triangular file

Use a triangular file to mark the cutting line on the stock.

All this is true, but triangular files are nevertheless commonly called "three square".

Small triangular files are also used to sharpen hand saws.

Triangular files have 60 degree angles, whereas "square" is 90 degrees.

Triangular files have three tapering sides.

A knife file is a type of triangular file that looks a lot like a flat file.

Other workers recommend deeply scoring the cannula with a triangular file, then sharply snapping the weakened section.

Three square files, also called triangular files, have a triangular cross-section, which usually gradually tapers.

The next day he purchased a triangular file of approximately the correct dimensions, broke into a smithy whose owner was out of town, and ground it into a similar knife-blade himself.

Orm would construct the knife, then find a way to get the knife into the hands of the man, often commissioning a hilt to suit the victim, but always making the blade from a triangular file so that there would be no trace of where it came from.

It was unusually long, with a wicked point; the cross-guard was minimal, the hilt undecorated, and the blade itself was exactly like a triangular file, except that it was polished to a satin-gleam on all three flat sides, and glinted razor-sharp on all three edges.