Spindle probes for centering

I worked for a company a few years ago that used spring loaded probes that could be placed in the spindle. They would "kick off" when the edge of the probe was touched on the work surface, be it fixture, work piece etc.

It was perfect for setting up work offsets (G10s) and I imagine a damn sight cheaper than purchasing a light probe of some kind.

Trouble is I cannot find anywhere to buy them. I am unsure of their product name so I cannot find anything online. They come in different types from ball, needle, long, short.

Failing that I am interested in what others are using, obviously in the milling field.

Edge finder?

search ebay "centre finder"

i use a camera mounted at the side of my spindle with an offset vb script to place the spindle where the camera was

Thanks guys, exactly what I was looking for.

There is also this for a more diy way:

http://youtu.be/KOXY4O0UkRM