How to use a trammel head
as a marking gauge?

Step 1 – Install pencil in trammel head

Install a pencil or other scribing device in the body of the trammel head.

Step 2 – Clamp trammel head onto engineer’s square or try square

Clamp the trammel head onto the blade of the square a set distance from the edge of its stock.

Step 3 – Run square along edge

Position the square on the edge of the workpiece.

Run it along the edge of the surface you will be marking, so that the pencil installed in the trammel head marks a line down the length of the part.