Joe Pfeiffer wrote:
jim writes:

Joe Pfeiffer wrote:
Beryl writes:

Christopher Tidy wrote:
Beryl wrote:

Positioning the vise-grip jaws one facet to the left would let the
"leading edge" of the nut (that follows the cut) dig in for a
better bite.
And maybe damage the stud, which I badly needed to avoid!

Chris
?
? I did a crummy job, describing the edge literally digging into the stud!
?
? The way the pliers are positioned in the pic, clamping pressures are
? as close to the trailing edge, and far from the leading edge, as they
? can be. The split nut is pushed around from behind, tangential force
? wanting to lift the rear of the nut off the stud, "unwrapping" it.
? Move the clamping pressure close to the leading edge and the nut will
? wrap as it's pulled, closing more tightly around the stud.

It's hard for me to imagine this making a significant difference.

A chain wrench, strap wrench, oil filter wrench, pipe wrench, vise-grips
as in the picture, etc., are made to work well in one direction.

? A situation where a split "stud" grabs the nut around it...
?
? Think of drum brake shoes. When forced outward, the leading edge of a
? shoe wedges tightly against the turning drum. A trailing edge forced
? outward isn't very effective.

That isn't how self-energizing brakes generate extra friction --
friction against the drum rotates the shoe assembly forward, and the
front shoe works to push the rear shoe harder against the lining.
Yes, it is the trailing shoe that applies the most force against the
brake drum.

Right -- but it isn't because the leading edge is wedged against the
drum.

I'm thinking of motorcycle front drum brakes, which evolved to
dual-leading shoe designs with two cams, lifting the leading edges of
both shoes.
And then, they had very little stopping power when rolling backward,
which didn't matter anyway. They worked significantly better in one
direction.

In this case, I think the grip on the nut slipping or the stud snapping
will happen before the nut turns on the threads.

Agreed.

I snap the stud, absolutely.