cylinder hone is a tool, usually consisting of two, three, or four
replaceable abrasive stones at the end of spring-loaded arms, which
is spun around and moved up and down a cylinder's bore to remove
light rust, corrosion, and built-up residue. Outward pressure is
exerted on the stones, as a result of which they remove some material
from the bore as they rotate. The spring tension is adjustable to
maintain the proper stone pressure against the cylinder walls. The
grade of stones to be used is normally specified by the manufacturer
of the piston rings. Honing stones are classified by grit size;
the lower the grit number, the coarser the stone.
Cylinder honing machines are available in manual and automatic types.
The latter have the advantage that the exact required crosshatch
angle can be dialed in. When honing a cylinder by hand it is important
to use a slow-speed (200-450 rpm) electric drill.