I have finally finished building the mechanical platform. I was missing 9 T-slot nuts from my kit, and ATI sent the missing parts right away. In the mean time the rest of the electronics came in, one package at a time, it was like christmas every day! Tomorrow I should get the filament, but I'm a few days away from needing it.
Having the .stp file opened in a viewer while building was IMMENSELY helpful, even better than the best helicopter kit manual. I used the online viewer at
MyCadBox to check my progress. The drawing doesn't exactly match the ATI kit however, but it's fairly straightforward. I do have two spare M5x6 bolts in the end, not sure what I forgot, as all T-slot nuts are installed. We'll find out soon enough...

There is some backlash in the current delrin belt clamps, I had to insert some cardboard in the flat side of the clamp to squeeze the belt more tightly and eliminate any backlash. The latest kits have GT2 belts and pulleys, and they are already the correct length (closed belt loops). There is some slight rubbing of the belts on the carriage and build platform, but I don't think it will be a problem. According to the cad drawing the belt is supposed to be right up against the moving platform/carriage.
I am having a hard time making sure everything is squared, especially the Y axis, because it is loosely mounted on the extrusion, and the OrdBOT cannot easily be flipped over to help squaring. I guess I'll just do my best and adjust from there if necessary. Also, setting the Y axis at 90mm (as per the drawing) means I don't quite cover all of the build platform; I'll probably have to put the Y axis at 100mm or 110mm to get the full build extents.
I have no way to mount my EZStruder to the carriage, hopefully I can cobble something together with zipties and wood blocks long enough to print a proper support for it.
I have programmed my Azteeg X5 (so much easier than Arduino-based platforms!), now it is time to wire everything. I don't plan on hiding the wires, as this will make modifications too hard in the future. To be continued...

- Belt rubs