Clever Fixturing For an 80% 1911

Thanks to Wirecutter at  Knuckledraggin' My Life Away, we find a link to a new way of making a 1911 from an 80% frame without a milling machine.  Designed at Stealth Arms, the new fixture, called a Phantom Jig, guides your cutting of the necessary features by hand.  The operations required to complete their version of the 80% frame are to drill a couple of holes, cut the slide rails and the barrel seat.  The Phantom Jig performs the cutting operations that would usually be done on a milling machine.

The jig with a frame in place - when you buy the jig, they include one frame.  Note the long black handle: in operation, you use this like a woodworking plane.  The cutter is lowered into cutting position by the black knob with finger grooves located next to the handle, and the handle is then used to push the cutter forward through the metal taking off - ? - "several thousandths".  The rest of the jig needs to be held in a sturdy vise to handle the forces you're going to generate on it.  Once you make a cut, you advance the cutter 1/10 of a turn of that knob and cut another pass through the frame.

Wirecutter embeds this video, but I didn't watch all of.  It's 45 minutes long - and the video author said it took 40 minutes to finish his frame.  Stealth Arms has a video on the Phantom jig's page showing how this all works. 

I post this because I like clever, and this approach just exudes clever.  If you have even a table top drill press, you can drill the two holes you need to drill.  (Seriously - get a drill press if you don't have one.)  Then all you need is this fixture, a bench vise, an hour, and some good old fashioned elbow grease.  I think I should warn that this fixture isn't going to get you there if you're trying to complete a steel frame.  I think that requires more shear force than you can generate.  Stealth Arms' frames are made of 7000 series aluminum, which is heat treated to a higher hardness than the more-common 6061-T6 "aircraft aluminum".  7075, for example, is used in high-end mountain bikes.

Making a 1911 is pretty high on my list of projects right now, and I'm keeping an eye out for a steel frame.  Since I have a milling machine, and making one without the jig is cheaper, chances are that's the way I'll go.