How thick are response pads?

I’m taking a machine shop class and I’m making my own Yoyo as a project, but I don’t know how deep to cut the groove for response pads does anyone know?

There are lots of different sizes. Look at different pads they sell here at yoyo expert.

Normal yyf 19mm OD CBC response pads are about 1.1/1.2 mm

I highly suggest a pair of digital calipers. They make figuring things out way easier.