Speed limit / Speed limitation with Klipper

General Discussion
1

With speed inthe slicer setup at 120mm/s or even at 200mm/s, my actual print speed never exceed 80-90mm/s…
What am I doing wrong?

Here is the part of my printer.cfg related to speed…

[printer]
kinematics: corexy
max_velocity: 300
max_accel: 2500
max_z_velocity: 5
max_z_accel: 50
2

I have a similar problem Except that my speed limit seems to be right at 250 mm a second regardless of what the display says or what I put in.

3
  • These settings are the machine’s default velocity and acceleration
  • They can be overwritten by a set_velocity_limit or M220 / M204 command
  • Depending on the used slicer these mechanisms may be handled slightly different

→ Check the limits and settings in your slicer and adapt accordingly. Finally, check the resulting gcode and its velocity and acceleration parameters

1 Like
4

Gcode is asking for a feed of 30000
PrusaSlicer called for 500mm/s
With fluidd Is reading 500mm/s The printer never physically goes faster than 250mm/s
If I increase the speed 200% there is no change to the printer and the display reads 1000mm/s.

My max velocity is set to 5000, acceleration to 8000mm/s^2
Square corner velocity is 5 and acc/decel at 4000. I’m printing a big circle though so it should be just velocity.
Acceleration control is off in the sclicer.
I hope this makes sense to someone…

Add on. I’m using an SKR2 with 2209s and Raspberry Pi 4

5

A circle is about the worst thing you can choose when trying to evaluate these topics. You should definitely familiarize yourself with how acceleration, velocity and gcode work on a 3D printer. There are more than enough tutorials out there.

You are simply hitting the physical limits of what your printer is able to do with respect to the requested distances and motion parameters.

6

No. it’s not the limit. when I run normal prints I run a travel velocity of 1500MM/S which moves the head about 10 times faster than the print speed that I run at 150-180mm/s and i just reduced my acceleration from 10k to 8k due to noise. , also I’m an ex physics teacher, I’ve got a pretty good understanding of acceleration and such things. My coding kung fu is weak…

7

P.S. I’m doing this inside of a 100deg C chamber printing Gizmodorks Polycarbonate.

8

Sorry, but at this point I will stay out of this discussion from now on.

2 Likes
9

You are completely right.

On PrusaSlicer, in “Printer settings” (tab 4) and “Machine limits” I increased the limits, but with no results changed.

Looking for M220/M204 commands I found M204 on the gcode file. But inside “Print settings” (tab 2) and “Velocity” I found the value that are reducing my limits.

Thanks a lot man, I’m going crazy trying to understand what is happening!

10

Give it another try to Sineos explanation, because he is not questioning your knowledge. He is telling you what the problem is and not where the solution literally is.

Something that you should check before indicating that “as a physics teacher you understand accelerations and suchs things”, because it seems that you are not understanding that there may be more limitations than what you have found, as I has been in my case.

Thanks to Klipper I confirm that my accelerations are reduced “without any expected reason” because I disable it, but I found it in another place where I don’t expected to found it.

There’s no need to be so rude to someone who’s trying to help you.