Threading op (Lathe) - Stepper stuttering

[brassmanwithaplan]

Hello,

I've been running my converted lathe for just over a year now and I'm very happy with the Acorn board/system.

I've just begun experimenting with threading but I'm having some issues.
I'm using an OMRON encoder 1:1 using a timing belt from the spindle. I've had no issues using consant surface speed or other encoder related processes.

I usually use Fusion360 with the Franco export settings.
The Z axis stepper motor makes a noise which implies it is struggling, stuttering or missing steps etc however it does just about cut a thread on multiple passes (terrible finish). I tried running a thread op solely in CNC12 CAM but it was much worse, the Z axis would 'jam' a stutter in one place before returning to the start point and attempting a 2nd past etc (stuttering again and so on, also in this case it also did not follow the correct thread lead and caused double cresting)
This is apparent even when cutting air or slowing the spindle speed, coarse or fine thread.

As mentioned, I've been happy with everything else and general turning with no issues what so ever so I'm a bit stumpted.

New report attached.

-Dan.

[Muzzer]

Good to see the report but you are going to be asked for more details about the steppers, the drives, the installation, stuff like that. Posting some pictures of the machine, cabinet, motors etc is helpful.

Currently we know you have an unknown lathe, an Omron encoder and a problem with what sounds like lost position.

[brassmanwithaplan]

NEMA 24 + M542T drivers
Lathe is a Myford ML7 running the saddle on bed for Z and X on linear rails.

[cnc_smith]

Dan,

We also need the fusion 360 g-code program and you said you did a program in the CNC12 CAM software. Need the Intercon program (not just the g-code program) from this also. You sated you tried slow RPM and again we can see what RPM you are running without the programs.

[brassmanwithaplan]

Not quite sure what you need for the intercon program? I'm assuming what I have attached for that one is not what you need?

[cnckeith]

brassmanwithaplan,
hello. while probably unrelated to you post, please take the time to update to version Acorn CNC12 v4.5 which is the current release. so we are all using the same software when helping you debug an issue.

here is how.. viewtopic.php?f=60&t=4457

[brassmanwithaplan]

brassmanwithaplan,
hello. while probably unrelated to you post, please take the time to update to version Acorn CNC12 v4.5 which is the current release. so we are all using the same software when helping you debug an issue.

here is how.. viewtopic.php?f=60&t=4457

Thanks Keith,
It keeps slipping my to-do list. Completely forgot about the update

[martyscncgarage]

Not quite sure what you need for the intercon program? I'm assuming what I have attached for that one is not what you need?

You didn't post the intercon file generated when you used CNC12 to create a threading cycle.

Marty

[brassmanwithaplan]

Not quite sure what you need for the intercon program? I'm assuming what I have attached for that one is not what you need?

You didn't post the intercon file generated when you used CNC12 to create a threading cycle.

Marty

The file "conversational thread test v1.cnc" is the one generated from using CNC12 CAM to create the threading cycle. If there's an additional file from this somewhere other than the .cnc , I'm not aware of how to find it.

[martyscncgarage]

Not quite sure what you need for the intercon program? I'm assuming what I have attached for that one is not what you need?

You didn't post the intercon file generated when you used CNC12 to create a threading cycle.

Marty

The file "conversational thread test v1.cnc" is the one generated from using CNC12 CAM to create the threading cycle. If there's an additional file from this somewhere other than the .cnc , I'm not aware of how to find it.

Intercon creates an ICN file that should be located in the c:\icn_lath directory