03-24-2018, 08:00 PM
bj139 Wrote:I think I will try my next one with a router with the jig I have. It appears similar to the EP Armory jig.
I may have to buy a trim router. Thanks for the idea.
Use plenty of transmission fluid for cutting fluid - I use a squirt bottle. Don't try to go to full depth in one pass - cut it in stages but make sure that the smooth shank of the router bit is always set to ride against the jig or you've just destroyed your jig. I start out with one 5/16" hole drilled down on a drill press nearly into the trigger slot, place my ΒΌ" router bit into that hole and then start it up with a firm grip on the router so that it doesn't move when it starts, and make that hole bigger in easy cuts. Router bits cut best on the sides, not so much in plunge mode. I clear the chips often and I use a combination square to check my depth of cut every time I clear chips. Taking too aggressive of a cut with those cheap routers can let the bit slip in the collet and the cut will get gradually deeper - so check that depth. Save the last .010" for a final pass to get a nice cut in the bottom (which matters zero to the rifle's functioning). Take your time (~3 hours or more) and you can produce a nice looking lower. Then go take a shower and change those oily clothes.
My jig didn't fit my blanks that well and I had to drive the alignment pin into the jig some so that it would close on the receiver like it's supposed to. Tape in contact spots can keep the jig from wearing through the oxide, but these days I don't worry about it and just touch up afterwards with Aluminum Black.