My printer is exhibiting Z-axis banding and I’m looking into anti-backlash nuts to eliminate it. However, I don’t know which one would be better, one of the brass nut + spring solutions or the delrin anti-backlash nut on Openbuilds.
The printer is built using Openbuilds V-slot, so the delrin one would be a no-brainer to mount ( I’m currently using one of their delrin nut on each Z motor), but I’m not sure about the effectiveness of their solution.
Has anybody used either one of these anti-backlash nuts?
They both work on the same basic preload principle, but the brass one will self adjust for wear over time and the delrin one allow for adjustable amounts of preload (you could adjust the preload on the brass nut too, but you’d have to change out the spring each time).
Either choice should give you the same effective anti-backlash effect, so I’d go with the one you’ve got mounting for already.
That said, z-banding can be caused by many things outside of just backlash, so you may find that these nuts aren’t a magic pill. You should check the math on your screw pitch and layer height size to make sure there’s no periodic error there, calibrate your extrusion and check your hot end PID calibration, and if you have a high powered heated bed (like a high wattage silicone heater, or definitely a relay driven AC silicone heater) make sure you’re using PID temperature control on it and calibrate your PID for that as well.
I’ve used the brass one. The oil-impregnated brass are nice, but plain brass get really noisy w/o grease or frequent oil. We use delrin that is slightly under-tapped if that makes sense.
Z banding is usually a result from a hard coupling between the Z nut and the X/Y plane. These threaded rods are never a 100% straight and aligned. So they are introducing X/Y motions as they rotate.
This nut is most likely just going to be an expensive upgrade without results. As the weight of whatever you have on your current nut already pushes the backlash into a single end.
