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Discussion Starter · #1 ·
I tapped all of my (front) trunion holes with no problem.
When It came to the rear trunion the 10-32 tap is to small for the damn hole! The screws I've purchased are for 10-32 for the trunions and the hole is to big, I (don't) want to tap for a 1/4" screw. Some say I have no choice but I'm looking for a second opinion.
Could I fill the holes with jb weld than tap for my 10-32?
Could I use some type of shank or insert than tap with a smaller size?
Exactly how much pressure is going to be on the force of the rear trunion?

I was even thinking of filling the holes with (JB) than setting in the receiver, putting the screws in than just letting it cure.
What's the diffference if you use rivets would'nt it be the same principal?
Please give me some advice guys, I don't want to go bigger on the screws.
I've spent to much time to make this a tacky lookin build with fat headed screws in the rear trunion.
Thanks....Shadow
 

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too big

tap it 1/4-28 then go to mcmaster- carr on the net and buy some helicoils.they are little threaded inserts that are used to repair/restore threads.I'm new to this gun stuff,but I know they work on engine block heads and exhaust manifolds they're tough bastards. they won't let you down.
 

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I think the helicoils for 10-32 would be to big to fit in the rear trunnion.
 

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prophet said:
tap it 1/4-28 then go to mcmaster- carr on the net and buy some helicoils.they are little threaded inserts that are used to repair/restore threads.I'm new to this gun stuff,but I know they work on engine block heads and exhaust manifolds they're tough bastards. they won't let you down.
I used one helicoil on my front trunion block and one on the the rear trunion. They are very expensive. You have to drill one size larger and then use 10/32 helicoil. They work great!:) OH! You can buy them at NAPA AUTO PARTS.
 

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how about a 12-32 screw??? it is between a 10 and 1/4" . I think I would go for a 12 to repaire damaged 10's, why not just use 12's??
 

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I thought about using HeliCoils for a repair on a trunion, before I removed a broken tap. I thought there would be no problem as HeliCoils are used in a lot of applications to repair threads.
Here's the problem, right from the HeliCoil product Catalog:
"The minimum material thickness for through hole assemblies is equal to the Insert Nominal Length without a countersink and the insert 1/4 to 1/2 pitch below the surface. "
The end result is a minimum required material thickness for a 10-32 of 0.190" plus 0.031" or 0.222" (Screw major diameter plus 1/2 thread top and bottom of the hole).
None of the trunion holes are near that thick as I measure them, which means that the HeliCoils will NOT hold as they are designed to.
I would recommend that you rethink using HeliCoils, because even if you get them to stay in place, they are not holding with anywhere near the same strength as the other screws are. I doubt that anyone here wants to shoot their AK,and end up getting that close a look at the front trunion.
 

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Have you thought about filling the hole with a weld and then tapping it again. The metal would be hard, but would probably work.

Or, you could get a long rivet and put it through. Hammer it down a bit so that it expands and then cut the ends off. Then drill your hole through the rivet and do it like you did your front trunnion screws.

How about drilling entirely new holes in the rear trunnion, unless you've already drilled the receiver holes or are using a pre fab'd receiver.
 

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Discussion Starter · #8 ·
-Rear trunion-

I drilled a new hole in the receiver, than used a quick metal repair reson hardener almost like "JB" and it worked great!
Thanks guys...Shadow :thumbup1:
 
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