Machine changes movement speed to faster or slowly on each poweroff/on

Hello, I finished the building and was drawing the crown. However, I observed that the machine presents strange behaviors in some cases. The crown is drawn way bigger (10x maybe). If the machine is turn off, then, sometimes, its movement is slowly but the crown is draw in the correct size i defined in Estlcam.

According to the videos I saw on youtube, It seems that the correct movement is the one that moves the machine faster, but the reason why crown is drawn bigger and why the machine slows down only sometimes, I’m not sure.

Update: I tried moving 100mm in the Y axis and the machine real movement was 250mm (when moving fast)

It is probably an issue with Marlin, but not sure why. Can someone help me?

Sounds like maybe EstlCam speed feedrate is configured with wrong value and/or unit size. I’d double check EstlCam settings with the V1E docs.

Able to share screenshots of EstlCam settings if you don’t figure out?

We still need more details. You built a LR3, using Marlin. Did you use the SKR Pro 1.2, or some other controller? What gcode sender are you using? What do you get from diags on a ‘good’ power on, vs a ‘bad’ power on?

That doesn’t seem likely for an issue where one power on to the next you get different results. (Presuming the same gcode is used each time)

Hi, I’m using MKG Gen L 2.1 (based on ramps). I did minor modifications in the firmware provided by V1 to make it work. Just a correction from my post, the machine moves slowly only sometimes. I did a test and powered on and off several times, but its speed was ok most of the times.

Good power on means the machine moves with a speed that seems normal, based on videos I saw. Bad power, the machine moves slowly.

Just to add. I did a 100mm movement in the Pronterface when the machine was moving fast. However, in practice, the machine moved 250mm on the table.

I know it might be something in Marlin, but what seems strange is this modifications in speed after power on and off.

What stepper drivers are being used on the MKS ?
What this seems like to me is that sometimes Marlin is configuring the stepper drivers correctly, and sometimes it is not. When modern smart stepper drivers aren’t configured, they default to some pre-configured settings.
Is your firmware marlin 2 based? If so, we want to look at the diags post. boot from Marlin.

Yes, it is Marlin 2.0.x (do not remember right now the exact number), I’m using TMC2209

The default_axis_step_per_mm is set to 200, 200, 800

DEFAULT_FEEDRATE is 50, 50, 15

The movement that I tried was on the Y axis.

What do you get with an M122? Try both when it isn’t working and when it seems to be working.
The TMC diagnostics will be interesting to see.

M112 says all motors are OK.

I found an issue. My steps default axs steps per mm is set to 200, 200 and 800 in Marlin.

However, the comend m503 shows it is set to 100, 100, 400:

I managed to solve the movement issue by adjusting steps per unit using M92. I had to down it to X40 Y40 and Z500. I dont know why. Maybe it is some setting related to the steppers and my board.

Btw, anyone knows why the m500 does not store the settings in EEPROM? When i turn off and on, the old setting are restored.

The issue regarding slowly movement I found an issue here that I’m gonna test:

Thank you @azab2c @MakerJim I managed to found the solution and posted here. Not yet for the strange slow movement, but at least it is solved by powering it on and off.

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Let us know if you completely solve it. It’s a very odd behavior.
I wonder if it is somehow related to your issues with saving EEPROM, and getting weird values at times.

I’m glad you were able to find a workaround.

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I can think of two reasons for the slow movement. First, if your CAM is not generating federates early in the file, then Marlin will use the last set federate. This federate can some from anywhere including you electronically moving your router. Examining your g-code files in a text editor will quickly allow you to see if this an issue.

Second, Marlin has a federate percentage. It can be set using an M220 g-code. It is also set when the display is in Marlin mode the dial is rotated.