Hi Jim, 

i have used 'mechanical mixing' in my builds with no particular issue.  like anything, some practice to get your set up and technique down is important.

i do agree that it tends to introduce more bubbles into the mix, but again, that is where technique comes in.  i quickly learned to submerge my paddles in the mix before starting the motor to avoid beating the surface of the mix as well as stopping the motor with the paddles submerged as well.  obviously, accidentally pulling wet moving paddles out of the mix can throw a lot of epoxy around and make a mess quick.

in general i found myelf working with larger red solo cups only half full to minimize spillage and the risks associated with fast moving equipment.  basically, you have no margin for any mistakes if you are mixing a full cup.

i also work with pre-warmed epoxy so that it is thin and wets out and pops any bubbles quickly.  i would not mechanically mix cold epoxy.   timing is also critical.  mechanical mixing can be very effective setting off the epoxy perhaps a bit faster than a manual mix.

i think the biggest issue with 130 square feet is managing it down to a number of small batches that can be controlled.  a mechanical mixer properly set up can reduce the fatigue of that much hand mixing.

h

   Thank you! That is exactly what I wanted to hear, and thanks for reminding me about warm epoxy, it's been over a year since I've worked with epoxy. Thanks again jim