Hi guys. I have been ill recently with the dreaded Cancer but now under going surviellance. Fingers crossed. So over the past few days I decided to give myself a lift and start using my MPCNC. I have come across an issue. The part I’m trying too cut is 584mm x 324mm. When I cut the part out it measures. 590mm x 324mm. Think it was an easy Step/mm calibration needed I carried out the formula need divided by actual then times by steps in Epprom. Redid the cutting and absolutely nothing changed. If I minus 20 of the Y axis Step/mm I consistently get a length of 590mm, I at a loss. Can anyon shed any light on this for me.
Check that the grub screws holding pulleys to the motor shafts are tight. If they slip you’ll see a consistent dimension error on that axis.
I’d also suggest trying moves of different lengths as a troubleshooting step. If the error is variable with the commanded distance, it’s more likely to be steps/mm. If the error is always the same amount, then I look for a physical/mechanical issue.
The decrepancy increases the further the y axis moves, i therefore thinks it’s the steps /mm but every time I change the steps the Y carriage moves the same
Are you sure your changed steps per mm setting is getting applied? If you’re using Marlin, you may change the steps per mm with a gcode command, but if you don’t save the settings they’ll revert to saved when the board resets.
What controller are you using? That way, folks familiar with your board can pitch in to help sort this out.
Yes everytime I change the Steps/my for the Y axis I save in repetier host and the disconnect the CNC before restarting software and reconnecting, all setting are then checked in Epprom and are saved successfully.
The controller is a MKS Gen v1.4
It’s very confusing. So I’ve gone out to clear my mind. Considering reflashing the controller with Marlin after saving epprom settings as a text file. Only really need X & Y axis Steps/mm
Hope someone could shed light on this issue. Im perplexed
As asked earlier, I’ve tried doing variable lengths and the error increases with distance so I believe it’s Steps/mm
The X axis is bang on too within 0.02mm
Just can’t get it too work it constantly gives 5mm greater that the item being cut on the y Axis. The error depends on the size of the item. The longer the item, the bigger the error. Which leads me too think it’s got to be the Steps/mm. But as said before everytime I change the Y steps, save, confirm. The error is consistent
So I’m going to reflash the firmware and re calibrate. I’m just checking to make sure I use the correct one. Can some one point me to the correct version
I’m using Repetier Host
I built the original version of MPCNC
MKS Gen V1.4 controller
Everything else were the spec requested in the build
I have done some further testing and have a consistent error on the Y axis.
If I move the Y axis 100mm it moves 101mm
Similarly moving the Y axis 200mm it moves 202mm, 300mm it moves 303mm, 400mm results in a move of 404mm im sure you get the idea.
So using the epprom Steps/mm for “Y” in Repetier Host I calculated the new value and inputted it, using M500 and restarted too check it was saved and no change.I did this about ten times slowly reducing the Steps/mm value with no improvement.
In desperation I set the Yaxis Steps/mm to a value of 1.00 and tried moving the Y-axis again asking for a move of 500mm resulted in a move of 505mm
Does anyone have any ideas as the other axis’s have calibrated perfectly.
I redrew an item but this time instead of making the long side of the rectangle the length I required I drew it 99% the length, the width was drawn exact…… is this waffle or are you following
So I want a rectangle 324 x 585
I drew the part 324 x 578 and the part cut was exact to what I wanted being 324mm x 585mm
Depending on what versions of firmware you’re using, the storage location for specific settings may have changed. I’d suggest doing an M502 (Factory reset) to ensure that values are all in the right slots, then make and save your changes, then load them back from EEPROM.
Let me state! Very glad to read this. I know battling cancer is not fun, but I love it when i read someone is winning their battle. I hope a very clean future for you!!!
for what comes next