Have been refining the design of the power draw bar. I'm try to simplify and lower the number of parts as much as possible. I figured the guide rods could be eliminated by strengthening linear actuator. The impact socket will be used to retract the spindle lock instead of the long bolts on the sides.

     The linear actuator will use a 3/8 screw, so i can have many options. (3/8-16, 3/8-24, 3/8-8 acme.3/8-10 acme,  3/8-12 acme).  The over run spring for the actuator has been moved to the screw nut instead at the bottom. This is to make it more rigid and simpler to machine the part, plus removing the guide rod made it a must.

     The spindle lock be two interlocking dogs. In the bottom lock dog the draw bar will be "captured" to eliminate a sticking collet  from driving back and damaging something.

     A 12 point nut and socket will make engagement  more reliable. On my current system system things don't always the first time.

    In theory this is how it will work.

             Step 1  linear actuator moves down. (push out button)
             Step 2  if socket does not engage the spring inside actuator will compensate
             Step 3  slowly turn motor
             Step 4  socket engages nut (switch will verify this)
             Step 5  keep slowly turn motor ( this will turn the spindle)
             Step 6  lock dogs will engage (switch will verify this)
             Step 7 increase motor speed in reverse to loosen
             Step 8 change tool (my job)
             Step 9 increase motor speed forward to tighten (push in button)
             Step 10 move linear actuator up, socket will pull the lock dogs apart.

             Step 11 did miss any steps?

     More changes sure to come.