Nema34 closed loop tuning on megaprinter??

[Dutchprinting]

Hi Guys,

I have build a incredible big printer (9x6x4 meters)(picture below) with Nema34 motors: Stepper online.
They are all connected to 5x 1HCL expansion boards connected to a 6ch mainboard all running 3.5 beta4

In open-loop mode everything runs fine but because of the weight of the gantry i get some inconsistance in the Y axis.
I want to run in closed loop, this will work (kind of) but i cannot get it tuned properly.

My 'closed-loop-tuning' plugin displays a totally diffrent graph then the documentation examples.
I've tried walking through it multiple times but i cannot get close to a good tuning.
Also tried multiple settings and parameters in het P,I,D,V,A.

But the motors start shaking while moving or ''having trouble'' making steps.
In open loop mode there are no problems except for overshooting at high speeds.
Default settings also give the same problems in closed loop.

The best i could come up with: M569.1 P50.0 T2 S200 C1000 R100 I400 D0.05 V1000 A5000000

CONFIG:
M569.1 P50.0 T2 S200 C1000 R100 ; Configure the 1HCL board
M569.7 P50.0 C"out1" ; control the brake
M569 P50.0 S0 D4 ; physical drive 50.0 goes forwards
M350 X16 Y16 Z16 E16 I0 ; set microstepping

Hoping someone can help!
Kind Regards,

[o_lampe]

@Dutchprinting Hup Holland
If you never tuned closed loop steppers before, it might be a good idea to start with a small setup. Just to play around with the values without risking any damages.

Can't wait to see the first benchy in 1:1 scale

[Dutchprinting]

@o_lampe Haha, Oranje boven!

Yes i was thinking of ordering a small stepper motor, i have one 1HCL and one 6ch mainboard extra so i could test with that. But then still, the forces are so diffrent from a small set up, also the ''belt system'' is not even close to a 'normal' printer. If you have experience, maybe you could come play around with the setup with me, i'm in the great city of Elburg.

I'm hoping @dc42 will chip in, he tested the 1hcl firmware with a Nema34 from stepper-online if i remember correctly.

The 1:1 scale benchy is on my wish list, we need to adjust the model to not be top heavy and suitable for an outboard engine, so we can really sail it.
i think we will break youtube (and a world record) when we do print it.

[o_lampe]

@Dutchprinting said in Nema34 closed loop tuning on megaprinter??:

If you have experience, maybe you could come play around with the setup with me, i'm in the great city of Elburg.

Maybe I do that, I wanted to visit Flevobike in Dronten anyways. Alas, my experience with big printers is marginal and closed loop stepper on RRF even less.
But I often use an anti-racking technology, which is wide spread amongst huge machines.