Would moving from A4988 to TMC2130+ improve/affect print quality?

Title says it all, really. I moved from RAMPS to RADDS, and while I am impressed, I don't notice TOO HUGE an improvement in print quality, although it is definitely there, and I'm assuming that has to do with the fact that I never changed the stepper drivers from the chinese A4988s to anything better, as I'm told that these are probably the worst drivers.

The TMC21XX series definitely looks promising in terms of sound reduction, but I've already dampened my motors, and have the whole printer itself on a damper. Would changing to these drivers improve accuracy and artifacting, as well?

Also, as a side-question, how do I put 24v through them? I plan on solving any accuracy issues with 0.9 deg steppers, but there are pretty much no tutorials on that, I don't even know the first thing about a 24v system.

Edited 1 time(s). Last edit at 03/29/2018 10:31PM by Lobotomy.

RADDS itself is 24V tolerant, you can power the whole controller which feeds the drivers...
But all other components are fed with 24V too, like fans, hotend heaters, bed heater.

Print quality won't be better, maybe you'll even see more overtemp issues than with A4988

Which firmware are you running on RADDS, what type of printer do you have, and what particular print quality issues do you have?

Edited 1 time(s). Last edit at 03/30/2018 02:48PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Running the latest of your build of RRF, Kossel 2020 design, and slicing my prints with Cura. I am more than willing to find a new slicer, if that's my problem. While the prints come out fine for the most part, there are very small outer shell inaccuracies that I wish to make go away. There are very visible layer line discrepancies, vertical line artifacts, and lots of salmonskinning on round surfaces. I am told that TL-Smoothers take care of the latter somewhat, but even if I were to get them, that method sort of feels like cheating in some way.





Like I said, I'm really happy with the mechanical strength and layer adhesion of these prints, and the individual layers themselves look flawless. It's very nice in that regard that, but I know that I can squeeze a bit more dimensional accuracy out of this printer than what I'm currently getting, and I've seen lots of other folks get rid of these artifacts.

One thing I REALLY want to get rid of is this dumb pimple line that forms, every single time I try to do a small cylindrical print. A good example is this failed dummy bullet (failed from poor extrusion):



That vertical line just destroys prints like these, where having a complete, unbroken, circle counts the most.

Edited 6 time(s). Last edit at 03/31/2018 03:11AM by Lobotomy.

Vertical line artefacts on flat surfaces when the layer height is an exact number of full steps may be caused by low-current microstepping issues. These are common when using DRV8825 drivers, but A4988 drivers can suffer from this too. TL smoothers or equivalent (2 pairs of back-to-back diodes in series with each phase) will help with that.

If the vertical lines occur only on curved surfaces, then that's an issue with either the STL model having too low a resolution in the first place (i.e. the plane segments used to approximate a curved surface are too large) or a slicer issue.

The one on the cylinder is a layer change seam. You can choose in the slicer whether to have a seam like that or to randomise the layer change point. Layer change artefacts are difficult to get rid of, but you can experiment with the following:

- printing external perimeters first or last
- pressure advance amount, or coast to end amount in the slicer if you are not using pressure advance
- retraction on layer change

I think you may also have a small amount of Z banding. Are you using PID or bang-bang control of the bed heater?

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
Vertical line artefacts on flat surfaces when the layer height is an exact number of full steps may be caused by low-current microstepping issues. These are common when using DRV8825 drivers, but A4988 drivers can suffer from this too. TL smoothers or equivalent (2 pairs of back-to-back diodes in series with each phase) will help with that.

Cool, I'll pick some up.

Quote
dc42
If the vertical lines occur only on curved surfaces, then that's an issue with either the STL model having too low a resolution in the first place (i.e. the plane segments used to approximate a curved surface are too large) or a slicer issue.

The one on the cylinder is a layer change seam. You can choose in the slicer whether to have a seam like that or to randomise the layer change point. Layer change artefacts are difficult to get rid of, but you can experiment with the following:

- printing external perimeters first or last
- pressure advance amount, or coast to end amount in the slicer if you are not using pressure advance
- retraction on layer change

Is there a feature-rich slicer that you'd personally recommend? I'm using Cura 3.2.1.

Quote
dc42
I think you may also have a small amount of Z banding. Are you using PID or bang-bang control of the bed heater?

Not sure, how would I find that out? Anything in here?

; Heaters
M305 P0 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S100 ; Set temperature limit for heater 0 to 100C
M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1
M143 H1 S300 ; Set temperature limit for heater 1 to 300C
M570 H1 P30 T10 S120 ; Give more time to heat up
M302 P1 ; Allows for Cold Extrusion

; Tools
M563 P0 D0 H1 ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C
;M563 S1 ; Allows for tool nomenclature compatibility between Slic3r and RepRap (Tools 0&1 vs Tools 1&2)

Also, while this probably isn't the forum to ask, what do you feel about Golden Ratio Layer Height?

Edited 1 time(s). Last edit at 04/02/2018 05:12PM by Lobotomy.

Slicers: I haven't used recent versions of enough of them recently to give a recommendation. For a long time I have been using S3D because a couple of years ago slic3r and Cura had serious bugs. But Cura has improved a lot recently so I am trying it, and I hear that slic3r has improved too.

Heater control: assuming you are using recent firmware then it's the M307 commands that define whether PID orcbsng-bsng is used. Send M307 H1 to check.

Golden ratio (or other irrational ratios of layer height to full step height): if you have vertical bands on flat surfaces caused by low current microstepping issues on a delta printer, it may help to hide the problem (I've never had that problem so I am relying on what others reported). If you don't, it's probably better to make layer height a multiple of full step height

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

The output didn't tell me whether I was using PID or Bang Bang, but I set it to PID in a new line in my config.g to make sure, as seen below. Do you think I should run M303? I've never tuned PID before.

M307 H1 A340.0 C140 D5.3 B0 S1 V0

I can only imagine that I have a lot of cubes to print out, after I get TL-smoothers.

Edited 1 time(s). Last edit at 04/03/2018 02:36AM by Lobotomy.

I recommend you run M303 on each of your heaters. Otherwise you are more likely to get heater faults, because the firmware will assume that your heaters behave according to the default heater models.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I would doublecheck if it isn´t partly due to the slicer, and would try out KiSSlicer which I found to be pretty good.