80% build mistake - Page 1

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Posted: 10/18/2014 8:45:05 PM EDT

So I thought I finished my first 80% build but as I went to assemble it I realized that the rear trigger pocket had been opened up a few thou too wide. The hole where the spring/detant for the safety should be is now open to the trigger pocket. My thought is to plug the hole for the safety with plasticine and build up the area with JB and re drill.

Any thoughts or words of wisdom or do I have a paper weight?

thanks

Bush

Posted: 10/18/2014 11:22:33 PM EDT

[#1]

Ouch, I had one that barely broke through there once, but it still had plenty of meat to hold the detent securely in place. It's a dedicated 22, but I haven't had any issues with it.

Unfortunately it looks like you took out a bit more. You could try to drill and tap the hole then loctite in an aluminum screw. Then cut it off, drill it out for the dentent and clean up the inside with the mill. JB weld may work just fine, personally, I try to avoid it. YMMV and I'm checking back for others suggestions.

Posted: 10/18/2014 11:49:08 PM EDT

[#2]

Jewelers torch and some aluminum welding rod?
also looks like you forgot to do the rear take down lug pocket.

Posted: 10/19/2014 11:43:24 AM EDT

[#3]

there's a two part epoxy putty named Kwik Steel, (around here)
its in tube form, you cut off a portion and mix it by kneading.
it isn't runny and will fill in that area so you can re machine it.
it'll work fine, that's a very low stress area.

Posted: 10/19/2014 11:59:22 AM EDT

[#4]

I have an old Sendra lower someone had busted that portion out trying to bang the selector out not knowing how to remove it. I cut some shim metal to cover the whole gap, sleeved the open side of the hole, and expoxied it all in place.

Posted: 10/19/2014 12:35:09 PM EDT

[#5]

chalk it up to the price of learning.

I lost a 80% lower when the end mill slipped in the collet. I scrapped that one.

Posted: 10/19/2014 1:55:53 PM EDT

[#6]

You'll be fine, but put in a selector with detention and rest it.

Posted: 10/19/2014 4:35:39 PM EDT

[#7]

I'd use JB weld.

Posted: 10/19/2014 9:45:29 PM EDT

[#8]

Quote History

Quoted:
You'll be fine, but put in a selector with detention and rest it.

View Quote

you know, i might actually work ok just like it is, more than half the circumference is there.
it's definitely worth testing, nothing to lose.

Posted: 10/20/2014 12:07:01 AM EDT

[#9]

i don't think your even close to done cutting. that pocket has to go way back..

Posted: 10/20/2014 12:42:13 AM EDT

[#10]

Quote History

Quoted:
i don't think your even close to done cutting. that pocket has to go way back..

View Quote

Came to post this. There's no pocket cut yet for the rear lug on the upper. Be sure not to cut that part too wide or your upper/lower fit will be wobbly.

Posted: 10/20/2014 1:29:56 AM EDT

[#11]

Even the Canadians are building 80% lowers! Good work, OP. 87% of ARFCOM has never even tried to drill an 80% lower.

[ARCHIVED THREAD] - 80% build mistake

AR-15 » Build It Yourself

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