AK Receiver Flat Bending Jig

thingiverse

# AK Receiver Flat Bending Jig/Die ## REV 1.8 ### Print Settings Up the temps ~10 degrees and increase your extrusion so the layers bond well together. ** 8 perimeters ** If you print this thing with 2 outside perimeters it will probably crumble. Print everything but the press standing on end. Suggest you use a raft for the flat bar. ### Materials needed - ~.6kg PLA filament - 4x 5/32" pins (https://www.amazon.com/gp/product/B082ZNJ1DH/ cut one of these in 4. Not required but helps with alignment) - 7x 1.5" 1/4x20 bolts - 7x 1/4x20 nuts - 5/32" drill bit (not required if not using the pins) - 5/16" drill bit (not required) - 1/4x20 tap (not required but ideal) - 5/16" dowel rod (not required) - Press (vice or even a hammer would probably work) - Bar stock/wood to spread press load (a piece of 2x4 should work fine) - Grease - 1mm/.04" AK Flat w/ bent rails ### Procedure Use the 5/32" drill bit to widen the pin holes in the die body, punch, bar, and trigger guard holes on the receiver if you are using alignment pins. Use the 5/16" drill on the holes on the end of the pieces if you will be using dowels to join the pieces together, this is really only needed for the die body, the rest of the pieces can remain 'floating'. If you have the 1/4x20 tap thread the holes in the punch and bar, don't run the tap all the way through, just enough to get the threads started then use a wrench on the bolts to cut the true threads. If you have the guide pins use these to align the punch, bar, and flat while you bolt the pieces together. Make sure to mind the orientation of the punches, the punch and bar piece with 3 holes should be on the magwell side of the flat with all the recesses lining up with indents on the flat. See photos for correct orientation. Sandwich the flat tightly between the bar and the punch with the 7 bolts and nuts. Once this is together remove the guide pins if present. Grease the receiver, die body, and bar up, this should make it easier to remove from the die at the end. Place the receiver sandwich bar side down in the die body so the bolts will come out of the holes on the bottom of the die. Place the press piece centered on top of the sandwich, there is enough space for the rails to not contact the piece. Begin pressing, if you have a long enough bar stock to press on you can just press in the middle, if not move the bar stock around to get an even bend. Once the bar is bottomed out on the die body bending should be complete, there is no benefit to pressing further. Hammer the receiver sandwich out of the die using the large holes in the bottom. Once the sandwich is removed unthread the bolts and hammer the punch out from the mag well end, the receiver will bend out a bit as the punch comes out, this is fine, no bends are being put in the receiver. Hopefully you end up with something resembling an AK receiver. Shoutout goes to Tankoj for the inspiration from his HK jig. Freecad files are included if you want to change things. I used an AK-builder Romanian flat when designing this.