thou
thou
Lengthexact by definition
A thou is one thousandth of an inch, exactly 25.4 micrometres. It is the working precision of machining and sheet metal: a general-purpose turned tolerance is a few thou, a feeler gauge set steps in thou, and paint film thickness and plastic sheeting are specified in them.
Watch out: The same length is called a mil in the wire, plastics and coatings trades, which collides badly with the angular mil of artillery and with the millimetre. "Twenty mil" of polyethylene is 0.5 mm; "twenty mil" on a gun sight is an angle. This site keeps the machinist's name to avoid the ambiguity.
| 1 thou | 0.0000254 m |
Solvers that use length