Zinc Plating for parts restoration

[Lostinidaho]

I like old odd rifles. Due to budgetary constraints I can't afford the museum pieces. And maybe I would want them if I could afford them. Many old odd rifles, mostly just parts in a box find me.

Not that I want "new out of the box condition" but many have parts that are extremely pitted.

I was wondering if you could use zinc electroplating as a pit filler on the non-pressure parts e.g. butt plates, trigger guards etc.

A friend had some old motorcycle parts Zinc plated. The plating really smoothed out the surface without any sanding or polishing. That got me thinking.

So this is the process I was thinking....

1. Derusting-- I like evaporust

2. Zinc plating

3. Sanding to remove back to the steel of the high spots

4. Repeat 2 & 3 till pits are filled

5. Cold rust bluing if that is the correct finish

6. Black Patina the Zinc.

Thoughts, tell me if I am crazy.

Thanks in advance

[GregLaROCHE]

If you are are considering getting into zinc electroplating and all that is involved, you should check out rust removal using electrolysis. Basically you put parts in a solution, add electric current and the rust (iron oxide) is removed and deposited on an anode supplying the current. Much more efficient than de-rust products.

If you plate parts with zinc and sand down to a smooth finish, I doubt if most bluing finishes will give you a uniform finish, because the chemicals won’t react the same with the zinc as the steel. Some people use paints on guns these days and that could work, but then why not fill with an epoxy.

I have a favorite gun that unfortunately, got some rust pitting on the receiver while it was stored for ten years. I explored different ways to repair it, but couldn’t find anything short of micro welding to repair the damage. I opted to just leave it the way it was.

[Lostinidaho]

I have done eletro-chemical rust on large antique car parts. It has worked well. On car parts I always had to go and dig out rust from deeper pits to get it really clean of rust. Evapo-rust just seems to get to the bottom of pits in an over night soak.

I do think there would be a difference in color, but it could only been seen in the right angle of light.

[bangerjim]

So..............in other words you would be satisfied with the Zn coating found on standard sheet metal today? That is hot dipped, but the EP finish would be very similar.

Zn is subject to darkening and corrosion from acids, even those in you skin. Not like Cr or Ni plating found on most firearms. You could possibly fill divots with several coats and significant sanding/filing down. That process in it self can yield lots of work for a very poor resultant surface finish. Zn is very soft compared to Cr or Ni.

But that Zn plating process may yield the result you wish. Try it and let us know.

banger

[waksupi]

Dye Acraglass black, fill holes and sand down, then finish.

Just a guess, but I would give it a shot.

[Lostinidaho]

I have found epoxy based compounds usually will bridge over many pits. Then sanding with sand through the bridge.

I thought zinc would work for several reasons
1) fills pitting--can be built up to .5mm or possibly more
2) softer than steel so it can be readily sanded with out
3) can be undone without damaging original parts
4) parts can be masked so some areas of parts will be plated and other areas will not be plated

[GregLaROCHE]

The color of the bare metals will be similar, but if you use chemical bluing, I think the colors will be different between the original metal and the zinc. Has anyone ever tried cold or hot bluing on zinc? What are the results ? Maybe you could leave an entire polished zinc coating on the entire gun.

[abunaitoo]

I've always wanted to try zinc plating.
I was thinking of using zinc wheel weights cast into bars.
Would the wheel weights work?????

[john.k]

Hot blueing would dissolve zinc,in seconds.....cold blueing,and I use them loosely ,probably does nothing ,same as on steel.

[bangerjim]

The color of the bare metals will be similar, but if you use chemical bluing, I think the colors will be different between the original metal and the zinc. Has anyone ever tried cold or hot bluing on zinc? What are the results ? Maybe you could leave an entire polished zinc coating on the entire gun.

Most times Zn will come off on your hands like Pb does. After handling a bunch of sheet metal (hot-dipped with Zn) one time, I found that out fast. And as I said, the acids in your sweat and skin will turn it dark and gray. I certainly would entertain other ideas that plating a gun with Zn! The items you may have around the home that are cast from Zn are generally electroplated with gold, silver, chrome, nickel, or other metals that will not degrade like Zn does.

[LAGS]

I would Opt for the Epoxy filling first.
If it doesn't work out the way you want , then it can be easily removed with Heat.
But it might limit you to Cold Bluing your parts.
Which should work out on non collector model type guns

[samari46]

Don't recall the name but there is a product that very closely resembles the black oxide finish that used to be on Williams and Armstrong hand wrenches. I believe it's a two part process. Have seen it mentioned for firearm finishes when one doesn't want to spring for a blue job.Frank

[bangerjim]

Many tool makers use nitriding as a black rust preventative finish. Very durable but is done in a vacuum oven with disassociated ammonia gas! Not for you home shop handyman! I used to sell a line of gas analyzers that the aerospace industry used to do nitride coating gas analysis.

Several years ago I perfected an electro-chemical process to create dead flat black finishes on antiques. It is possible for a person to produce that finish easily with the right chemicals (proprietary!) and process.