Is there a difference between the finish on the frame of a Model 39-2 and a Model 6904? The slides are steel and blued, are the alloys of the frames different, are the finishes different? I think the 39-2's are anodized, how about the 6904?

Thanks.

The 6904, 3914, 3904, and other of the same genre are more of a matte black - I believe some of the earlier 3904 had the high gloss of the 39 and 39-2.

Virtually all aluminum frames are anodized to prevent oxidation and provide a wear resistant hard surface. The degree of polish of the frame will affect the degree of gloss of the final finish, all other factors being equal. The specific alloy isn't going to change the appearance of the finish.

I believe the 3 & 4 digit guns used a powder blast matte finish for the frames before anodizing. This would cause a less reflective finish which was becoming seen as an advantage.

same process however?

Here is the reason why I asked the question...I had a Model 39-2 and the finish on the frame was pretty chipped and scratched, my gunsmith cooked it in his ultrasonic/hydrosonic cleaner with the heat on, it lifted most of the anodization off the frame, he then polished off the rest, with the result being a pretty trick looking two-tone 39-2. I just picked up a 6904 with a frame in the same condition, so he tried the same process - and after 3 days of cooking the finish has not budged. This is why I was wondering if the process was different between the two pistols. Now he is thinking he will have to glass bead the frame on the 6904 before polishing.

My wife's 3914 was bead blasted before being hard chromed and that took the anodizing right off. I also had a 6906 refinished years ago and that one was also bead blasted before re-anodizing the frame and it came out looking like new.

There are finishes that achieve a molecular bond with the base metal, Armoloy being one. Not knowing the exact process being used by S&W on their later pistols, I can't definitively answer. I'm not sure if those finishes are considered anodizing, a goodly portion of the processes are propriety secrets.

However, if that's the type of finish applied to your pistol, the only way to remove it would be either a mechanical removal or an electro stripping process. Ultra sonic cleaners aren't going to budge it.

I did have a customers abused 39 refinished in Armoloy and it came back looking like stainless. They use a very fine flour blast as pre-plate prep for Armoloy.