Curiousity, Silver capped contacts.

[adam mizer]

I was curious about these silver capped contacts on copper.
Looking around to digest the copper I saw an example with: Ascorbic acid, Salt, Hydrogen Peroxide.
So I tried this mix.
There was initial reaction and mind you the Hydrogen Peroxide was added in small increments, I noticed a strong reaction.
So for a few hours I kept adding the H.P.
After I was sort of fed up because I saw a lot of copper and reaction was so slow I added a couple doses of Hydrochloric acid to maintain a reaction.
Very slow reaction and subsided to nothing.
Very disappointing with this type of contact, probably the last time I will try.

So.... this has my interest heightened with the waste now.
I have a green solution with a light blue salt.
Thinking the green is probably copper and having trouble coming up with an answer for the light blue salt.
Wondering if someone else has seen this?

 

[adam mizer]

Here is another batch but difference was contact is attached to a steel base.
Same setup as above but mostly steel base.
I take it that the brown color is the steel possibly.
While rinsing I notice that what appears to be micro copper particles washing off.
Also a tiny bit of that light blue is seen.

 

[Yggdrasil]

I was curious about these silver capped contacts on copper.
Looking around to digest the copper I saw an example with: Ascorbic acid, Salt, Hydrogen Peroxide.
So I tried this mix.
There was initial reaction and mind you the Hydrogen Peroxide was added in small increments, I noticed a strong reaction.
So for a few hours I kept adding the H.P.
After I was sort of fed up because I saw a lot of copper and reaction was so slow I added a couple doses of Hydrochloric acid to maintain a reaction.
Very slow reaction and subsided to nothing.
Very disappointing with this type of contact, probably the last time I will try.

So.... this has my interest heightened with the waste now.
I have a green solution with a light blue salt.
Thinking the green is probably copper and having trouble coming up with an answer for the light blue salt.
Wondering if someone else has seen this?

Why in the world would you use Ascorbic acid (Vitamin C) to dissolve anything?
Have you studied the links you were given when you arrived here?
Silver will react with Hydrogen Peroxide (as a catalyst) by decomposing it.
As the Salts, hard to say.

 

[Yggdrasil]

Here is another batch but difference was contact is attached to a steel base.
Same setup as above but mostly steel base.
I take it that the brown color is the steel possibly.
While rinsing I notice that what appears to be micro copper particles washing off.
Also a tiny bit of that light blue is seen.

The reddish brown is Copper.

 

[anarxi]

I was curious about these silver capped contacts on copper.
Looking around to digest the copper I saw an example with: Ascorbic acid, Salt, Hydrogen Peroxide.
So I tried this mix.
There was initial reaction and mind you the Hydrogen Peroxide was added in small increments, I noticed a strong reaction.
So for a few hours I kept adding the H.P.
After I was sort of fed up because I saw a lot of copper and reaction was so slow I added a couple doses of Hydrochloric acid to maintain a reaction.
Very slow reaction and subsided to nothing.
Very disappointing with this type of contact, probably the last time I will try.

So.... this has my interest heightened with the waste now.
I have a green solution with a light blue salt.
Thinking the green is probably copper and having trouble coming up with an answer for the light blue salt.
Wondering if someone else has seen this?

Hello.
Yes, you can poison copper with ascorbic acid ¿¿!
I haven’t read or heard of that.
Citric acid + peroxide + salt are used.
30 grams + 100 milliliters 3% + 5 grams.
in these proportions this solution dissolves 3 grams of copper

 

[anarxi]

with the following contacts, silver on copper.
There are three main ways:

complete dissolution in nitric acid, this also applies to iron holders, the silver will dissolve and then throw away the iron.

dissolving the copper base in a solution of water and salt + nitric acid.
the silver will be covered with chloride and then either washed in ammonia or immediately melted.

desoldering of silver parts using electric welding made from a microwave oven.
other options are not economically viable...

The citric acid method works well on thin holders such as in relays

 

[adam mizer]

Thanks for the reaction to the post.
These are just tests to see what happens.
The solution colors differ.
Both tests done at the same time and with the same additives.

Why is one green and the other brown?
In the Green beaker there was silver contact over copper only.
In the brown beaker there was much more with silver over steel base. Also appears copper is dropping/plating out on other metals.
Also what is the light blue?

 

[Yggdrasil]

Thanks for the reaction to the post.
These are just tests to see what happens.
The solution colors differ.
Both tests done at the same time and with the same additives.

Why is one green and the other brown?
In the Green beaker there was silver contact over copper only.
In the brown beaker there was much more with silver over steel base. Also appears copper is dropping/plating out on other metals.
Also what is the light blue?

Please confirm exactly which acid you used!
Did you really use Vitamin C powder, Hydrogen Peroxide and Salt?

 

[anarxi]

If you put iron and copper into the solution at the same time, the copper will dissolve and at the same time restore the irsilverone count.
In addition, in modern “silver on copper” contacts, not pure silver is often used, but an alloy of silver and nickel (90/10).
what makes silver magnetic.
There may be other compositions.
and they just dissolved from the top layer of silver...

 

[adam mizer]

Ascorbic as labeled. Kosher Sea Salt, Hydrogen Peroxide.
Ratio of Citric 60grams, salt 30 grams, peroxide 12% small additions for several hours.
Lastly when fed up I added Hydrochloric acid 200ml to each, no change. But there was some reaction.
Today I am cleaning it up and checking it.
Both beakers same time equal volumes.
(Also cleaning up my gold foils from AP) right now.
I'll get a closer look in a while at the silver contacts, I'm interested why copper appears on silver surfaces.

