Here are some links, through which you can download the schematics of some useful gunsmith tools, for those who like to tinker with their 1911. The files are in Autocad .dwg format and .jpg image format.
The slide lug measuring fixture is used to measure the distance from the breech face to the back of the slide lugs where the barrel lugs make contact. The surface opposite the holes on the main body is placed squarely on the breech face and the stepped portion at the top of the slide piece is allowed to make positive contact with the slide lug. Once it is in contact with the lug, tighten the set screw, remove the fixture and measure from the piece that touched the breech face to the step on the slide piece. You might even want to put a little pressure on the slide piece with your finger while tightening the set screw. It works best if the pistol slide is held upside down in a vise. This fixture is large enough to measure all three slide lug to breech face distances. Be sure to measure each lug more than once to make sure your measurements are repeating. For best results, the measuring surfaces should be surface ground. If no surface grinder is availabe, careful milling will produce very good results.
The sear jig is used to adjust and stone the primary angle on the sear nose. The sear angle can be adjusted with an 8-32 screw that is screwed into the tapped hole in the bottom of the jig. The secondary angle is stoned by placing a .020 inch feeler gauge on the top of the stone with the sear feet in contact with the feeler gauge while the nose is being rubbed back and forth on the stone. This narrows the sear nose and produces an approximate 45 degree secondary angle.
The plunger tube staking tool is used to stake the feet of the plunger tube into the frame. The staking pin is pressed into the body of the tool and fits into the conical holes in the plunger tube feet. The slot of the anvil is placed over the plunger tube and a 5/16-18 X 1 inch long socket head cap screw is screwed into the tapped hole and tightened down against the anvil. The end of the screw needs to be flattened in a lathe for best results. To keep from crushing the plunger tube, place a #42 drill bit in the small hole and either a #36 or even better a 7/64 drill bit (if it will fit, it depends on the size of the hole) in the large hole.
These files were provided by our Forums Site member, 3jaw.
Plunger tube staking tool (.dwg)
Plunger tube staking tool (.jpg)