While at the university, one of my sons took a course called precision
engineering or something like that. In this class one of the things they had
to do was lap two pieces of steel until the steel was so smooth that when
you placed them together, they would take suction on each other and had to
pulled apart .
I never thought much about it until recently. A while back I was in the
local Woodcraft store and they had 10% off everything in the store sale
going on. In my befuddled state, I came home with a Lie Nielsen 4 1/2 hand
When I take the iron out of the plane to hone it a bit, the iron and chip
breaker take suction on each other and I have to slide them side ways to
separate them. I don't know how they accomplish it, but I'm impressed.
The plane is a delight to use.