Originally Posted by
operator
With the 14mm bolts that are on the cranks. I really doubt that extractor will be able to remove it.
OP: We've removed cranks at the shop where the crank didn't need to be saved - 1 minute with an angle grinder on an AL crank is all that is needed to remove it.
That is just an example.. they come in sizes for removing bolts from M4 (smallest) to M30 (this is some serious stuff!). They have tapered left hand thread that as you turn them into the loosening way it will bite into material of the bolt, wedge itself in, lock into place and for sure it will at some point turn the bolt loosening it. The size of this thing is accordingly to the size of the thread not of the head.
Works every time, I have used it numerous times especially in broken bolts to remove the rest of the bolt still inside. Well that's why it's called a SCREW/BOLT EXTRACTOR