It was a dark and stormy night and I wasn't looking forward to the metal finishing of a trigger guard. However, I decided to make a clamping jig that would ease the effort a little bit. The objective was to make a system similar to the one described in Peter Alexander's
The Gunsmith of Grenville County but, one that could be used to do both sides of the trigger guard
I sketched out some ideas and started with making two machinist parallel clamps. Note the 5/16 round bar attached with 1/8 inch spring/roll pin. The clamps are probably a little more complex than need be, notice ball bearing in the end of the tensioning screw you can probably get along without that. Clamps are made from 7/16 12l14 square bar about 3 inches long. Screws are all 1/4-20 x 1 1/4 inch.
I built a two piece L brackets to hold the clamps out of cutoff material I had on hand. Not the simplest way to build the bracket but, it was what I had to work with. The are 5 x 3 1/2 with the long leg made of 1 x 1 and the 3 1/2 leg of 3/4 square 6061.
Clamps attached to the trigger guard.
Attach the trigger guard and clamps to the L brackets, with a set screw on each side, adjusting the width by sliding one of the L brackets on the 12 x 1/2 inch round bar as required. All set screws are 1/4-20 x 1/2 inch.
The jig works very well and is solid with no movement. I believe the nice part of this design it the ability to flip the guard, with clamps attached, and be able to finish both sides. Just two set screws in the basic jig to loosen and flip the guard. Of course the whole jig can be tilted, reversed in the vise etc. The basic L bracket is to complicated (two piece) and could easily be simplified based on other material. I suspect the parallel clamps are commercially available in an appropriate size and could be modified with the addition of pins. Thanks for getting this far.
