Hello again everyone,
Been testing the router with some engraving and works fine.
Now trying out a cut… but saw that it didn’t go as deep as expected. So tried a few things and found out that for a depth of 9mm it goes about 3 mms deep.
What can i check? Steps? ( have not altered the firmware for skr pro 1.2 )
Thank you
The typical reason for this issue is that you purchased a 1-start instead of a 4-start lead screw. If that is the case, you will have to adjust the steps per mm or swap out the lead screw and nut. Adjusting the steps per mm can be done from a display (if you have one). It can also be done in g-code using an M92 and then saved using an M500. I believe for a 1-start lead screw; you want to increase the steps per mm by a factor of 4.
Other reasons for your issue include having the micro-stepping wrong, or the grub screws on the connector between the stepper and the lead screw are loose. Microstepping would only be an issue if you used A4988 or DRRV8825 drivers. These drivers have you set the microstepping and the current on the board rather than in firmware. A lose grub screw will produce inconsistent results, losing step/gaining steps as the job went along.
Note if the issue is a 1-start lead screw, continuing to use it will increase your Z torque but reduce your max Z feedrate, and you will likely want to adjust the max feedrate in the firmware to avoid losing steps. See M203.
@robertbu Drivers are tmc 2209 by BTT and a loose screw might not be the issue, as the results are consistent. Wrong, but consistent 
Will check and adjust the steps and feedrate.
How do i know visually if my screw is 1-start leadscrew?
Thanks for your assistance
How do i know visually if my screw is 1-start leadscrew?
Pull your Z axis out and look at the exposed end of your lead screw. A 4-start lead screw will have four threads starting at the end of the lead screw. You will get four grooves starting at the end as well. See this image and this image. Your Z being off by around 4X is another strong indicator that that the lead screw is the culprit.
checked the screw, and it was as suspected. 1-start screw. Fortunately i could change the settings from menu, without the need for a reflash ( both steps and feedrate ).
As always, you guys are life saviours!
Special thanks to @robertbu
Something to take into consideration, you won’t be able to move your Z as fast with a single as you would with a 4 start. On the plus side, singles don’t drop as much when the power is pulled from the stepper.
@barry99705 from what i have read you have the benefit of greater torque but with reduced speed.
I’ll do more tests( depending on time … ) and will post the results.
You can improve your max feedrate for Z by increasing the voltage from 12V to 24V for your SKR Pro board…assuming you are currently running it at 12V.