 

[Yggdrasil]

Ascorbic as labeled. Kosher Sea Salt, Hydrogen Peroxide.
Ratio of Citric 60grams, salt 30 grams, peroxide 12% small additions for several hours.
Lastly when fed up I added Hydrochloric acid 200ml to each, no change. But there was some reaction.
Today I am cleaning it up and checking it.
Both beakers same time equal volumes.
(Also cleaning up my gold foils from AP) right now.
I'll get a closer look in a while at the silver contacts, I'm interested why copper appears on silver surfaces.

Ascorbic acid is Vitamin C and used to precipitate Gold from Solution.
Citric acid is a mild acid used to clean rust from steel and such.
Why do you not use HCl?

 

[adam mizer]

Here are pics of the Brown liquid contacts.
These are full silver contacts and many are on steel base, thats why magnetic. The silver is not magnetic.
One pic closeup I cleaned the silver contact and made a scratch in the soft silver.
Other pic dirty contacts and then slightly cleaned silver, you can see the steel mounts bars better.

 

[adam mizer]

There's my mistake then. I thought Ascorbic and citric were the same stuff????
Thank you. Me dummy some/many times.
I have my torch and removed many contacts and these ones were so small to grab on to and I thought they would be easy enough to remove base metals.
So I should use HCL Peroxide (AP)? for copper. And HCL for steel?

 

[adam mizer]

Waste from the green liquid drops copper like in this bucket.
Waste from the brown liquid drops black in this beaker.

 

[anarxi]

Here are pics of the Brown liquid contacts.
These are full silver contacts and many are on steel base, thats why magnetic. The silver is not magnetic.
One pic closeup I cleaned the silver contact and made a scratch in the soft silver.
Other pic dirty contacts and then slightly cleaned silver, you can see the steel mounts bars better.

what a wonderful work mess

from the point of view of engineering logic, mounting pure silver on iron is somehow absurd...
looks are deceiving...
understand that this is pure silver, you can either fuse the contact, or make a shot with an xfr pistol,
or through wet analysis.
weighing of raw materials - dissolution - recovery of silver - weighing...

 

[Yggdrasil]

There's my mistake then. I thought Ascorbic and citric were the same stuff????
Thank you. Me dummy some/many times.
I have my torch and removed many contacts and these ones were so small to grab on to and I thought they would be easy enough to remove base metals.
So I should use HCL Peroxide (AP)? for copper. And HCL for steel?

You surprise me, you have been here since 2015 and have not studied enough to get the need for precision in the chemistry.
Have you read Hokes book at all?

Anyway it is common practice to use the tested and proven ways until you master them before you start experimenting with unknown procedures.
AP (Copper Chloride etch) is recommended for thin layers of Copper, but use air bubbling in stead of Peroxide.
HCl are fine for steel.

 

[anarxi]

There's my mistake then. I thought Ascorbic and citric were the same stuff????
Thank you. Me dummy some/many times.
I have my torch and removed many contacts and these ones were so small to grab on to and I thought they would be easy enough to remove base metals.
So I should use HCL Peroxide (AP)? for copper. And HCL for steel?

There's my mistake then. I thought Ascorbic and citric were the same stuff????
Thank you. Me dummy some/many times.
I have my torch and removed many contacts and these ones were so small to grab on to and I thought they would be easy enough to remove base metals.
So I should use HCL Peroxide (AP)? for copper. And HCL for steel?

easier to dissolve in dilute nitric acid.
The contacts dissolve, there is no base

 

[adam mizer]

You surprise me, you have been here since 2015 and have not studied enough to get the need for precision in the chemistry.
Have you read Hokes book at all?

Anyway it is common practice to use the tested and proven ways until you master them before you start experimenting with unknown procedures.
AP (Copper Chloride etch) is recommended for thin layers of Copper, but use air bubbling in stead of Peroxide.
HCl are fine for steel.

Yes, I stopped doing this stuff 10 years ago.
Some things I'm trying and get myself confused like ascorbic and citric, however it did work a little. Some base metals almost completely removed.
Yes I read a lot of Hoke over 10years ago and need a reread.
Back then it was fingers, karat and filled gold. Sulfuric cell. Converters. Sterling and solid contacts.
I'm changing my methods, now I inquart gold with silver. Which I never understood.
Also these little relay contacts, I want to learn to remove base metals which I never knew how to do really.
Its like starting over again.
So far my gold is looking great.
Silver have a lot to learn.
Also looking into removing IC's from ram boards roughly 100 pounds of boards.

However this is about removing base metals from small relay silver contacts.
Its time to reread Hoke.

 

[adam mizer]

what a wonderful work mess

from the point of view of engineering logic, mounting pure silver on iron is somehow absurd...
looks are deceiving...
understand that this is pure silver, you can either fuse the contact, or make a shot with an xfr pistol,
or through wet analysis.
weighing of raw materials - dissolution - recovery of silver - weighing...

I'm sorry did I say pure silver? Thats not so.
Maybe my meaning of full silver contacts was not appropriate.
The body of the silver button contact is full not capped.
Full of what ever alloy used. Most likely low percentage.
There are some contacts mounted on iron or steel and I would guess by the appearance before I start was thinking looked like spot welded on.
I just removed one now, cut it off.
And yes its magnetic. Some alloy with steel or as you suggested nickel its soft and cuts sort of easily with a wire stripper.

 

[adam mizer]

Most are these magnetic ones.
Now I will separate the non magnetic pieces.