Originally Posted by
rootboy
So you couldn't easily use the simple bolt idea! I'd be interested in knowing what your two handle threadings measure. I measured my old tool, and came up with the 9/16 X 24, which is nearly impossible to find. But it looks like, viewing JDT's pics, that they changed the spec through the years, for some reason. No idea how old my tool is.
I guess the threads per inch on the bolt will affect how the tool works and how "quickly" it extracts the crank, of course. I wonder if there is any mechanical, or safety advantage, to the finer threaded bolt.
Well, sure. The finer the thread, the less force is required to turn it. Some people stop trying when they reach a certain level of difficulty. Crank extraction is especially tricky, because it gets progressively harder, and then it suddenly gives. I've taught it a lot. It's not intuitive.