Refinish Prep of Colt Autos - Methods, etc ?

rhmc24

This is an estate building thing rather than buy and sell. I have about 15 units in various stages of original, completed, awaiting and as-is.

I collect beaters and parts and build 1902 and 1905 Colt autos. This concerns the flat sides of slides and frames. Most have fallen on hard times and some badly pitted. My poor man's surface grinder does a good job of getting a flat clean 120 finish. Haven't been able to find finer discs. I get mirror finishes by succession of finer wet or dry, then 3M polishing paper. I use a wood paddle backup to try to keep flat and sharp edges. I don't buff. I outsource re-lettering.

I'm not satisfied with the edges - not as sharp as they should be. Wondering what I am missing equipment-materials wise or in method.

Any info, opinions or comment will be appreciated, here or my GB profile.
Thanks,

Spartacus

use a piece of 1/4" or thicker glass as your backing and spend more time with finer grits rather than coarse and fast.

asphalt cowboy

I use pretty much the same method you do, sans the surface grinder.
I use a 1/4"x1"x4" steel coupon instead of wood though. I wrap a strip of 1" wide wet dry paper around it length wise and wet the metal with mineral spirits to float the slurry.

Since you're working with something shorter than an octagon barrel it may work to grind a sheet of plate 12"x12" and apply lapping compound to the plate and press the slide to that. Make sure to use the entire surface of the plate to avoid uneven wear patterns.

rhmc24

I guess I should explain further. After I get the slide ground flat to remove old lettering & pitting with 120 grit, I go in steps of about 220, to 600 with wet or dry, then 800 to 1200 using flat stones or diamond panels. After 1200 I use the 3M polishing paper in its several steps--on up to 4000.

The paper I wrap around a small wood block. With each grade of abrasive I do a pattern about 30 degrees across the surface until none of the previous marking can be seen, then another pattern the other angle to remove all the previous, then again in line with the panel. Then I change to the next finer, repeating the same process until I get the mirror polish.

A harder back up has to be an improvement. I will put it to use on another 1905 starting in a few days. The flat plate idea sets me thinking - maybe try it on my drill press table as a quick and dirty trial.


This is the 'poor man's surface grinder" I run in my drill press.

Thanks for reading and responding.

zink

Draw file them then polish. You can re-do it to factory specks depending on the polish. Colt slides tended to be a higher gloss on the sides of the slide with a duller appearing on the top. When polishing always use backing, just using fingers (known as the devils fingers) causes rounding.

Lance

Bill DeShivs

The flap wheel is probably the culprit rounding your edges.
As said, draw file, and sand after. Tape the paper to a very flat surface, and draw the slide across it.
Or, use a belt grinder with a flat platen.

rhmc24

The surface is quite flat after the surface work for most of the procedure, not from the surface grind which I control carefully. Working down with flat stones and diamond panels. It seems to occur during the higher polishing, giving dull edges rather than sharp -- in the sense of a dull blade rather than sharp. Only you people who are knowledgeable and critical would really know the difference.

I'm thinking that the polishing papers being drawn across the edges probably carry debris that affects the edges. Next one I will minimize the cross strokes, use a hard backup lengthwise a la drawfile.

Thanks for your thought-provoking comments.