Bolt/stud extractors that aren’t made of cheese…
Discussion
I’ve snapped a pinch bolt doing some suspension work.
I’ve got half the bolt out using a cheap extractor set but they are really soft. When you hammer them in, they don’t bite and the threads get destroyed. They are softer than the bolt. I managed to round the end off just with light force and an adjustable spanner!
It’s a grade 10.8 M12 bolt. I have drilled a 5mm hole all the way through. (So it’s not the end of the world if I break an extractor as I should be able to smack it out from the other side.
It’s not a completely hopeless case. The bolt turned about 360 degrees before the head broke off but was needing about 100lb/ft or so to shift.
So I’m looking for recommendations for an extractor set that are made of properly hardened metal that will bite into the bolt and will let me apply at least a reasonable amount of force to get this sod moving!
I’ve got half the bolt out using a cheap extractor set but they are really soft. When you hammer them in, they don’t bite and the threads get destroyed. They are softer than the bolt. I managed to round the end off just with light force and an adjustable spanner!
It’s a grade 10.8 M12 bolt. I have drilled a 5mm hole all the way through. (So it’s not the end of the world if I break an extractor as I should be able to smack it out from the other side.
It’s not a completely hopeless case. The bolt turned about 360 degrees before the head broke off but was needing about 100lb/ft or so to shift.
So I’m looking for recommendations for an extractor set that are made of properly hardened metal that will bite into the bolt and will let me apply at least a reasonable amount of force to get this sod moving!
Nope. Replacing the shocks on a Rover 75. The bolt that clamps the hub to the shock broke when I tried to remove it.
The ones I have just don't bite if you just try to screw it in.
I got one half out by hammering the extractor in then heating the bolt and the hub up with a butane torch then turning the extractor.
The ones I have just don't bite if you just try to screw it in.
I got one half out by hammering the extractor in then heating the bolt and the hub up with a butane torch then turning the extractor.
The straight sided/hex style extractors seem to be the choice of people who don’t want to deal with this problem in their work.
US pro do a set.
Rather than using a butane torch, go get a mapp gas brazing torch and a canister of mapp gas.
The flame is about 1000c hotter and more concentrated, so you can put way more heat in to the female threaded portion and get it to expand and let go, before the heat spreads to the remains of the bolt.
Getting one of those when they were on offer at toolstation was the turning point in removing a VAG pinch bolt that I’d tried everything else on.
US pro do a set.
Rather than using a butane torch, go get a mapp gas brazing torch and a canister of mapp gas.
The flame is about 1000c hotter and more concentrated, so you can put way more heat in to the female threaded portion and get it to expand and let go, before the heat spreads to the remains of the bolt.
Getting one of those when they were on offer at toolstation was the turning point in removing a VAG pinch bolt that I’d tried everything else on.
The price looks cheap but I got these from Machine Mart and I have done a couple of jobs with the an they are very good
https://www.machinemart.co.uk/p/6-piece-screw-extr...
https://www.machinemart.co.uk/p/6-piece-screw-extr...
Tool review time!
Have we got the bolt out? Have we b
ks! We're up to 8mm on the hole now so something has to give tomorrow but I've given up for today.
Right.
Straight fluted extractors: Nope. Complete bust. They just don't dig in and the edges blunt. I suspect these are great for softer material but no good for hardened steel.
Irwin flute extractors: Holy crap these things are great. They grip immediatly and the amount of torque they can take is off the chain. I suspect the smaller ones need kid gloves but the 3rd and 4th ones are tough as balls.
Bosch Cobalt drill bits: These seem to be getting it done. I've been going low and slow with these, lots of lube and giving them time to cool between drills. I chipped the edge on one of them but the others have held up well. Cutting edge stays sharp and does make progress through the metal.
Have we got the bolt out? Have we b
ks! We're up to 8mm on the hole now so something has to give tomorrow but I've given up for today.Right.
Straight fluted extractors: Nope. Complete bust. They just don't dig in and the edges blunt. I suspect these are great for softer material but no good for hardened steel.
Irwin flute extractors: Holy crap these things are great. They grip immediatly and the amount of torque they can take is off the chain. I suspect the smaller ones need kid gloves but the 3rd and 4th ones are tough as balls.
Bosch Cobalt drill bits: These seem to be getting it done. I've been going low and slow with these, lots of lube and giving them time to cool between drills. I chipped the edge on one of them but the others have held up well. Cutting edge stays sharp and does make progress through the metal.
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