Drill or grind head off the bolt – usually works if just head damaged, not so successful when the thread itself is corroded as it doesn't leave much to turn the bolt shank with when removing it.

David J,

As OP stated countersunk, no room for grinder. All my inserts are held with Torque screws though

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KWIL … do you mean Torx ?

MichaelG.

CheeHi Michael

Sounds like you did the right thing. Heat is the game changer normally.

I've employed various tricks over the years on old cars et al, including your trick with the centre punch.

Welding on a nut through the bore with a stick welder works nicely if big enough – it's a double whammy; heat and torque. (That's torque michael G not Torx ) 😀

Also, heating the centre of the screw head to red and belting in a screw driver or over size allen key … or Torx driver tends to work well.

Also drilled off the heads and applied mole grips to the stud when desparate, if countersunk and not too hard.

Cheers Will

But ………

The one thing that has NEVER been successful for me is those damn near useless screw extractors.

Never, not even once have I got those to work !!!!!

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I have an interesting "opportunity" which I keep putting off.

When I bought the ML7R, it came with a Myford-Dickson QCTP … One of the toolholders has stud for the adjusting screw sheared-off, just under flush.

One day … When I'm in the right frame of mind …

MichaelG.

… It does make quite a good paperweight, Will

MichaelG.

spark erode a hex socket into the stud?

Hi Michael, it depends on what diameter the stud is, but if you have a TIG setup and can do some delicate building up, you can place a washer with a slightly smaller hole than the threaded hole, over the stud and build the end of the stud up enough to get a pair of grips onto it or weld a nut on, the washer will help, depending on the skill level, melting into the thread. This same method can be used for countersunk screws. A little patience is a bonus for this method, but with a good skill level, or finding someone who has the skill level, it is doable. I have done it with a 6mm broken stud and down to 10mm using MIG or stick.

If your QCTP is no use as is, then what is there to loose, it would still work as a paper weight

Regards Nick.

One way of loosening 'seized' or similar screws is to use impact, but scientifically. Find a short bit that fits, or chop off a short length of new, sharp, allen key (etc). Then hold it in place with long-nose pliers and smack it firmly into the reluctant screw. This should have two results:

1. The thread is jolted from the tight side to the loose side, crumbling any rust, etc.

2. The metal forming the bearing face of the screw, or the part, or both, is distorted – knocked down, giving a tiny clearance.

With any luck this will allow you to turn the screw. Impact drivers do this, and apply a torque at the same time, but finding the right size of insert is not easy (except for the Phillips screws that were the most trouble on 1970 era motor bicycles).

I have seen the same trick used to smack the head of a too-tight filler plug, too. One good hit was enough.

Hope this helps.

Regards, Tim

On a similar job I used a slitting abrasive disk in a dremmel type tool. I cut straight across the top of the stud, slotting into the parent metal on both sides until I'd got enough depth in the broken stud. A conventional flat bladed screwdriver then extracted the stud.

In your case, I wonder if it was loctited in though, in which case some heat may be advantageous before unscrewing to prevent opening out the end of the stud to make it even tighter in the hole.

I had a screw I couldn't get out and it was going to be difficult to get one that matched. I ordered a left hand drill from Drill Services stuck it into the electric hand drill, lots of pressure and fired it up. Much to my amazement it immediately unsrewed and hardly damaged the screw at all. A large hardened JIS head, I keep meaning to order a couple of other sizes. They seem to hard and are end ground.

I have removed small broken studs with a Dremel and cutting disc. Usually deep enough to get a neon screw driver well in. Biggest problem is making sure the bits of cutting disk don't hit me or some one else. The trajectory is consistent. A LH drill might be easier. Maybe followed by a LH tap or tiny screw extractor. Probably best to use a left hand drill and loctite a bit of bar in, bent if needed. I have managed to remove a rather large rounded off hex headed plug by drilling 2 holes and fitting dowels and then closing an adjustable spanner over them. I had to add a 3ft or more length of tube to get enough leverage. That nearly needed my body weight.

Drill a head off with a rh hand drill and sometimes the head shears off. If not it's been tightened pretty firmly – head against a surface so the remaining part aught to be loose when the head is drilled off.

If some one has one an oxy acetylene torch is unbelievably effective at loosening rusty bolts. The head of a bolt heats to red very quickly. Do that and they unscrew easily.

As mentioned put the driver in and give it a hefty whack with a hammer. That often loosens screwS, popular when slot heads were cut for fixings, also hollow ground blades. The hollow only needs to be a few thou.

There is a couple of problems with small hex sockets – wrenches made out of air hardening toffee and it's interesting to measure the actual size on a lot of them. They are supposed to fit rather precisely in very small screws. Best thing to do is change them to torx while the wrench still works.

John

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