`
200x16/266.67 = 12
This is the steps/mm from my working marlin firmware.
Doing some more testing: 2020 x 370mm long extrusion.
**From Z0 to 20mm move, the extrusion is too low from the nozzle.**
---
### Author:  [@Xboxhacker](https://klipper.discourse.group/u/Xboxhacker)
#### Post date: [June 19, 2025, 7:39pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/6 "2025-06-19T19:39:25Z")
**From Z0 to 370mm move, the extrusion is too high.**
---
### Author:  [@Sineos](https://klipper.discourse.group/u/Sineos)
#### Post date: [June 19, 2025, 7:51pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/7 "2025-06-19T19:51:39Z")
z-velocity seems far too high for such a lead-screw
Try something around 10 to 20 with an accel of around 100 to 120.
---
### Author:  [@Xboxhacker](https://klipper.discourse.group/u/Xboxhacker)
#### Post date: [June 19, 2025, 8:15pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/8 "2025-06-19T20:15:39Z")
Same results, NG. 😑
---
### Author:  [@Sineos](https://klipper.discourse.group/u/Sineos)
#### Post date: [June 20, 2025, 7:11am UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/9 "2025-06-20T07:11:42Z")
It seems unlikely to be a Klipper issue. More likely a mechanical issue and/or wrong `rotation_distance`.
- The too far movement on 20 mm points to a wrong `rotation_distance`.
- The insufficient movement on 370 mm points to a mechanical issue or skipped steps.
Of course, given the measurements are correct.
---
### Author:  [@Xboxhacker](https://klipper.discourse.group/u/Xboxhacker)
#### Post date: [June 20, 2025, 4:11pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/10 "2025-06-20T16:11:50Z")
Ok, did a lot more testing. Tries a shotgun approach with different `rotation_distance:` values. It would seem that 12 is the closest. Went from 8-13. I also turned down the accl and velocity to 8.
**Here are some observations.**
On this machine, when homing, the bed goes all the way to the bottom. There are 2 opto switches, one left and one right. The bed can tilt left or right since the motors are independent. When homing the Z, once one opto is triggered, the other motor continues until the second opto is triggered. This is now the +600mm of the printer. If I move up 100mm (`G1 Z500`), from the bottom optos, it moves 100mm. If I move up 500mm (`G1 Z100`), it has moved ~530mm. No matter which `rotation_distance:` is used, it is always off on the linear movement over the distance of the total movement.
I realize that Kilpper recommends using `rotation_distance: 8` for the TR8x8 threaded rod, even AI said so 🤣. When I use 8, the bed will crash the nozzle at a reported height of +190mm. Crazy amount of Z offset.
Since I have been fighting this for a week now, I had to flash the machine back to Marlin to get some work done. And it works 100% as it should.
I want to use Klipper for its rich features, but I am absolutely defeated.
Next thing I am going to try is maybe a different PI. Maybe a `rotation_distance: 4`. Maybe upgrade to ball screws.
---
### Author:  [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)
#### Post date: [June 20, 2025, 5:36pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/11 "2025-06-20T17:36:02Z")
Can you post an image of one of the lead screws with the scale of a (metric) ruler close to it?
---
### Author:  [@hcet14](https://klipper.discourse.group/u/hcet14)
#### Post date: [June 20, 2025, 6:22pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/12 "2025-06-20T18:22:13Z")
> [@Xboxhacker](#):
>
> If I move up 100mm (`G1 Z500`), from the bottom optos, it moves 100mm. If I move up 500mm (`G1 Z100`), it has moved ~530mm. No matter which `rotation_distance:` is used, it is always off on the linear movement over the distance of the total movement.
Is it always the same “off” amount when doing this test with different `rotation_distance:` values?
When you use a `rotation_distance:` of 12 or 8 there is no difference to +30mm?
Just trying to understand the problem right!
---
### Author:  [@Xboxhacker](https://klipper.discourse.group/u/Xboxhacker)
#### Post date: [June 20, 2025, 6:40pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/13 "2025-06-20T18:40:19Z")
Have to wait till Monday to get a picture with the ruler.
It is on every for single rotational distance. It is off by a different amounts per rotational distance.
I should have written down all the data. I did not. I will see what I can do next week. Right now the machine is working with Marlin again, there are things that I need to complete before I can mess with this again.
---
### Author:  [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)
#### Post date: [June 20, 2025, 6:51pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/14 "2025-06-20T18:51:31Z")
> [@Xboxhacker](#):
>
> Have to wait till Monday to get a picture with the ruler.
No more need for that.
I found documents that confirm the use of T12 lead screws: [Tronxy VEHO 600 Ball Screw Upgrade Kit - 680mm](https://www.tronxy3dprinter.com/de-de/products/tronxy-veho-600-ball-screw-upgrade-kit-for-veho-600-series-3d-printer-t12-lead-screw-680mm-c7-12mm-dia), [Tronxy Z-axis T8/T12 screw rod with copper nuts – Tronxy 3D Printers Official Store](https://www.tronxy3d.com/products/tronxy-z-axis-screw-rod-with-copper-nuts?variant=40153277726898)
---
### Author:  [@Xboxhacker](https://klipper.discourse.group/u/Xboxhacker)
#### Post date: [July 2, 2025, 6:54pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/15 "2025-07-02T18:54:13Z")
**UPDATE:** I got it working; it still needs a little fine-tuning tho.
Gonna try and explain the issue and “resolution”. FYI `rotation_distance: 12` is 100% correct.
**Recap:**
On this machine, when homing, the bed goes all the way to the bottom. There are 2 opto switches, one left and one right. The bed can tilt left or right since the motors are independent. When homing the Z, once one opto is triggered, the other motor continues until the second opto is triggered. This is now set to +600mm of the printer (in the original cfg `position_endstop: 600`).
The guide I was following said to:
```auto
PROBE_CALIBRATE
SAVE_CONFIG
```
Then
```auto
Z_ENDSTOP_CALIBRATE
SAVE_CONFIG
```
The `PROBE_CALIBRATE` set the probe offset to -3.4mm.
The `Z_ENDSTOP_CALIBRATE` set the `position_endstop = 585.38`
But it **should** have been `position_endstop = 588.780`. It took the probe offset away from the `position_endstop`. This is why the prints were getting messed up, and why the prints were over 3mm too tall.
I am not a Klipper expert; this is my second dive into Klipper. So I may be wrong still. 🤣
The stock Marlin would move the bed down to the bottom, trigger both optos (tilt if needed), then return to the top and stop at the probe on the carriage. This would be `Z0`. Then the offset would be about -3.7mm from the probe to the nozzle.
How can I accomplish this with Klipper? The bed still needs to flatten out at the bottom optos, then rise up to the probe and set `Z0`. The `position_max: 600` would still be the same. But the travel from the bottom to the probe would be a soft limit?
---
### Author:  [@system](https://klipper.discourse.group/u/system)
#### Post date: [August 31, 2025, 6:55pm UTC](https://klipper.discourse.group/t/new-klipper-install-on-tronxy-veho-600-need-help/23942/16 "2025-08-31T18:55:01Z")
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