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Discussion Starter · #1 ·
OK, guys, here's what I did...
1.
a peice of flatbar, stainless steel, 1.245"wide by 5/8" thick, 13 inches long. cold rolled steel would be fine, but this is what I had at hand.
2.
same 13" length of 1.250" square tube, stainless. again, a length of good, heavy cold-rolled, hot-rolled, carbon steel square tube, or heavy 1-1/4" channel iron will suffice for this piece.
3.
I laid a TAPCO flat onto the flatbar, eyeballed center, and marked all of the openings in the flat onto the flatbar with a Sharpie marker. I then found center on the flatbar, and drilled 6 holes down the length, so when I stick a bolt through, the bolt will go through the flatbar, and through the existing openings in the TAPCO flat.
4.
I then laid the flatbar on top of the square tube, evened up the ends, and transferred these drilled holes to the square tube. The square tube got drilled with a Q letter drill, and tapped to 3/8" fine thread. The holes in the flatbar were drilled out to 25/64".
5.
The flatbar received a couple of notches on the side to accept the dimples of the flat when it is rolled up. the dimples are a bit oversized, approximately 1/4"deep, and 3/4" long. I did this on a mill, laying the flatbar down in the vice flat, and drilling a 3/8" endmill down so that a portion of the end mill was hanging over the edge, stopping about 1/8" from going through the back, then plowing out a slot about 3/4" long. I did this on both sides.
6.
I flipped it over, and milled out a portion to accept the magwell lip. this step and step 6 could have just as easily been done with a dermel or grinder, but why not use the mill when you have one nearby?
7.
I took the TAPCO flat, and laid it onto the square tube, aligning the holes, and then laid the flatbar onto the TAPCO flat, aligning the recess for the magwell lip and the drilled holes, put the bolts in, and finger tightened.
8.
using my calipers, I measured, tapped, and re-measured, centring the flat exactly on the flatbar, then took up some torque on the bolts, and re-measured. I cranked the bolts down really tight, and measured one last time. I now had my sandwich.
9.
I stuck the sandwich in the vice, cranked it down super tight, and using a 2x4 scrap and 32 ounce ball-pien, began tapping the edge of the flat down, going back and forth, checking to make sure it was going evenly. I think I like bending the edge this way for a couple of reasons...
the finished result is a very sharp radius, folded over the edge of the flatbar, not stretched into shape. there is very little, if any stretching of the metal. you can also see the progress at all times, and can give your attention to one small section at a time if you need to. you are not blinded by pushing it down into a die.. when the process was complete on one side, I simply flipped it over and repeated for the other.
10.
loosened and removed the bolts, gripped one protruding end of the flatbar in the vice, and just kind of gave the receiver a little twist, and it popped right off.
11.
I took my calipers, locked them on the measurement for the front of the receiver interior (1.170"). and scribed a line where the top rail will be bent, measuring from the inside bottom of the receiver. same for the rear interior receiver measurement (1.620").
12.
I then took my flatbar, inserted it into the receiver, and C-clamped it on the scribed lines. I then put the receiver in the vice with a couple pieces of 3" angle iron laid over the vice jaws for support, and to make the jaws longer. Then evening all of this up , so that the angle iron and flatbar are flush, with the metal for the top rails sticking out, I cranked the vice down super-tight, and hammered with my block again, in the same fashion as I did the sides.
Next step is to find yourself a kit, build it, finish it, love it, and do it again!
 

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Discussion Starter · #3 ·
I have more pics of various steps in detail... let me know if you need more info or more pics detailing a certain step... I'd be more than happy to help any one of you!:thumbup1:
 

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Great job and very simple! Time for some production runs!
 

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man it dont get any easyer. my reciever came out great with razor sharp corners and fun forming it too
 

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Thanks for the pics!! Just think how far building AK's has come since Max first posted his tutorial(still the best on the web, especially for using a bent blank).
 

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SKS Hunter, Thanks for the inspiration. I had figured out a way to make the parts for one of the press operated jigs, but I don't have a press, and actually my garage is so full of stuff, I don't have room for one. A hammer and block of wood now, those I already have.

:thankyou: Got to run, I have a Tapco flat I bought from DPH Arms today!!!
 

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Discussion Starter · #12 ·
hcpookie... The square tube does have a rounded corner, but since this is not what you are bending the flat against, it doesn't much matter. But I do agree... flat bar stock would be best to hold down the edges as tightly and as closely to the folded corner as possible. I have used the square tube and flat bar, and both do well.
 

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Discussion Starter · #13 ·
update....
there have been about 10 flats bent with this "jig" here at my home, and each one has come out beautifully.
I've even bent a couple of stainless steel blanks for a Bulgarian SLR kit I have. still don't know if I'll use them, but maybe...
 

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cephus
if you want a flat this is a great way to go. if you take your time it comes out great. and the jig in not that involver to make.
 

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Discussion Starter · #16 ·
no I didn't, Randy... they are way to easy to make, and I wouldn't feel right about taking anyone's money for something that can be whipped up by anybody with a dremel in about an hour with a couple bucks worth of steel. I may be able to make a couple up, if needed, for just the material costs if anybody needs it, but I don't want to go into full-blown production of anything but my own AKs. I also had some ideas of improving it, with hotbarrel's help, and will probably do that soon. we were thinking of instead of just a peice of flatbar for the inside, making a wedge shaped like the inside dimension of the receiver, with a slot running the length for the dimple, so you could just slip it out when finished. I might try with some hard UHMW or Hyfax plastic at first, just because it cuts like butter.
 

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That's sort of what I had in mind for the one I proposed a few weeks back except the cut was for the rails. If you add some locator pins I'd be in for one if you want to whip one up to see how they work ;)

I have no source for steel and while I have some metal working ability I'm lacking tools and something to work from.
 

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Hi all new to the form. I have two questions and one coment, for sks hunter, what gage stanles did you use, and did you use a print off of the web to make the bending jig??
Randy you must stop the toon from bouncing I cant stop watching!!!
 

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Discussion Starter · #20 ·
as for the stainless thickness, I used 1.0MM thick stuff (really heavier than needed), andf it bent really hard, but I got one good workable blank with great corners and dimensions.
As for the bending tool, the print I used just came from my thought process. I was trying to think of a way a guy could bend one without spending alot of dough on a jig and press. done with only a vise, a dremel, drill and tap. If you have a steel distributor around where you are, then you can make one for yourself in about an hour or two, and have it for as long as you feel like bending. I figure the cost to be just a fraction of what a jig costs, and then you need a press....not to mention there are alot of guys here who live in apartments, with no room for a press. It could probably even be done with no vise at all, but would be rather cumbersome.
Not trying to knock the guys who are selling the jigs, they are really well made, and do a wonderful job.... just trying to give folks another way without coughing up the greenbacks. I have a couple of AKs on receivers that I bent this way, and they are beautiful. nice crisp, sharp 90 degree corners, and you don't have to slather them with grease.
 
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