# REMOVE TIN PLATING



## danieldavies (May 30, 2013)

hello! how do i remove tin plating from copper? i have tried using hydrchloric acid, the plating dissolves off but plates straight back on.


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## Geo (May 30, 2013)

what type of copper are you trying to remove the tin from? the tin will not just "plate" back to the copper. try to use more volume and dilute the hcl with water 50/50. warming the solution to speed up the process.


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## goldsilverpro (May 30, 2013)

danieldavies said:


> hello! how do i remove tin plating from copper? i have tried using hydrchloric acid, the plating dissolves off but plates straight back on.



The plating books all say to use full strength hydrochloric acid, which is usually about 37%. Muriatic acid is only about 31.45% and it may or may not work. 

An old standard is a solution of 120g/l sodium hydroxide (NaOH) at room temperature. When you dissolve the NaOH in water, the solution will get hot. Let it cool before using. Wear a full face shield and gloves when dissolving it - it might splatter. Make the part the anode, use a steel or stainless sheet for the cathode, and run it at 6V.

You might try soaking in white vinegar. I've used it for tin on steel. It's slow.

Whatever you try, clean the parts first.


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## Lou (May 30, 2013)

Caustic soda works really well. Know a guy who does a 100K lbs a week of tinned bronze that way.


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## 9kuuby9 (May 30, 2013)

goldsilverpro said:


> danieldavies said:
> 
> 
> > hello! how do i remove tin plating from copper? i have tried using hydrchloric acid, the plating dissolves off but plates straight back on.
> ...



is it really necessary to run a current trough the object in order for it to work as you described?

Let's say I have small bits coated with tin, and I wanted to remove that; how would it work out with this method without using electrical current?

Cheers,

Ben


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## Lino1406 (May 30, 2013)

Unfortunately "tin plating" contains Lead.
To remove them strong HBF4 is needed,
possibly with H2O2
Lino1406, author "30 recovery procedures..."


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## danieldavies (May 31, 2013)

the tin plated copper is from fiber CPUs (the heat spread on the back).


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