Originally Posted by
Hopping_Rocks
The lock ring still has the flats. I tried using a pipe wrench but the lock ring is so thin that the wrench can't get a very good grip on it. I tried using a vise, but when I push/pull on the crank arms all that I end up accomplishing is getting the crank to pop out of the vise.
How would I go about using a hammer and flat punch? Is the lock ring right or left-hand threaded? (can't remember right now)
You need a better vise, like a machinist's vise whose jaws will stay parallel when tightened, though at this point you may have damaged the flats enough that it won't work. The LBS may or may not have a wrench that will fit the locknut - most would use a vise or large adjustable wrench. The hammer and flat punch was only if the locknut had notches instead of flats.