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View Full Version : Polishing stainless steel yourself from matt to blindingly shiney :)


shiroikuma
March 28, 2001, 04:59 PM
Is it doable? I did a search and found some confusing replies about doing this. I as because I have a Kahr P9 which has a matt stainless grey slide (bead blasted maybe) and I would love to have a mirror finish on it, without chroming the slide. If it would take more than a couple of hours and $20 bucks or so it would be a treat.

Someone in an old thread said something about watching out for rust if you polish it shiney. I don't understand why this would be more of a problem with a shine as opposed to matt finish.

I was thinking about using either a dremel (which I have) and rougue, or maybe starting with really fine sandpaper but I don't know where to find stuff more fine than 600 grit. I tried some Flitz metal polish but I'd be very old before that did the trick.

Any help?

shiro

E. BeauBeaux
March 28, 2001, 05:13 PM
If you just have to do something, the finish is not smooth, and will first have to be made so. Go with a med grade emery cloth then go to fine. Finish with crocas cloth, after all this jewelers rouge and a dremel felt buffing wheel should do the trick. If you did a good job with the hand rubbing use the white rouge. This will take alot of time but very little money. But, what's time when it's a labor of love.

John Forsyth
March 28, 2001, 05:21 PM
I have a stainless Kimber that had the matte finish. I also wanted a shiney slide. Here's what I did.

Get some sand paper and emory paper. Local hardware store, auto parts store or Wally World. You will need a grit starting at about 250, then 400, 600, 800, and 1000.

Get a piece of glass. I got one about one foot square and 1/4 inch thick. This is so you can tape the sand paper down to it.

Tape the 250 paper to the glass. Place it on a flat supported surface. Work the slide back and forth on the paper. Not round and round. Then move to the next finer paper and repeat. When you get through with the 1000 grit paper, you should have a mirror finish, almost.

Here's what my Kimber looks like now. Good luck.

http://albums.photopoint.com/j/View?u=160512&a=1172784&p=39087171&Sequence=0&res=high

JNewell
March 28, 2001, 09:16 PM
Stay the heck away from the Dremel. It is too small, and most of them are too fast. Polishing metal, especially with motor-driven tools, is an art, and one that takes quite a lot of instruction and experience.

Mr. Forsyth's idea is very clever. The suggestion of the glass would keep flat surfaces flat and keep the engraved/roll-marked markings from washing out. Of course, it's more suited to Ol' Slabsides than to, say, a J-frame. :-) I've seen paper as high as 1600 in autobody stores. If you get that far, then you could work with rouge or polishes like Simichrome that have rouge in them.

It will be hard to restore the finish once you start, so it would probably be a good idea to practice on something whose cosmetics you don't attach a lot of importance to.

UK2TX
March 28, 2001, 10:30 PM
Shiroikuma,

The reference to rust is a concern when the passivation of the stainless steel is removed by working the material ( in this case polishing ).
In lay terms, the passivation process removes "free iron" contamination left behind on the surface of the stainless steel from machining and fabricating. These contaminants are potential corrosion sites that result in premature corrosion and ultimately result in deterioration of the component if not removed. In addition, the passivation process facilitates the formation of a thin, transparent oxide film that protects the stainless steel from selective oxidation (corrosion). Working the material will remove this and expose a "fresh" surface "full" of free iron, this surface is prone to rusting, remember it's stainLESS not stainfree!.

Baths of nitric acid concentration in the 20 to 50% by volume range are generally specified as the solution to passify stainless steel.

Regards,

UK2TX

Corrected the "rushing" to "rusting"

[Edited by UK2TX on 03-29-2001 at 11:11 AM]

Romulus
March 28, 2001, 11:10 PM
UK2TX, is there any "hydrogen embrittlement thing" when passivating (?) SS with nitric acid? (the latter is a great wart remover, as it reacts with proteins, but I digress...)I am a little confused about hydrogen embrittlement, which the literature warns us about, and the fact that so much metal treatment, such as described in your disquisition, relies on the action of acids. I am worried about even derusting my guns with naval jelly, the "phosphoric acid thing," you know...

BTW, if your moniker means what I think it means, the culture shock did not interfere with your lucidity, I am happy to note...

UK2TX
March 29, 2001, 12:01 PM
Romulus,

Thank you for the kind words, you are correct in your assumption.

As for the embrittlement, other than knowing that it dependent on the hardness of the material ( above Rockwell C30 ), I have no idea as I'm a computer geek not a metallurgist.

I would highly recommend visiting http:\\finishing.com if you have unanswered questions as the metallurgist and chemists on their board are highly knowledgeable ( and friendly too ).

UK2TX

shiroikuma
March 29, 2001, 12:41 PM
thanks for all the replies. I like your kimber John F. It looks nice, though I wish the picture was a little more clear. I think that is what I would like to do on the Kahr, polish the sides and leave the top mattt to reduce glare.

shiro

Romulus
March 29, 2001, 04:20 PM
Shiro, good luck with the polish job. I agreewith JNewell's view on dremel polishing. I've seen pictures of the definition taken out of a beautiful Winchester lever-action receiver with that method...

UK2TX, thanks for the link.