Has anyone used the Grabit screw extractors or any other brand of them?
I've read the reviews at Lowes.com and there seems to be an equal mix of good and bad experiences with the tools.
I need to get a bolt out of the cranks on my mountain bike, but I don't want to waste money, or break the tool off in the bolt. Then I'll have to buy a set of cranks instead of just a new bolt.
I don't know the bolt size, I do know it's around a 1/4". I'm thinking the smaller the bolt, the smaller the extractor, more the chance it will break off, so I'm trying to find out the quality and durabilty of the extractor.

 

Don't know anything about them, but I looked it up, and it looks like it's only for biting into a stripped screw head. If that's not what you've got, it won't do any good.

Easy outs are the classic for something where the head has snapped off. People swear by them and at them. They CAN break off in the bolt.

Stuck fasteners are always a crap shoot. PB Blaster, heat, and believe it or not, wax can all work sometimes. The wax trick is really surprising. Just drip a candle onto the bolt -- apparently some of the wax works its way down and reduces friction. It worked the one time I tried it. Probably best AFTER you've used PB Blaster or something like it .

Good Luck,

hj

 

the wax trick does work, i was amazed when an old timer showed it to me about 40 years ago. my problem is i don't keep candles around.
if there is any of the bolt head accessible, i just weld a nut on it and the heat from welding the nut on usually does the trick to get it out.

 

If it's a standard thread, use a reverse drill bit. Usually once the bit starts biting in the piece that's left it'll back right out. O'Reilly auto parts carries a set of these.
If it's reverse thread just use a standard drill bit.

 

broken bolts... stuck bolts.. lots of reasons.. and lots of tricks.

best penetrating oil, acetone and automatic transmission fluid.. 50/50. let it set overnight but spray it several times over a few hours.

next try ...drill hole thru bolt.. heat from a propane torch... easy out tool.