My idea sketch is attached. Red hatched bit slides, blue hatched bit is the holder.

Some issues I can think of (in no particular order)-
*)If going for the full ATC route, due to the spring travel needed, a small air cylinder might not be able to provide enough force to release the holder. Could be solved by using a larger diameter, however at what point does diameter become an issue? Alternative, although more bulky option would be an external cylinder with lever mechanism (this would eliminate issue of needing rotating air seals)
*) Lots of bits would need hardened, ground and polished.


Attachment 6954



i2i, if you've got a spindle with a drawbar, there are plenty of ATC options about. Having a hole through the spindle opens up lots of options.