Settings with a 2mm pitch Z lead screw

LowRider CNC Advice
1

Yes, yes, yes don’t mess with the golden yellow path … but it happened by accident
I sourced locally in Europe, and ended up with a lead screw with 2mm pitch which I figured out was wrong, but it’s there now and I’ve got some things running, so I’d like some confirmation on what other settings I need to change to allow for this lead screw

I’m using Jackpot/FluidNC and have changed:
steps_per_mm to 400
acceleration_mm_per_sec2 to 20

I thought I saw a comment about Estlcam Rapid Z settings also, so I’ve dropped this to 300

This seems to have got me working - but is there any other settings I should be aware of when using a 2mm pitch lead screw on my Z axis?

(If anyone has an EU source for the ‘right’ lead screw I’d appreciate it, otherwise I’ll get one from Aliexpress sometime)

Thanks,
Tom

2

I also went the non standard route of 2mm pitch lead screws, and I am a very happy I did. Honestly not having the gantry fall every time there is not power is so nice. In terms of changes, the only thing I have adjusted is the steps, and has been working fine.

3

If you’re using a jackpot it might be worth checking

axes/z/max_rate_mm_per_min

If it’s too high you can get skipped steps.

4

Just double the steps per mm and youre gtg.

5

Any view on what “high” would be here?

6

I did have some weird Z behaviour, where it would seem like the Z would go continuously deeper/lower and not raising between sections, which caused me to explore other settings. Still nervous!

7

You probably want to start at half the default, maybe a little more but that would need testing.

What I onserver was if the router was on the far left side then x max could raise and lower fine but the weight of the core would cause the x min side to skip steps.