A centre marker is an effective tool for finding the centre of a timber workpiece. It is used in a similar way to the centre square, but the steel blade that runs diagonally across the tool marks the work so the user does not need to use a pencil or scriber. The centre marker can be used on square, not just cylindrical stock.
To use, simply place the workpiece in between the arms of the tool and tap the face of the work with a mallet. Then rotate the workpiece and tap again. The blade will have made two diagonal lines. Like with the centre square, the centre of the workpiece will be the point at which the two lines intersect.
If you have access to a milling machine or a drill press, there are a couple of other devices that can be mounted onto the spindle and used to find the centre of parts.
Centre finder set
A centre finder set consists of four probes which are used to find centres, edges or indicate features (see What is a centre finder set?)
Whilst a centre square can be used to find the centre at the edge of a part, a round bar centre finder allows you to accurately find the centre of the middle of a part. To use, insert the shank of the tool into a drill press. When both the legs of the Y are resting on the bar stock and the two points line up, the drill press chuck is directly over the centre of the stock.
