I'm really wishing I could do automatic tool changes. Currently it's a knee mill with only about 7" of Z travel and a kwik switch spindle.

Does anyone have any good plans for doing something like this? I figured I would have to use a different tool holder type (maybe custom). I have a few unused M-code relays and I was thinking this would be a fun project.

An R8 seems easy to automate as far as mounting since it could be held in place then tightened by a motor. The biggest problem there is that R8's are long so it would only cause more room issues. Maybe a turret on 45 degree's that is physically connected to the mill head (possibly using a modified Kwik Switch so that it could be reverted back easily)

I figured I could possibly motorize the knee to gain more room for the tool changer. I'm not really sure how precise these are to end up in the same place each time though (back-lash shouldn't really be an issue given that gravity is always pulling in the same direction). This would require another Axis though - it's not in my budget to swap my CNC controller right now.

Any clever ideas for this?