Roland mills not completing finishing passes on roughed areas of crowns

[tuyere]

Hey all,
We've been seeing an occasional issue on several of our Rolands where the the roughing passes are completed, but some or none of the finishing passes are. Looks like this:




It looks like what you'd get from a tool broken mid-job, but on inspection the tools are fine, and we can continue milling other jobs afterwards with no issue. The simulations for these parts look fine, and I believe it's repeatable- if you re-run the job it will also fail to finish the roughed areas in the same way as before. I'm waiting for another case to come up so I can confirm the repeatability, I'm not 100% on that.
We're using Millbox 2022 on DWX-52Ds and -51s, but for what it's worth, this was also happening when we were running MB2020.

 

[Jane Qi]

Hello, @tuyere . I'm Jane Qi. Nice to e-meeting you again.

If other jobs complete without problems, but the same symptom recurs only for this job, it might that there is something wrong with the job. According to the photos you posted, it looks like there is no finishing tool path only for this part. Would you please double check the tool path as well? Thank you.

 

[tuyere]

Hello. We've gotten a few more cases like this, and in all cases the simulation shows a complete or near-complete milling job with no material left behind where it is on the part in real life. What was more interesting was that I re-nested one example on a new puck, so generating a new toolpath with new supports, slightly-different angular orientation, etc- and got basically the same result, on a different mill. As before, the mill produces great parts afterwards with no tool change. In one case, it only half-completed the finishing toolpath for a single unit from a job of 6- so it selectively decided to not finish milling the third part from a set of 6, correctly milling those that came afterwards. It's odd. The areas that aren't being milled are often highly-accessible to the tools, so it doesn't seem to be an issue of inaccessible undercuts or what-have-you.
I don't have mreason to think this is a machine problem, at this point, so I'll probably have to follow up with the CAM/millbox side of things. Thanks for reaching out and offering your assistance, though!

 

[CoolHandLuke]

simulation shows a complete or near-complete milling job with no material left behind where it is on the part in real life

this means the data flowing to the mill is interrupted; check your cords that they arent near magnets, check the v panel that it is up to date, and check that the cord connector is secure.

 

[tuyere]

I don't know, the fact that I can repeat the defects across multiple mills with different jobs at different times- and the patches of unmilled material are basically identical across each part- makes me think this isn't something transient like that. We don't stream jobs from Millbox, we export them to individual PCs used as dedicated CAM stations, because we did used to get those kinds of errors when we were trying to stream jobs all over the milling room via too-long USB cables from one machine. I can set up and run one part one day, and then re-nest it as a new job, run on a completely different mill and different PC the next day, and get a mirror-image defect- it's repeatable in a way that seems effectively hardware- and setup-agnostic.

That's all still sensible stuff to double-check on, though, yeah. A simple hardware issue like that will be an easier fix than something weird at the CAM level.

 

[DentalDen]

Interesting stuff guys I’ve had the same issues but never had the brains to work out why it happens I think software but I’m no expert

 

[CoolHandLuke]

I don't know, the fact that I can repeat the defects across multiple mills with different jobs at different times- and the patches of unmilled material are basically identical across each part- makes me think this isn't something transient like that. We don't stream jobs from Millbox, we export them to individual PCs used as dedicated CAM stations, because we did used to get those kinds of errors when we were trying to stream jobs all over the milling room via too-long USB cables from one machine. I can set up and run one part one day, and then re-nest it as a new job, run on a completely different mill and different PC the next day, and get a mirror-image defect- it's repeatable in a way that seems effectively hardware- and setup-agnostic.

That's all still sensible stuff to double-check on, though, yeah. A simple hardware issue like that will be an easier fix than something weird at the CAM level.

easy to check, just simulate the file. if simulation shows complete milling, but real product is bad, it has to be a data issue and i'd have a good long talk with millbox if it doesn't show fully milled in sim.