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Dan Forman
07-02-2005, 6:16 AM
Can someone explain the procedure for removing the embedded portion of a sheared bolt from it's hiding place? It's a 1/4" brass bolt in a steel bar, sheared off even with the surface of the bar, leaving about 1/4" of the bolt remaining in the bar. It shouldn't be stuck (wasn't broken by twisting). I need to preserve the threads, can't drill it out and tap it a size larger. Thanks.

Dan

Kirk (KC) Constable
07-02-2005, 6:20 AM
Can you stick something to it to unscrew it? Super glue or JB Weld?

Larry Reimer
07-02-2005, 6:44 AM
Dan, along the same thinking as Kirk's suggestion, I have had success with laying a hex nut over the sheared off bolt and then brazing inside of the nut to the sheared off bolt and then you have something to grab to remove the bolt. You could also try drilling the center of the sheared off bolt out and drive in a small EZ-out.

Tony Falotico
07-02-2005, 7:36 AM
Dan, they make a reverse twist drill bit, the threads are reverse of normal so it drills in the opposite direction of a normal bit. If the bolt is big enough to drill into and is not frozen, just drill it with the reverse thread bit. Once the bit grabs it will spin the bolt right out. I've done this successfully several times on bolts broken in engines. A good hardware store should have the bits, perhaps an auto supply, Not sure if the borgs would.

Michael McDuffie
07-02-2005, 9:53 AM
Good morning Dan,
Sometimes you can tease the screw out with a dentil (dentel?) pick or small screwdriver. The trick is to apply firm pressure but not jam the screw in the threads by pushing sideways. Sometimes its enough to just press your thumb hard on the screw and twist.

Or, head to the hardware store or sears and ask for a broken screw extractor set. It's gonna cost as much as $45 for four tiny little left hand drill bit/extractors but they can save an expensive bit of machinery. If you go to sears they sell two kinds, one is for removing screws with stripped head from wood, these won't work for you.

If both sides of the part are accessable, you can drill from the back side with a small bit. Use one small enough that it won't hit the threads. The heat from drilliing along with the friction will sometimes drive the screw out. If you go from the front side, the burr where it sheared will bind and the screw won't come out.

Good luck,

Michael

Jason Roehl
07-02-2005, 11:34 AM
I've had success drilling out bolts with just regular-twist drill bits. If you select a drill bit that is just a hair smaller than the minor diameter of the threads, the bolt will often just "snake" out of the hole as you drill. Being a brass bolt, it should be pretty soft and easy to do.

Cecil Arnold
07-02-2005, 12:51 PM
They make something called an EZ out extractor you should be able to find at the BORG or an auto parts place. You drill a small hole in the bolt then put the EZ out in and unscrew it. The only potential problem may be the size of the bolt.

Dan Forman
07-02-2005, 3:46 PM
Thanks to all for your advice. Since the bolt wass accessible from the far side of the bar, I was able to free it by with a small, standard twist bit, came right out after the bit had worked into it a tad.

Randy Meijer
07-02-2005, 10:25 PM
Just for future reference, when you have a little bit of bolt sticking out; but not enough to grab with....ViceGrips, for instance....you can take a hacksaw and cut a notch in the end of the bolt and then use a screwdriver to remove the bolt. This only works if the bolt is not too seriously stuck in the hole. A drop or two of WD-40 or other penetrating liquid should also be applied.