After I got the kids to bed, I decided to spend a few hours eating glass, I mean standing in front of the lathe. I made a quick sketch of how I thought the spindle was supposed to work based on what I've learned from pictures on the web. Then I dove right in.
My Harbor Freight 7x10 can only handle short pieces of 1.5" aluminum, so I had to make the housing shorter than I would have hoped, but we'll just have to see how this prototype works out. I got the housing, spindle, and gripper finished tonight, and it is quite late, so I'm going to bed.
Here you can see the gripper and how I machined it to fit the 15 degree taper of the spindle. This small part will close down on a ball on top of the tool holder and the drawbar will pull this up into the taper.
Found some bearings at BCS for $2 per pound. Luckily there were two that were the same.
The tool-end of the spindle. The gripper still needs some machine work so that it fits down inside the spindle and there is room for the tool holder. I left it large so I could think about how it was going to work before I cut it too small.
A couple of shots of the 15 degree taper of the spindle bore. That cold rolled steel doesn't machine all that well and leaves some galling. I'm going to get some nice steel for the production model once I determine if this is going to work.
Slightly different angle showing how the gripper goes into the spindle bore.