Prusa upgraded to duet, weird extrusion

[JamesM]

The pauses you speak of are most likely due to the jerk setting you have for your z-axis and extruder. If you are using pressure advance I would change the extruder instantaneous speed change (jerk) to something around 2000 and the Z somewhere in the 150-300 range.

[Murloc992]

@Phaedrux said in Prusa upgraded to duet, weird extrusion:

@Murloc992 said in Prusa upgraded to duet, weird extrusion:

M566 X600.00 Y600.00 Z12.00 E150.00 ; set maximum instantaneous speed changes (mm/min)
M203 X9000.00 Y9000.00 Z360.00 E7200.00 ; set maximum speeds (mm/min)
M201 X1000.00 Y1000.00 Z200.00 E10000.00 ; set accelerations (mm/s^2)

Yes your Z and E axis settings are very conservative. this will make for slow retractions and layer changes / zhops.

The low XY jerk and acceleration don't seem to match up with the large amount of ringing you are seeing. Are your belts a little loose?

Here's what I use on my i3

M566 X800 Y800 Z60 E3000 P1				; Set maximum instantaneous speed changes (mm/min)
M203 X12000 Y12000 Z900 E6000				; Set maximum speeds (mm/min)
M201 X6000 Y6000 Z200 E5000				; Set accelerations (mm/s^2)
M204 P600 T3000						; Set accelerations (mm/s^2) for print and travel moves

I will try your settings. My belts are not loose, just the right tension, printer moves more smoothly and silently with these motors I put on. Hopefully it's just a setting issue.

I will take a video of it printing in the evening.

No other variables except for the motors have changed.

[Murloc992]

@Phaedrux

So I used your settings, prints look identical, just that it printed WAY faster. Weird..

I just noticed that my X idler might be bigger than Y one.. I will investigate shortly..

[Murloc992]

Nope, seems identical. I am out of what I can do. Every axis seems to move extremely smoothly and fast. The frame is as rigid as it gets..

[T3P3Tony]

@Murloc992 if you are still seeing the weird pulsing with @Phaedrux 's config then it might be worth swapping that motor with one of the other ones you bought to confirm that the problem is not with the motor.

Another bit of elimination is to try using E1 for the extruder to rule out some weird failure mode of the driver (highly unlikely but you never know). You can use M584 to switch between E0 and E1

[Murloc992]

@T3P3Tony I already tried switching the motor, same pulsing. I haven't tried switching the driver yet, but I use dual Z, can I set Z as E0?

[T3P3Tony]

@Murloc992 yes remap as you like. Also another option for this test you can connect two Z in series to the Z motor connector

[Murloc992]

@T3P3Tony I am printing another single wall cube and notice something new with new acceleration/jerk settings. I will post soon. I still hear the pulsing though, but it looks a bit different than before.

[Murloc992]

X Axis:

Y Axis:

As you can see, increasing the settings(speeds, acceleration) made the pattern reversed(of all the things) and more intense.

[T3P3Tony]

@Murloc992 what about rotation by 45degrees?

[Murloc992]

@T3P3Tony

Let me try.

[Murloc992]

Original cube on the left, the 45 degree rotated on the right:

[Phaedrux]

It's gotta be the new extruder motor. Perhaps it came bad from E3D?

[Murloc992]

@Phaedrux

I tried the X and Y motors instead of it, all the same..

[Murloc992]

Could it be belts? I changed mine to spring steel mesh belts(because I didn't have any others), I will buy proper (normal) gt2 belts tomorrow.

But I think with belts I would have perimeter patterns, matching the tooth spacing..

[Phaedrux]

@Murloc992 said in Prusa upgraded to duet, weird extrusion:

spring steel mesh belts

That might explain the excessive ringing shown on the other models, but I don't think it explains the diagonal pattern on the cubes.

[Murloc992]

@Phaedrux

The primeter walls seem to be perfect when looked from above though.

Now that I zoomed the picture in, it seems microscopically blobby..?

[Phaedrux]

Were you able to test a different driver yet?

[Murloc992]

@Phaedrux

I will right now.

[Murloc992]

Same..

The light is non uniform but all of them look semi identical.

Left to right: the original one, 45 degree, 45 degree + swapped driver

I made a video while printing this one:

Raise your volume a lot to hear the pulsing:
https://www.youtube.com/watch?v=wpG9eKp1ytA

I know it's not the bondtech gear or the shaft for sure, as it is spinning slowly and pulsing dozens of times per rotation. Same was with the other motors.