Anyone got a Machine Shop? Drilling Out / Pulling / Retapping a Bolt

[BlackAura]

So I ripped apart my roof rack last night, and we couldn't pull the remains of the bolt that sheared off  (we tried squaring off the sites with a file, heating it with a torch, and yanking it with vice grips).

So we brought it inside and started drilling it out, but we didn't have any reverse drill bits, and once we got to a large enough drill bit it almost looks like we're starting to see threads (they are very course, very wide threads, but I honestly didn't think we'd be seeing them at this point....figured we could go up another 2 bit sizes before we'd come close).

So at this point I figured I'd see if anyone on CJA runs / works at a machine shop and can help me either pull the remains, drill it out and retap it, or if there's some other method for doing this that you'd recommend.  I have an old / slightly rusty / slightly torqued copy of the bolt that's in the opposite side (to size the threading properly), although I'd like to replace the bolt entirely if I can.  Also the repair would have to be load-bearing, since it's for the roof rack.

I don't have the part with me today, and I have family visiting tomorrow evening, so Thursday is probably the earliest I'll be able to bring it in.

Thanks for any suggestions you guys have!

[Bnine]

Put a nut over it, and weld it on to whats left of the bolt. The combo of having the nut there, and the heat of the weld will get it out.

[BlackAura]

Do you have a welder? 

Unfortunately I'm lacking tools for this job

[vantagetes]

I have some easy outs and a tap and die set, how big of a bolt are we talking here?

[mrjeep4]

pm sent

[cLAY]

If you can see the threads then its too late, you've drilled it out too big. IF you have drilled it out PERFECTLY centered this might work. Get a very sharp pointed chisel and try to pull up the leading edge of the thread, if its drilled out JUST enough(you may have to drill a bit more) you'll be be able to pull up the top most thread and then the rest will uncoil like a big spring. I've done this successfully a few times but probably more often I've messed up the hole and had to install a helicoil.

Good luck! Try to post up some pictures, maybe we can offer some other ideas suck as just drilling it thru and using a nut on teh back or drilling it over size and tapping it the next size up.

[BlackAura]

Got a couple PM's regarding my problem, and it sounds like we'll be able to work on it Thursday, thanks for the suggestions and the offers of help guys.  Gotta love the Calgary Jeep Association, everyone's always willing to lend a hand!


cLAY, thanks for the suggestions as well!  I can maybe snap a picture or two tonight...the really weird thing is how much meat is left on what's left of the bolt.  We tried using a punch / hammer around the side to see if it would start to peel out of the threads, but that didn't work unfortunately. 

Also due to the way the bolt runs through the pipe you can't just put it into a drill press vertically, and center it.  As far as I can tell it's a piece of pipe (guesstimating an inch in diameter, don't have it with me), which has both ends cut off at approximately a 65 degree angle (instead of a straight cut, 90 degree angle).  Then a piece of steel or something was welded in each end, about 1/2" thick (again, guessing), and that was drilled out, right in the center, and tapped, and a bolt was stuck in (which is perpendicular to the end cut, so it's ~25 degree angle compared to the pipe).

...so we eyeballed it as best we could, punched in a dimple to start with, and then started drilling.