What "grit" reproduces S&W brushed stainless finish?

[SLT223]

I have a 66-2 and I'm debating cleaning it up a bit after years of carry duty. It's really not that bad, but I would like to learn how to restore the finish of an older SS S&W.

Is there a certain "grit" # and/or technique to making the gun look new without making it shinier? As always, I appreciate your insight.

 

[varmint243]

I read somewhere on the internet (probably on here) that it's an acid etching of some kind.
I would like to know more about how that is done as well.

 

[hittman77]

Burgundy or gray Scotch-Brite pads. We get 'em at O'Reilly's or Auto Zone around here.

 

[flintsghost]

The original finish is the result of an acid dip at the completion of the manufacturing process. It not only leaves a dull matte type cast to the stainless, it is also responsible for making it slightly more rust resistant. If it is cleaned up or polished, bead blasted etc, that additional level of rust resistance is gone.

 

[SLT223]

Thank you for info on the original process. Is there a manual way of recreating it?

 

[George_in_SD]

wet dry 1000 and 1500 grit
brass bristle brush
scotchbrite pads (The green ones under the sink you're thinking about have too much bite in them for me)

Go slow, go with the grain, use light pressure.

 

[wantmoresmiths]

I just ran across this following thread yesterday. Hopefully skjos shares his info and pictures soon.

http://smith-wessonforum.com/smith-...7421-glass-bead-media-testing-5906-frame.html

 

[Kernel Crittenden]

Bead blasting, and a brushed or satin finish, are two different things. A M66-2 would of had a brushed finish. As already mentioned, gray 3M synthetic wool gets pretty close.

Passivization is the process used to put a thin chromium oxide film on stainless. It forms naturally over time. You couldn't stop it if you wanted too. But, if you want to do it quick, like S&W does, you can bath your parts in a solution of white vinegar mixed 50/50 with hot tap water. An hour should do it.

A similar process is used in the food industry with SS pipes and equipment. They usually will do the mild acid bath over night, then flush with clean water in the morning. They do it to better protect the SS from harsh cleaning chemicals, which they want to begin using almost immediately, so they can't afford to wait for it to passivate naturally.

 

[DWalt]

After bead blasting or any abrasive use on a SS surface, acid passivation should be performed. A Citric acid solution dip is the usual treatment. It removes any free iron from the surface, and thereby improves corrosion resistance. Citric acid is not very hazardous (many food products contain it) and most supermarkets carry it in the form of Lemi-Shine (powder), used in kitchen dishwashers to prevent glassware spotting.