Messed up threading rear takedown

[Eric P]

So as I have done on all my ARs, I was threading the rear take down spring hole when the tap snapped on a new lower.

Any good machinist that could drill out and remove the tap?

If not is there a takedown pin option that doesn't require the sprung pin?



Thanks

[Graves]

There are tap extractors that basically grab the broken piece by the flutes to bring it out. Not sure how small they go as I only have them down to 1/4".

[Fentonite]

http://www.knsprecisioninc.com/gun-p...n-250-dia.html

[Great-Kazoo]

So as I have done on all my ARs, I was threading the rear take down spring hole when the tap snapped on a new lower.

Any good machinist that could drill out and remove the tap?

If not is there a takedown pin option that doesn't require the sprung pin?



Thanks

The problem with a broken tap is. they are usually harder than basic drill bits. I'd file the broken tap flush and use the KNS pins.


http://www.knsprecisioninc.com/gun-parts-and-accessories/pivot-takedown-pins/ar15-m16/push-button-pivot-pin-250-dia.html

[SAnd]

I sorta used this method years ago to get a tap out of aluminum. I didn't use heat so it took a couple days to dissolve it enough to wiggle it out. The aluminum piece was bare so I have no idea what would happen to Parkerizing or other coating. I bought my alum at a Safeway spice area.

https://www.youtube.com/watch?v=JCADI0YSt8M

It looks like there is at least one more video about this on there.

[powerstroke79]

I used this on a motorcycle case once. Not cheap but worked good

Tap-X Broken Tap Removal Kit

http://www.chemical-supermarket.com/...?productid=574

[Eric P]

Got some alum and added it to boiling water. Tossed in the remaining part of the tap and it fizzled until the water cooled. Didn't look like it did much other than turn it black.

Reheated the water and tossed in an old scope ring to see what would happen to the anodizing. After an hour, the anodizing would come off just from touching it. Washed and rinsed the ring and the anodizing came off.

So I'll just get the push button pins.

I put the tap back in the alumni just to see how long it would take to dissolve.

[Erni]

Not sure how big thst tap is but I had luck grinding a broken .125" tap out from a hole in metal. I used diamond coated dremel tools. There was a ball end one and a toothpick shaped bur. The bur nested between the tap flutes and did most of the work. Pain in the arse it was and took lots of time. I think the tips were from a cheap harbor fright dremel set.

[Eric P]

It's a #4-40 tap.