RE: [CAD_CAM_EDM_DRO] Measurements to compare machines

I am not certain I agree with you on the flex of the Sherline mount. The pin is simply pulling the head in against the mount and the very large square key on one side actually makes a very solid mount. I'd bet the TAIG headstock actually flexes more. I say this because I loaned a friend my TAIG headstock so he could make a grinding head with it. The flex was too great to make a decent grinder.

But that is just an opinion not backed up by a measurement or two although my friend did employ an electronic balancing system to measure the vibration on the TAIG setup.

I purchased a Sherline mount adapter from you for my TAIG mill. I didn't pay much attention to it other than it works very well. For the Pin, did you use a strong steel like 4130 and stress relieve it or Stressproof for the pin? 

The Sherline mill would greatly benefit from an additional support for the bare 12L14 ways that the Z-axis head travels on.

If you go to the TAIG group, you can read about the improvements I've made to the TAIG mill. They seem to work very well although I haven't used it in any production capacity.