembly lines. The factories did not employ squadrons of elves with polishing rags. I have polished a few chassis in my day, but only because it seemed fun at the time and I had nothing better to do.

We have a house full of antique radios & TVs, and I have never, ever pulled the back cover off a set to show someone a shiny chassis.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Mars777
08-05-2012, 11:33 PM
Hi Phil:

"squadrons of elves with polishing rags"

I love that statement! :D

The only reason that I'm doing it is because bandersontv did it with one of his TS-4J chassis and it looked great!

Well, I'll just have to finish the job now, clear coat it, and then show you guys how it came out. Wish me luck!

Thanks much,
Tom