Thread: Mars copper contact plates - can you replate them?

I have 2 Mars bars, an Aurora Borealius and an Oscillating Spectrasystem. My issue is the copper contact plates for the positive connection is rubbed through in a couple of spots. So when the light head goes over that part it either goes out or dims. Is there a way or a place what will replate these things? Any suggestions is welcomed! I'm not trying to make these things perfect (not yet at least), but I want them to be fully functional and this is driving me crazy.




Thanks
Rich "RJ"

Since it looks to be a simple copper plate bolted/screwed in place, I would take the measurements of thses plates or take to whole thing to a professional metal shop and ask them to reproduce the plates. Might not be the cheapest to have them custom made but I don't see why it wouldn't work.

The thing is these are not solid copper, they have a backing on them to keep the positive of these and the negative of the chassis of the light from mixing. I guess I could get new ones made and just bolt them on top of these.

Originally Posted by toon80

Since it looks to be a simple copper plate bolted/screwed in place, I would take the measurements of thses plates or take to whole thing to a professional metal shop and ask them to reproduce the plates. Might not be the cheapest to have them custom made but I don't see why it wouldn't work.

Fabricate new plates. You can trace the old plates on to the new copper sheet and cut them out. Make a new insulating material for the back and install a fuse on the line that feeds power to the plates.

Also see if there is a shop near by that does metal plating.

It's a circuit board. Bloody simple. You can get a thin, but rigid copper plate that's remounted on top of the existing board or on a new circle that's not conductive like a thin piece of lexan / plexiglass from Home Depot or the like.

But wouldn't you still ground out the replacement plate by screwing it down? You'd also need to find a non-conductive material to use as a washer where the nut/bolt secure the copper plate. Right?

^^^^^^

Originally Posted by EVModules

...remounted on top of the existing board or on a new circle that's not conductive like a thin piece of lexan / plexiglass...

Originally Posted by EVModules

It's a circuit board. Bloody simple. You can get a thin, but rigid copper plate that's remounted on top of the existing board or on a new circle that's not conductive like a thin piece of lexan / plexiglass from Home Depot or the like.

Or stop at Radio Shack or a ham supply place and pick up some pieces of blank circuit board stock and cut it to shape. There might even be the etching kits available, too if there is a need. Be sure to get the stuff that is fairly thick and has copper plating on it. The newer types of plating will wear away fast.

If this is a temporary repair:
1) Remove the screws
2) Rotate the plate 180*
3) Reattach plate

That should work on the strips as well as the round contact plates, although you may have to drill new holes for the strips. As I recall, the screws are insulated by a sleeve. Should keep the lights shining brightly until you decide to restore.

Originally Posted by pc0k894

But wouldn't you still ground out the replacement plate by screwing it down? You'd also need to find a non-conductive material to use as a washer where the nut/bolt secure the copper plate. Right?

Good point. Looking at the pictures, it appears that the issue is addressed somewhat when I don't see evidence of insulation between the copper and the screw.

Thanks for all the suggestions. I found a few places to get single sided copper circuit boards. I think I'll go that route and try my hand at clean cutting the board. As far as insulation and grounding the screw holes in the base are 2x larger than the screw. They are also recessed and have rubber grommets to keep the screw from contacting the grounded base. I'll take pictures of what it looks like I the next few days.

Originally Posted by EVModules

Good point. Looking at the pictures, it appears that the issue is addressed somewhat when I don't see evidence of insulation between the copper and the screw.

Personally, I have always used thin brass sheeting and cut it to shape using the originals as templates. The attaching screws have insulating sleeves already on them so just install the new plates on top of the originals. Simple, effective, low cost and easy to do. Best of all, it will outlast the original copper.
John Dorgan
P.S. You can't replate the originals as the plating won't adhere over the fiberglass backing.

Thank you John. I think I'm going to leave the original plates intact and just put brass over top. I'll update the post with pictures of progress after cleaning up this Aurora. It was the one on ebay the other week. It's amazing how well it works now that all the dried up grease has been removed and fresh oil has been put on everything.

I've cleaned the years of caked up grease and grim off her. The base is kind of odd, it's non ferrous, and pretty heavy. It's rough on purpose. I thought I might sand it down and get it chromed, but that would ruin it's authenticity. It came out pretty good. I polished the dome with a mother's polishing ball and plastic polish. I oiled it up and cleaned up the copper contact plates as best I could. One day I will go through the process of replacing the plates completely. The other Mars bar I have, the Oscillating Spectrabar that I have could use a new set of plates as well.







Here's the other Mars bars I have
Plain rotating Spectrasystem 1/2 bar, 4 sealed beams



Here's the other Mars Oscillation 1/2 bar, 4 oscillating sealed beams


Also, I had to look up the patent for the Aurora Borealius:
Patent US3309661 - SIGNAL DEVICE - Google Patents
Thanks everyone for your ideas on how to fix the copper plates.
Rich "RJ"

Looks like and early-run AB. Very unique with the different base finish.

Originally Posted by CrownVic97

Looks like and early-run AB. Very unique with the different base finish.

I too have the same finish on my old Mars RB.

I've replaced several contact plates, in fact the two A.B. I own now along with my nephews have all had new plates installed simply to 'save' the originals. As others have stated just get a sheet of blank PCB, I cut the long one on a foot shear and use a circle cutter in a drill press for the round ones. I have the tools but if you don't you can go to any tin-knocker shop and they will cut you a set for a few bucks. Another trick to extend the life of your A.B. plates is to use NO-OX-ID A-Special, just follow the directions.

RJ,

Very nice cleanup and I wouldn't take it any further--she looks good and you've retained the authenticity. Nice score!

Marc

On a related note, I about fell off my chair yesterday when I saw the A.B. on ebay actually sold for the two-grand reserve.... yikes! I have only paid more than $1k once for one, and I only did so because it came with spares including motor, gearbox, and dome. The one in the auction sure looked nice in the pix/video but wowzers that's a lotta clams, I like the hunt, and sure I may be cheap, but that just seems like a crazy price to pay when better deals can be found. Either way hope they enjoy and it ends up as the cherry on top of a nice restoration.

Originally Posted by AuroraBorealis

RJ,

Very nice cleanup and I wouldn't take it any further--she looks good and you've retained the authenticity. Nice score!

Marc

Agreed, leave it alone. I love the almost 'Art Deco' style of the plate on the early A.B.s, I have still yet to find an early one myself which why I have found so many of the newer ones, I keep searching hoping to uncover one but get stuck with another new model.

Originally Posted by Aerobat

Agreed, leave it alone. I love the almost 'Art Deco' style of the plate on the early A.B.s, I have still yet to find an early one myself which why I have found so many of the newer ones, I keep searching hoping to uncover one but get stuck with another new model.

Same here. That light looks beautiful just as it is.