Woodturning A-Z

Headstock.
The housing containing the bearings and spindle.

Heartwood.
Most of the section of the log with the exception of the sapwood and the pith.

Henry Taylor tools.
A famous Sheffield tool maker.

High Speed Steel.
HSS. Steel containing carbides of tungsten, vanadium, molybdenum and/or cobalt which has a high hardness and wear resistance. It will remain hard at very high temperatures. It is not to be confused with "carbide" as in carbide tipped tools or "tungsten carbide" etc. Most HSS turning tools are made in Sheffield, England from M2 high speed steel which contains (by percentage) 0.85 carbon, 4.0 chromium, 6.3 tungsten, 5.0 molybdenum, 1.9 vanadium and the rest iron.

Hollow vessels.
Vase shaped hollow pieces or very deep bowls. Requires special hollowing tools.

Hook tool.
A traditional turning tool which looks like a hook with a sharp edge. Works like a ring tool.

Hopus Measure.
A way of quickly measuring the size of a log.

Horsepower.
746 watts of power equal 1 horsepower. Motors are always less than 100% efficient but the output power is usually quoted on the plate.
370 watt = 1/3 horsepower
550 watt = 3/4 horsepower
750 watt = 1 horsepower