Marlin Frimware Issue

So I just downloaded the marlin firmware, been using repetier firmware for a while but I wanted to try marlin to see if it was different.

I setup the configuration.h file for deltas, then I uploaded it to the ramps 1.4 / Mega 2560 that I have, and seemed to work fine until I tried to move in the x/y directions.

Delta segments are set to 200, and no matter what any movement in the x/y even if just straight I get serious stuttering, basically like a choo choo train....

I've looked online and other than decreasing the segment size I haven't been able to find an answer?

How many steps/mm on your XYZ steppers? Also, do you have a graphic LCD connected? If so, I'd suggest disable it in firmware and try again, or replace it with a 4 line LCD2004 which is less taxing. In my experience Repetier is smoother with Deltas than Marlin and the printer can be calibrated more easily (Marlin has a weird and in my experience not so logical way of handling tower angular offsets).

Well...

My Delta with Marlin has deltasegments set to 120 - don't see any issue. - But depends on if you connect a LCD, and wchich one (2004 or graphical)
do not set xyjerk for too low - tried this once, had stuttering.

@ 200steps/mm. are you using 0,9° Steppers? - else I would assume it to high for normal Delta.

The latest marlin rcbugfix version has a mode you can set which limits updates to graphical lcds to reduce stuttering. However main branch marlin is a poor firmware for deltas. There are far too few parameters you can enter to hone your calibration and those you can enter are not very commonly used.

"Downgrade" to Rich Cattels master or testing branch and you will see a big improvement including autocalibration.

None of these comes close to reprap firmware on duet boards for deltas.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Agreed re RRF on Duet, but that's a whole different class and price point. Is testing much better than the rcbugfix branch? I tried Rich Cattell's branch at some point but that firmware has not been updated for so long that it almost seems wrong to use it, the autocalibration worked pretty well though.

With regular Marlin (RCbugfix) I can't set tower offsets in degrees, which makes no sense to me and I never got the bed compensation to work well. Repetier works much better in those respects, with dc42's least-squares calculator on escher3d I can get it pretty well calibrated so for 8 bit boards that would be my firmware of choice.

I have since gone back to repetier, Idid notice in their configuration that its a very low number for line segments for ramps, I don't have an lcd controller, but even going lower on the line segments I still got stutter so I had no idea what was going on. Repetier seems to work fine, and I figured out how to get autoleveling working with repetier, I have magnets that screw up my conductive sensor, but with bed bending correction I am able to account for that, interesting enough. It might not be the magnets at all though since I can get the bed bending to work.

In other words I gave up on Marlin, I was just trying to try a new setup, but from your guys's comments and google searching deltas just don't work very well with marlin it seems... at least with my ramps setup.

I'm using Marlin RC6 on a Delta since about 18 month, and it makes really beautiful prints. Better than my prusa-clone
I do not Need Autocalibration. Just built the Printer as perfect as I could.

I had no luck with RC7 & RC8 - were really worse. RCBugFix was better when I last tested it in December 2016. - But still not as good as RC6. If I think of this thread today evening, I'll upload my config.h

I don't think it's wrong to use rich Cattels marlin, it works. And it has grid levelling and had it 2 years ago. What they've added to marlin since is not fundamental to 3d printing its just peripheral add ons. To be honest the marlin team are nice enough but it's difficult not to use most other firmware and conclude its better.

I've not used repetier but it sounds much better than current marlin for deltas, if you're sticking with 8bit.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

RC's branch just *feels* wrong (to me) because it was forked so long ago and there have been so many bugfixes in Marlin since then...but it definitely isn't wrong to use it, moreso if it works well for you! For Delta's at least I wholeheartedly agree that almost any firmware would work better than Marlin RC(bugfix).

I think what many people do is use rich Cattels to autocalibrate and get parameters then stick them in repetier.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions