Sliding on in.

Next up on my 1911-ish project is fitting the slide.  I machined the rails just a tiny bit oversized to leave room for hand fitting so that I could get the best possible fit between my frame and slide.  When I went to start fitting it though, I noticed something odd.  My frame rails were bent.  You can see the slight wave in the left rail here:

Weird, right?  Here's what I think happened.  When I clamped the frame in the vice for the last CNC op, the rails were facing down.  I can see witness marks from the vice showing where it was.  Here's where I had it clamped in the vice: 

I didn't think anything of it because there was solid aluminum in front of and behind the magwell and the vice wasn't actually touching the rails, so I really cranked down on it.  All I can figure is that the vice compressed the aluminum, but because there was no support at the magwell those areas just bent instead of squishing.  I'm not super concerned because it shouldn't really affect strength and some frames omit that portion of the rail entirely.

Anyway, fitting a slide is easy, but tedious.  File, check, file, check, repeat until it fits.  Instead of Dykem or some other layout fluid to see where the frame is making contact, I just use a black Sharpie.  Any spots that end up shiny get material removed.  You'll want to go slow and check frequently because it's easy to overcut and hard to fix if you do.  It probably only took me an hour or so to get my slide fitted and functioning right.  To my surprise the barrel needed virtually no fitting at all, just adding a very slight chamfer to the VIS area of the frame(which I'd purposely left out when I machined it).