Dechroming!

[findwolfhard]

Hi!
I tried to get the chrome of a Leica top by using an NaH bath and and galvanic set up using a car battery charger. I had to stop process because it worked partially right through the chrome and copper into the brass!
So I`m stuck now!
Any advice or better sent it to England rightaway for the intended job, namely repainting in black.
Any advice would be very much appreciated!
best regards Wolfhard

 

[splitimageview]

Hmmm. How many locations were affected? How long was it in the solution?

 

[findwolfhard]

Hmmm. How many locations were affected? How long was it in the solution?

Hi ! Nothing really serious! I stopped before real damage could be done! What is left ca be easily filled out by varnish and or filler! But I do not know how to go on. I live in Germany and all specialised workshops (surface treatment) do not accept private orders, bmiraculously some are located near Wetzlar and work for Leica!!!
Best regards Wolfhard

 

[bsdunek]

Did you check out these threads? http://www.rangefinderforum.com/forums/showthread.php?t=36032
http://www.rangefinderforum.com/forums/showthread.php?t=4239

Several people successfully de-chromed their top and bottom plates with no ill effects.
One thing is to keep the current down. If the solution is bubbling and boiling, it's too much. Secondly, the parts should be turned often. This keeps the de-chroming more even.

Generally, the base metal is copper plated first to provide a good support, then nickel plated for the color, and then chrome plated for the luster. Going through the copper won't hurt, but making depressions in the base metal, brass or steel, is bad.

I don't recommend using acid, although some are successful with it.