Iverntech NEMA 17 Stepper Motor with Integrated 310mm T8 Lead Screw for Prusa i3, Reprap Corexy, MP Select Mini 3D Printers and CNC Mile Routers

These work very, very well; very smooth, straight, and powerful. My machine uses 2 Z-steppers, so I had to increase the max. current on the driver, and add a heatsink. A note to Repetier users: The leadscrew calculator lists a T8-2 leadscrew, but the value this calculator returns must be divided by 4, for example, the motors are a 1.8 degree step, and my driver is set for 1/16 step, giving 3200 pulses per revolution. On these 4-lead screws, 1 revolution gives 8mm of travel, so the correct Z-step setting is 400 pulses per mm. Hope this helps.

My unit lasted all of about 300 seconds of total operating time before seizing up. The load was all of 2 ounces, requiring 6 inches of travel. Worked fine the first day as I was assembling and testing. Then, coming back 3 days later to use it was totally locked up. I swapped in another NEMA17 stepper and that worked perfect, so my controls and electrical are all fine. I tried working the motor by hand once disconnected and, at first, it wouldn't rotate at all, Eventually, it began to rotate but slowly and with serious resistance. Extremely disappointed. UPDATE: After reading my review, the manufacturer has responded directly and immediately and have been working with me to understand my use case. They have stepped up and are shipping me a replacement unit. This is excellent customer support and I look forward to a working unit.

Will they work on a Voron Trident? Yes, but..... you might have to tweak your rotational distance a little. And be prepared for the bed to drop when the steppers are released. I got around the droop by sending my bed to max Z at the end of a print. That means the motors will initially stale during the next home but it works. I would have returned these if I had completed my printer build on time. Unfortunately I was outside the return window when I finally gave the printer it's first G28

Came well packaged in a cardboard box and foam. Installed really easily on my custom printer and was a perfect fit. It did come with a slight bend near the top of the leadscrew but my rigid Z axis counters any flex. Makes for a vary rigid Z axis with no detectable slop or backlash.

Very well packaged in protective foam box. Rod was straight and unbent with a good thread.