Hello DSK & everyone, we’re really opening up a can of worms when talking about different types of stainless steels, metallurgy, hardness and galling because there are hundreds of different types formulated for different applications. When you add or subtract certain elements such as chromium, nickel and carbon you compromise another quality. I’m not sure of the exact alloying elements or lack of that attributes to the galling, I’d have to look it up but in our gunsmithing work it’s really a moot point because we are stuck with what we have to work with.
Yes stainless steel does have a bad reputation for galling and machining. Smearing of the steel is a good description as noted above when tolerances are to tight when rubbed together with friction. For example if the slide and frame are fit to tight the parts may gall and bind. If a few thousandths of clearance is left galling should not be a problem.
I have read on this forum that some smith can fit slides & frames snug and lap them smooth with good results. I think this is a gamble. I seen one nice stainless slide to frame tightened in the traditional squeeze & peen method and lapped so smooth if felt like it was running on KY. I’d a bet a weeks pay it would never gall.
It was lubed with a generous amount of some sort of non-galling super lube formulated for stainless steel. It ran for about a 100 rounds and seized-up so tight it had to be beat apart with a mallet.
Now keep in mind all slide and frame sets are not created equal. They differ from manufacturer to manufacturer and even from the same manufacturer. Heat-treats vary from lot to lot. So bottom line is since it worked on this set don’t necessarily mean it’s going to work on the next set.
I have experimented with welding grossly sloppy slide to frame fits on stainless frames by using 4130 welding wire to build-up the frame rails and re-machine. This will put a hard layer of about .005 on the sides of the frame rail. I fit them-up fairly snug and everything seemed to workout fine for a 100 round test fire. I’m going to have to run it a few thousand before I have complete confidence in the method, I’ll let you know if I run into trouble.
Some grades of stainless are very difficult to machine. Some types like the 400 series used in gun making are free machining, which means the steel cuts very nice and yields a nice finish. 400 series is also magnetic and heat-treatable. Some other grades seem to tear and smear rather than cut freely.
Steel hardness is sometimes a little confusing when speaking of machine ability. With all things being equal the harder steel will be more difficult to machine, but there are softer metals like some grades of stainless and titanium’s that are way more difficult to machine than a harder grade of free machining steel.
Below is a previous post were I ramble on about steel in general that may shed more light on the subject if you have not yet read them. "Why your stainless rust"
Stainless steels also hold the heat very well and it takes more BTU’s to get them hot.
On the other extreme aluminum will heat-up faster than any other metal and also cool down faster. A good example of this is my crab steamers used for steaming seafood. On the same burner the stainless pot will take longer to bring-up to a boil and start producing steam than the aluminum pot. The aluminum pot will heat-up faster and boil but also sheds its heat faster.
If I were to build the ultimate 1911 it would be in blued steel not stainless and industrial hard chromed.
But on the other hand I also really like the Colt stainless. It machines and polishes beautifully. One day I’m going to build me one so I have one of each.
Pay your money and take your pick, Metal Smith
[This message has been edited by Metal Smith (edited 06-11-2001).]