Random 3D printing chatter

I needed an extra driver channel on my big CoreXY. I had been using an external driver but it was starting to annoy me having to control it with jumpers and the voltage put rather than the Duet configs.
So, I looked at adding a Duex5 expansion but then decided to get a Duet 3 Mini 5+ with the additional 2 driver addon board. This gives me seven TMC2209 drivers.

Here it is all mounted up. The wire hanging down the middle is for an accelerometer I haven't wired up yet.

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Ordered the FLSUN V400..30 to 40 day delivery otherwise 120 dollar shipping fee. Hoping it works as well as I expect it to. Little worried about PEI bed since I am using PETG, so will see how I get on.
 
Rilot said:
Decided to stick an accelerometer on my extruder carriage to take advantage on input shaping.
The CoreXY is running at 200mm/sec and 10,000mm/sec^2 but I've got a fair bit of ringing I'd like to get rid of.

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Would love to get your insight with input shaping/ringing control, as that is currently why I stick to to low speed for part I make.
 
Scougar said:
Would love to get your insight with input shaping/ringing control, as that is currently why I stick to to low speed for part I make.
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On my system if I go above 30 I get ringing lol. (PETG with 0.6 nozzle). Think adding linear rails actually made it worse. (EDIT: Quoting myself LMAO. I meant to quote @Rilot on his input shaper).
 
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Running Marlin? RRF? Klipper?
Have you done an acceleration test? Ringing is almost certain to be acceleration rather than speed.


The way I tune is the following (this assumes you have already calibrated your steps/mm and all the other basic motion calibrations):

Determine maximum volumetric flow rate of hot end:
  • Heat up to temperature of the material you are testing
  • Extrude 100mm of material at say 4mm/sec - Weigh the extruded amount
  • Extrude 100mm of material at 5mm/sec - Weigh the extruded amount
  • Keep upping it until the extruded amount drops significantly = skipping.
  • Take this figure and put it in to the following equation: t=d/s so time = 100mm/maximum extrusion speed in mm/sec. So, say it's 10mm/sec then it's 100/10 = 10s
  • 100mm of 1.75mm filament is 240mm^3. Divide this by the figure above = 24mm^3/sec. This is your maximum extrusion rate.
  • At 0.2mm layer height and 0.45mm line width, maximum speed is thus: speed = volumetric flow / (extrusion width x layer height) so speed = 24 / (0.45*0.2) = 266mm/sec
Your figures will be very different to those but the methodology should be the same.
Once you have those figures, take an acceleration test piece and slice it so that you are running at 50% of your maximum speed above and varying the acceleration as you print. Start at 200 mm/sec^2 and go up from there.
Examine your test piece for ringing. Where the ringing gets bad enough to be annoying, that is your maximum acceleration.
 
ElliorR said:
Just upgraded my printer to an all metal hotend and today I learned all about PID tuning. I have no idea why it’s taken me this long to get into 3D printing. At the very least I wish I had gotten into it during 2020.
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Just thinking about getting into 3d printing and want to buy a decent machine to make bits for my sailing yacht. I am a print designer so have Illustrator skills and am learning Freecad but am at a loss as to where to start on hardware???
 
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