Hand Tools

Subject:
Speaking of which, Bill,
Response To:
Well, thanks yet we also ()

Wiley Horne
I tried to repeat your unexpected finding that the dull side of PMV11–the supersmooth side—showed the highest friction coefficient.

I got the same effect, though just qualitative. Planed a board edge to a gloss, then raised it to a ramp, and adjusted the ramp angle to where the shiny side of a PMV11 blade just started to slide. Then flipped the blade over to the dull side. In repeated tests, the dull side would cling at an angle where the shiny side would slide. And when I found the angle where the dull side just started to creep, the shiny side took off at full speed.

What it means...dunno, but we do know that the dull side has a considerably greater ‘real contact area’ than the shiny side. But the closeness to the wood is not enough to create adhesion, which requires nanometer closeness to happen. So it seems to be some sort of surface effect different from the gross ‘rougher=more friction‘, but not yet an atomic effect.

Now who’s off chasing extraneous information?? :) :)

Wiley

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