Octoprint instead of display for better performance?

Hi,

Im looking for ways to help my ramps stop stuttering on round/highly segmented parts. As we know ramps for deltas are not ideal because of its limited processing speeds. However it seems that some people have absolutely no problems and artifacts and other like me have them.

I recently experimented with a Duet 0.6 but for various reasons I had to adbandon it. Until the Re-ARM comes out I dont want to spend Smoothieboard money.

Some things I was considering to help with the stuttering.
+++ While I was playing with the Duet I learned about the "hardware flowcontrol" option, so I will be testing if that makes a difference with the ramps as well.

+++ I turned down the segments per seconds however I didnt have the feeling that it changed anything. I tested even with 10 segments/s and did didnt even slow down the print.

+++ I removed the display. For some bloggers this seems to be the biggest eater of processing power, however untethered printing is quite handy, so I was thinking if installing Octoprint will help here.

My question is if someone ever compared performance with and without display and if Octoprint as a host runs the whole print smoother.

Cheers

People with graphic displays suffer the most with ramps/delta config. Reducing segments/sec would be my suggestion too, but if it still doesn't change behavior, Pronterface would work as display. Octopi is another interesting way, if you want to go wireless.

Edited 1 time(s). Last edit at 11/20/2016 01:34PM by o_lampe.

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sungod3k
I recently experimented with a Duet 0.6 but for various reasons I had to adbandon it.

Why did you abandon it? There are lot of people running deltas very successfully with Duet, and it's easier to set up than Octoprint. RepRapFirmware is the only firmware that doesn't use delta segmentation at all. To quote an OEM that has recently switched to Duet for their deltas, "We only use quality materials for the printers so we know the printquality is there too. Duet is sure the best board we tried (and we have tried around 11 boards)". See [www.duet3d.com].

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sungod3k
+++ While I was playing with the Duet I learned about the "hardware flowcontrol" option, so I will be testing if that makes a difference with the ramps as well.

It can't be used with RAMPS, because RAMPS has a USB-over serial connection without flow control, instead of native USB.

---

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].

@Olampe: with pronterface as display you mean normal usb connected operatIon?

@DC42: Im sure DuetWifi works a lot better than 0.6, but after the whole M109 (2 times it actually stopped during the print and I had to "force next") issue from my last post there were other things like the thermistor not responding sometimes, G32 not giving my a correctly adjusted plane and the allegros instead of DVRs. I had a print job the next day so I went back ramps. If I continue Duet 0.6 and give it another shot in the future I need a wifi interface anyway, so octo print can be used for both.

Edited 1 time(s). Last edit at 11/20/2016 03:42PM by sungod3k.

Are you using Marlin or Repetier?

For what it's worth, I've had no problems with stuttering when using a 4 line LCD display (on two delta printers). Certainly up to the speeds that I print at (~30 - 50 mm/s).

I have a raspberry pi that I bought to use Octoprint with, but tbh I find it easier to use the LCD panel and stick an SD card in there. My computer is in a different room to the printer, and I like to control the start of the print while watching the printer do its thing. The pi is now just a glorified webcam.

@nebbian: interesting, I print 80mms usually but speeds doesnt seem to make a difference, at least in the test I did some time ago.
Are you using 16th or 32th stepping? now that I think about that I should try to test the stepper dampeners that I bought and maybe go back to 16th step free some procession capacity.

As for Octo vs display, true the display is simpler but if removing it really helps with the stuttering its worth it.

No shuttering with Repetier on RAMPS.
No LCD, segments per second (SPS) set to 90. 1/16 micro stepping. Typical print speed 120 mm/s.

Shuttering does not depend much on the print speed. It depends more on your SPS setting. The most expensive computation is squre roots. And the number of square roots computed per seconds depends on SPS. The next in line is computing how steppers are incremented and this depends on the speed and micro-stepping. So you may try less aggressive micro stepping.

SPS has impact on head position error due to segmentation. The smaller the SPS, the bigger the error. The bigger the printing speed the bigger the error.

If you print at 80 mm/s then you can go with SPS down to about 50 and head position error should be around 1 micro step.

@sungod, I'm using 1/32 on both printers, one uses 1.8 degree steppers, the other uses 0.9 degree steppers.

I think that Hercek is on the money with regard to segments per second, i think I dropped my SPS to 120 or so after some issues at the start.

Hi,

If you use Marlin, you need to check the last RCBugFix. They have put a patch for LCD and stuttering. To resume: When marlin see round/highly segmented parts, it stop to refresh the LCD, you need to activate it on configuration_adv

Github patch on Marlin repo

I use it now, and the patch working wonderfully.

Edited 1 time(s). Last edit at 11/23/2016 09:02AM by zelogik.

That is an awesome feature. Thanks for the tip.

And as I haven't said my hardware:

Ramps + arduino 2560 + REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER with marlin RCBugFix (21-11-2016).

Speed print at 60mm/s (and often FR to 150%) BUT it's on a tantillus (simple x/y cinematic) and not a Delta.

Hope that helped you!

Full graphic control on a delta is your main problem. If you need the display, I would invest in a simple display rather than the full graphic display, though in my case I just disabled the display in the firmware and used the unit for the SD card slot. Printing from the SD card rather than over USB should also help...even if you do set-up Octoprint which essentially just replaces your computer for controlling prints.

I am loving my Duet 0.8.5, works great and the Duet Web Control makes a display redundant. Though I have considered recycling an old phone as a wireless display on the printer. Not sure why you had issues with the 0.6 other than possibly just being a cheap Chinese knock-off. Unless you already returned it, you might try giving it one more attempt. Otherwise I believe their are some smoothie board clones available in the $50 price range until you can get something better.

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Though I have considered recycling an old phone as a wireless display on the printer.

Try to find a Win8.1 tablet with 7" or 8" display. They can also be used as slicer etc...
I got mine for 50€