1911 frame fixture prototype

[KY DAN]

I want to build a fixture to all me to re cut rails that are re welded and to be be able to cut a 31.5 degree feed ramp with out the need to constantly re indicate. And I want to do it without spending money lol

Planning on using 1 inch 1045 plate and surface grinding each face and squaring the edges via mill.

The slide release hole from the top of rails is located .450 inches down and I intend to use that as a datum from which the hammer pin hole is located 2.973 inches to the right and .016 inches higher at .434 inches. This accomplishes having the rails mechanical square.

The frame will pivot on Slide release hole and the feed ramp angle pin will be located .6128 from top of fixture and 1.000 to right of datum hole. In my minds eye the pin will rest on top of the slide rail and clamps can be used to fashion Fram to fixture.

Please let me know what your thoughts are regarding the hole locations and angles.

 

[KY DAN]

This is my solution for indicating a frame for 31.5 degrees using dro on milling machine and a test indicator

 

[Bronco72]

Would like to see a picture when you make the prototype !

 

[Blue68f100]

I'm assuming your going to clamp the Al plate to 2x4x6 block or something similar? You really want to be able to cut top and both sides without touching your setup. The commercial plates have a degree marking to set the receiver in at angle. Different mfg and calibers have the angle changing. So you may need some adjustablity.

When you clamp the receiver use a mag well filler block. This way you will not distort/damage the receiver. I use my end mill to cut the rails when I'm fitting a new slide/receiver. I tilt my head if I need to cut the ramp. Then I have to reset my tram which does not take very long since I have the tool to do it.

 

[KY DAN]

I'm assuming your going to clamp the Al plate to 2x4x6 block or something similar? You really want to be able to cut top and both sides without touching your setup. The commercial plates have a degree marking to set the receiver in at angle. Different mfg and calibers have the angle changing. So you may need some adjustablity.

When you clamp the receiver use a mag well filler block. This way you will not distort/damage the receiver. I use my end mill to cut the rails when I'm fitting a new slide/receiver. I tilt my head if I need to cut the ramp. Then I have to reset my tram which does not take very long since I have the tool to do it.

My plan was to make the fixture tall enough to have clearance to rotate the frame and clamp onto it with my Kurt vice. I need 2 inches for the vice to hold, I am using 1 inch because I think it should have the rigidness required in order to stand unsupported.

I am going to remove material once the fixture is made to access both sides of rails. I am dealing with one problem at a time lol.

 

[Blue68f100]

As long as you don't get too wild with your feeds the Al will/may work but it's not as rigid as I would like. If your working on a SS receiver I would want a more solid hold. Carbide mills don't play well with chatter. I've machined parts with them extended above the vice a couple of inches and you get vibrations, unless you take lighter cuts. Needs all the upper support you can give it for rigidity.

I use a 2x4x6 block to hold my receiver, very solid using steel, only the rails are above the block. With the Al 3.5" above the vice it's going to have some movement, chatter. I would use a 90deg plane to bolt it too. With the diag support to make it solid.