...did you consider adding a second z-axis to the MM Y-car. It is designed to hold a second spider and slide. See below link for 2 z's in the car.

http://www.mechmate.com/forums/showt...7&postcount=54

Sean...
I am not looking to develop (or sell) any of these drills. I have noticed that Mike Richards has given a lot to this forum, as he has to me. To "pay some back" to Mike, I was hoping to get the info that I have for CNC controlled drills into the hands of someone with MechMate and Gcode knowledge so that users here could possibly implement them. Hopefully someone will step forward.

I have found that there is no need to add a second Z to add 1 or 2 of these drills. The mass of the dual drill setup is not recommended unless a fairly robust drive system is in place. In SB terms, they will work fine on an alpha, but not a standard. The standard can use the single with no problem. I dont know how those (SB) specs correlate to what MM builders are using.

I installed 2 of these ARO's on my dual Z machine. In the videos you can see I never added the second spindle. Had I known, I would have saved the money for the second Z and used a dual setup on a single Z machine.