Roland mill ?

[Ryan Gottlieb]

We have done several hundred zirconia crowns with a Roland mill now and love the results. they are usually very smooth with lots of detail, but sometimes they come out with a bumpy "topographical" look. what would cause this? the same thing happens form time to time with PMMA.

thanks

 

[Marcusthegladiator CDT]

What software is rendering your cnc?
The topography look is because the copings were not externally finished.
And if they were, the wrong bur and/or incorrect "step" was used, but this is unlikely.
And more likely your strategy is out of order or missing the final external finish step.
This could also the result of the model you imported. If it isn't a cut and dry coping, but rather something a bit strange looking...
The software didn't recognize all the curves properly and the delimination instructions are all screwy. You can try adjusting and reexporting the STL and see how it goes.
I'm glad you like your Roland as I root for the underdogs. And also look forward to the day when mills cost even less so we can all have one.

 

[DMC]

good answer.

 

[Ryan Gottlieb]

thanks for the great answer. i don't actually own a Roland mill, i send my files off for milling.
Thanks