Robert E. Nee published a new build:

Read more about this build...

 

Thank you for your kind words, however, I wanted to be more scientific in the motor selection than I actually achieved. For instance, I could not obtain the strepper spec sheets for pull-out torque versus stepping rate for either my nema-17 or nema-23 motors. I defaulted to using nema-23 motors. Also, my efforts at heat plate simulation were disappointing as Matlab provided several different methods and their results did not agree. I had a preconceived view of what the results should look like when radiation is enabled and it turns out aluminum emisstivity has two values depending on whether the aluminum is anodized or not. My aluminum plate is non-anodized with emiss = 0.08 versus emiss = 0.85 for anodized aluminum. With such a low value of emmisity, radiation is effectively disabled whether the simulation switch is on or off. I ran simulations later with emiss = 0.85 and as expected the plate temperature plateaued much quicker. Your referenced links are helpful. I rushed into my build and ended up reworking much. My gantry design suffers from the fact that everything must be moved to move the printhead. I did not want to raise and lower or move the heat plate. I would have more confidence for a much smaller effort but I already have 2 3d printers of "normal" size.
Good luck with your builds,
Robert E. Nee