Repairing a bad drill job on a 80%er

[rdb241]

  Awhile back I purchased a 80% lower from Tactical Machining. I also bought there jig. Upon receiving my stuff, I put the lower in the jig. Clamped everything in a bench vise and started drilling the selector by hand. Well needless to say I messed it up. Not only was the hole not in the correct location but at an angle so the other side was way off. I work for a global airplane manufacturer and when a hole is drilled wrong they fix it with what is called a freeze plug. What a freeze plug is, it is a aluminum dowell that is slightly larger diameter than the hole you just drilled. Then they freeze the pug with liquid nitrogen or some other sud zero means. Then they press the cold plug into place and let it thaugh out. When it gets to ambient temp it swells for a super tight fit. Then the hole is redrilled correctly. If it works for airplane structure than why would it not work to repair the hole I drilled on the receiver? Well I did just that and it worked. I redrilled the selector hole using a drill prees and the hole is now perfect. I took some pics of the finshed hole and you can see where the bad hole was......I should have took pics before I started but did not think to. Enjoy the pics. I thought I would give everybody a heads up on repairing a bad hole.

[img width=810 height=607]http://i473.photobucket.com/albums/rr97/rdb241/photobucket003.jpg

[edgecrusher]

<thumbsup> , very cool and informative. Welcome to the forum.

[planeflyer21]

Welcome rdb241!

Good fix on that.

Jon

[IM_JOHNNYV]

I also had a snafu when drilling a 0% raw forging, but mine was from not reading the drawing correctly - duhhhh...... My fix was with some aluminum dowels and Loc-Tite®, but I very much like the "Freeze Plug" approach... Great job

[unforgiven]

Welcome from Indiana brother rdb,slick fix. <thumbsup>

[rdb241]

Thanx guys for the welcome. I have been building AK's for awhile and needed a different challenge.

[SDDuc996]

That was a great idea. Also, did you mill the sides of that lower (around selector and mag release) or do they come that way?

[rdb241]

That's the way the receiver came. I did take some 320 grit sand paper and kinda smoothed out the area around the new hole.

[SDDuc996]

Got it. Thanks bro.