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leroy
September 12th, 2005, 11:12 PM
Anyone know how to deal with stripped allen bolts? My headset cap bolt (5mm) and stem bolt (4mm) rounded when I try to loosen. Them suckers are too tight. I didn't count on this while trying to squeeze in a new fork install prior to a midweek trip to West Virginia. I've tried forcing an equivilent english allen wrench, but this ain't working. Do any tools exist? Somone have any ideas? This sucks. Thanks.

CountZero
September 12th, 2005, 11:48 PM
Leroy -

Prepare the area with a good penetrating oil, like WD40 or Loctite Penetrating Oil.

Then, go to town on those little bastards with a couple of left-hand drill bits, such as those sold under the brand "Easy-Out".

See http://www.toolprice.com/category/screwextractors/

Best wishes,

T

jabberwocky
September 12th, 2005, 11:48 PM
Anyone know how to deal with stripped allen bolts? My headset cap bolt (5mm) and stem bolt (4mm) rounded when I try to loosen. Them suckers are too tight. I didn't count on this while trying to squeeze in a new fork install prior to a midweek trip to West Virginia. I've tried forcing an equivilent english allen wrench, but this ain't working. Do any tools exist? Somone have any ideas? This sucks. Thanks.
What you want is a screw extractor. McMaster-Carr (http://www.mcmaster.com/) sells several varieties. The basic premise is that it is a tapered, reverse threaded screw. You screw it into the stripped allen, and since it is reverse threaded, it unscrews it as you tighten down.

Note that if the screw is seized (the metals have bonded together) then this probably wont be enough to get it out. This is why they tell you to put grease in there. :) At that point your only option is probably to drill the head of the screw off. Note that this can be a little dangerous, since the screw is under pressure and the head is gonna shoot off when it breaks free. Also, this will leave the threads of the screw inside whatever it is they are in, with no easy way of getting them out.

hophead
September 13th, 2005, 11:57 AM
You may also be able to cut a slot in the top of the bolt with a Dremmel tool and then remove it with a flat head screwdriver.

ODG
September 14th, 2005, 07:59 AM
I've used a drill bit and one of those extractors jabberwocky posted many times. You can also buy the bit and an extractor in various sizes together in a package at the Home Depot. They usually work great but here are a few tips I've learned. Use a very slow drill speed when drilling the pilot hole for the extractor and take the time to get the bit centered as good as possible. The bits size you'll need will be very small and it is so...so easy for the drill to twist the bit in half the first time it bites into the metal. Also be sure to work the extractor in by hand with a small wrench, I tried using a drill to power one before and the result wasn't pretty.

If you're not planning on using your old fork again you could always attack the steer tube with a hack saw between your stem and the head tube. ;-)

hophead
September 14th, 2005, 08:07 AM
Be very careful using screw extractors (easy out etc.). They have a nasty habit of breaking off in the screw to be extracted. Then you're left with a hardened piece of steel stuck in the end of your threaded fastener. These should only be used as a last resort.

ODG
September 14th, 2005, 08:14 AM
Be very careful using screw extractors (easy out etc.). They have a nasty habit of breaking off in the screw to be extracted. Then you're left with a hardened piece of steel stuck in the end of your threaded fastener. These should only be used as a last resort.

That's exactly what happened to me when I tried using the extrator on the end of a drill. I ended up breaking 3 drill bits trying to drill the piece of extractor out.

langer
September 14th, 2005, 08:46 AM
You may also be able to cut a slot in the top of the bolt with a Dremmel tool and then remove it with a flat head screwdriver.
i second this method, used it several times. you can also use the dremmel to flatten two opposing sides of the bolt to use with a wrench.

dustyvelo
April 29th, 2012, 08:31 PM
I searched the threads hear for information as I prepare to extract the bolt I just stripped that holds on my brake lever - Avid Speed Dial. The soft allen head didn't like it when I did set the wrench deep enough before rotating. I am liking Scott's idea of cutting a slot in the bolt so I can use a screwdriver.

This sound like the right approach for this particular problem? I have extractors, but the soft metal doesn't strike me as though it would grab well.

Thoughts?

langer
April 30th, 2012, 12:25 PM
I searched the threads hear for information as I prepare to extract the bolt I just stripped that holds on my brake lever - Avid Speed Dial. The soft allen head didn't like it when I did set the wrench deep enough before rotating. I am liking Scott's idea of cutting a slot in the bolt so I can use a screwdriver.

This sound like the right approach for this particular problem? I have extractors, but the soft metal doesn't strike me as though it would grab well.

Thoughts?

Extractors, like was said above, are a last resort in my opinion. I would cut a slot with a dremel, like you said, and use a screwdriver. Worst thing that could happen is you end up removing the whole head and then use an extractor on the remainer of bolt, which should come out since there won't be any tension on it with the head gone.