Reply to Has anyone here built a diy scratch wheel?

Hi all, while I've been messing around building a midifighter classic, I got to believeing about how to tackle making a scratch wheel.

In the past I've made an arcade spinner from a hard drive motor and a ps2 mouse, the hdd motor had a threaded shaft, that stopped just short of the bottom, I drilled that out, put a long bolt in, cut the encoder wheel off one of the mouse rollers, drilled a small hole same diameter as the bolt and threaded it onto the bolt, held in place with a couple of nuts.

I then mounted the ps2 mouse circuit board to the inside of a tub with the encoder wheel lined up to pass through it, so it works exactly the same as one axis on a mouse. This method worked really well for a spinner for arcade games, very accurate but of course there's no way to sense whether the thing is being touched, only when it's being moved.

I saw another method that does similar things, that deals with touch via capacitive sensing, it essentially uses a metal shaft of some description, with a metal grommet slightly wider than the shaft diameter, with a wire attached to the grommet which goes off to your sensor, on the other end, the shaft is attached to a thin metal disc or you can buy sticky backed copper foil, then a sheet of thin plastic on top.

Has anyone tried anything like this themselves, what kind of results did you get?