Skip down to 3:00
http://www.youtube.com/watch?v=m_-iPpEuWRA

I don't know if, technically, they are _slip_ rolls, since I don't see
how any of the rolls would open. Still interesting, though, & much
simpler than most. Especially using the cranks & link in place of gears
or sprockets & chain.

The action is somewhat different than the usual slip rolls in that the
material is not pinched between drive rolls.

Is there a specific name for this type of roll?

Bob