Intermittent Z issues
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M350 X16 Y16 Z64 E16 I1 ; configure microstepping with interpolation
duet wifi only support interpolation at x16, so your config does not work.
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to me i looks like z banding.
have you greased your leadscrews? -
@Veti Yeah I know it looks like banding due to the lead screws, but how does that make sense when some parts or half a print comes out perfect? Also I greased my lead screws last month with ptfe grease and they are very low friction, can be back-driven easily. Also the pitch doesn't match the banding, the lead screws are 2mm pitch with 4 starts but the banding is not a multiple of that and changes between prints or sections of the print.
I didn't realize about the interpolation, I'll try changing it and see what happens.
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did you check if the leadscrews are straight?
by rolling them on a flat surface like a glass table.
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Have you PID tuned your bed heater yet?
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@Phaedrux Yes but I'm sure you noticed it is in bang-bang mode. I have an issue where the entire thing hums audibly so I can't use pwm.
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@Veti I just checked the lead screws and there is very slight bend, like 0.5mm off the table. I don't think that would account for what I am seeing here. When I do get a good print, I think I can see the effect of that bend and its is not ridges, just very slight deformation every 4mm. The ridges in the above parts are usually 1.4mm apart but as you can see in the first part on the left, the ridges can be further apart.
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@Phantom329 said in Intermittent Z issues:
the entire thing hums audibly so I can't use pwm.
Try a different PWM frequency? I would say bang bang is your issue. Try a print with the bed is off. To get good bed adhesion try a high temp for the first layer and then 0 after that to keep the bed off. I bet you'll see the banding gone.
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@Phaedrux genius
Bed at 60C for the first layer, then off. I just have to get PID mode working then.
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You can change the frequency with M950 Q I believe.
What kind of bed heater is it?
