Circle Tracer

So you could use a compass or a pin, string and pencil to draw circles. In my experience, the compass works pretty well, while the pin, string, and pencil leaves a bit of variability in your circles.

These however, make it very simple to pin the center point down exactly on where you want the circle to be centered on. But the real advantage to these are the the circle sizes. One allows you to draw circles at 10mm in size, 20mm, 30mm, etc, the other lets you draw circles 15mm in size, 25mm, 35mm, etc.

I created this so I could pinpoint the center point of where a washing machine drain hole needs to be in the drain tray, then trace exactly the right size hole that I will then be able to cut.