rotor set screw extraction

[davem]

When I was doing my brakes a while back the set screw that holds the rotor to the wheel hub was completely seized (didn't have this problem with the rears at all). I had a choice between drilling off the head of the screw and waiting until the next day to finish the brakes so I did the former.

Obviously the set screw is not that important but I'd like to extract the remainder of the screw out of the hub because I have new ones and they're convenient to have. Should I just get an extraction bit that is smaller than the screw diameter and go for it? Any advice? I know that it probably wasn't a good idea to drill the head off but whatever.

[AT-JeffT]

I just went through this, Had to use 2 different methods to get both sides.
Methods:
dremel a slot for a screw driver(flat head)
drill and use a Screw extractor.

[jlevie]

There is nothing wrong with drilling off the head of the screw. If you stop drilling as soon as the rotor is free, vice grips on the remainder of the screw will usually avoid needing an extractor.

Or you can use a small sledge and hit the rotor from the back until it breaks off and then remove the screw.

[87-325ic]

thsoe little allens are such a bitch.

an impact driver was the trick for me.. hammer and turn, hammer and turn.

[KennyT]

Try and get vice grips on what is left of the stud. A little heat wouldn't hurt either. If that doesn't work, more heat and a screw extractor.

[davem]

There is nothing wrong with drilling off the head of the screw. If you stop drilling as soon as the rotor is free, vice grips on the remainder of the screw will usually avoid needing an extractor.

Or you can use a small sledge and hit the rotor from the back until it breaks off and then remove the screw.

Yeah I just drilled the head off, just wanted to get the damn brakes done. When I put the new screws in they will be coated in anti-seize!

[jlevie]

A common mistake when installing rotor retaining screws is to torque them down. They need not be more than finger tight. And by all means use metallic anti-seize on the threads and head of the screw.

[davem]

A common mistake when installing rotor retaining screws is to torque them down. They need not be more than finger tight. And by all means use metallic anti-seize on the threads and head of the screw.

Whoever torques them is a complete idiot, they don't hold the rotor, they're just there so that when you can take the caliper off and not have the rotor fall off the hub. Whoever did the brakes on my car previously is an idiot though...one of the caliper pins on the rear brakes was completely cross-threaded.

[davem]

What's better straight flute extractor:

or spiral flute extractor?

[Massive Lee]

I prefer the spiral flute.

A good trick is to weld a nut over the remaining thread. Heat will burn the rust. Then simply undo the nut and the remaining of the setscrew will follow.

[Jean]

drilling it out worked for me

[davem]

Here's what worked for me today.

Drill pilot hole into damaged screw stud. Heat the screw for 45 seconds with propane torch. Put some (candle) wax on the hot screw (youtube trick). Hammer in a straight flute extractor and reverse it out with a adjustable crescent wrench as a handle for the extractor bit.

I had a smaller spiral extractor bit that didn't work because it was too small but my dad suggested the straight flute and it worked after making a relatively large pilot hole and really hammering the bit in there. Welding some material onto the screw would be ideal but I've never welded in my life and I imagine it would be difficult because there wasn't much of a stud, the screw was pretty much flush with the hub.