The brown truck just arrived with my Hadron kit. It looks good. I haven't checked each item against the BOM (kindly provided with the kit), but I did check a few things I had wondered about.
The Z nut now has a steel nut embedded in the polymer nut block (see posts earlier in this thread). The steel nut rides on the threaded rod with less resistance, but more backlash than the Delrin threads. I don't think the backlash should be an issue if the controller always drives the Z axis up as the part is being built, and the lower thread resistance should result in more repeatable Z axis motion. I'd imagine for small movements, when there is thread binding friction, it might jump more or less for each small commanded motion for a new layer, resulting in more error in Z axis layer height with the Delrin threads? Regardless, I greatly appreciate not having to make the Z nuts like I was forced to do for my first Hadron when no kit was available.
I was a bit concerned about the quality of the threaded rods for the Z axis. I bought the last pair from Misumi. They weren't cheap, but they were very high quality. The threaded rods that came with the kit also seem to be very high quality. I didn't put them on a surface plate, but they seemed very straight and true when I rolled them across a tabletop. With good alignment at the shaft coupler to the stepper motors, I wouldn't expect any significant wobble from the Z axis motion, particularly with the new Z nuts. Any looseness of the new Z nuts in the XY plane, shouldn't matter, because the ORD Bot structure is well constrained in the XY direction. In fact, looseness in the Z nuts should help prevent wobble in the XY plane by not pulling the frame slightly out of position. It should be better to have the frame constrained and the Z axis floating a bit in the XY plane and only imparting Z axis motion. The proof will be in the pudding, just as soon as someone builds one of these kits and starts printing.
The stepper motors look good too. I did an online search for the part number from the label on the motor, KL17H247-168-4A, and it took me right back to Automation Technologies.
http://www.automationtechnologiesinc.co ... pper-motorThe motor seems to be used for many 3D printers, and is also a Keling part number. It's a 62 ounce-inch motor, which should do very well in this application.
I was a bit surprised at the size of the box with the fasteners and small hardware. There are a lot of baggies! Again, without a kit, I made minimum purchases of 100 of most of these fasteners for my first Hadron build, which is the dumb way to do that. Oh well, I guess it's good to have spare parts. It's great to get a kit, and I'd highly advise going that route if possible. It'd be great if Automation Technologies could eventually have kits on the shelf and ready to go.