Centroid Community CNC Support Forum

Hi,
Has anyone had a problem with artifacts with 3D carving with a ballnose bit? This is the first 3D program I have ran since upgrading to CNC4.62.
Is it a settings issue? The program was created with Vectric Aspire.

Have you run this job before without issues?

It would help if you could post the Aspire file. To me it looks like the step over of the bit is too high and maybe you had a direction change in the offset clearing field.

File attached of the Aspire program.

Yes, I have run a similar job without problems. The step over is 7%
.

By any chance did you have smoothing set up other than the basic settings from Centroid on the Acorn- such as @sword's settings? I had to re-configure the smoothing settings in the Acorn after upgrading to 4.62.

Some of the artifacts show up when I preview the tool path in Aspire until near the end of the program with the offset tool path similar to your photos. When I change the BN tool path to raster, they do not show up in the preview. From your photos compared to the preview, it almost appears as the entire tool path may not have completed on the 3D carve/texture.

I have smoothing on, one of the defaults. The program finished after running 4-1/2 hours. Do you have any recommendations for these settings?
Thanks

Should I set it back to precision router?

Probably several things happening here. First, when doing 3D work, when setting up a job in Aspire, I'll never use anything lower than "Very High 7X Slower" for resolution. This helps to keep the pixel size smaller in relation to your job size. That setting should be fine for the size and bit combination you have. Next, the only time I'll ever use the offset strategy is if I'm doing something round or like a bowl. In this situation, offset is too random or all over the place. This allows any stress changes in the material, as cutting proceeds, to change the depth of cut from when it starts an area and then returns later or comes from the other side to finish. Using a raster strategy keeps the progress more even from one side to the other, never coming back to an area that was partially cut. If your version is one of the latest, you can enable "New Raster" in Edit/Options. This improves on raster path ordering. 6% - 8% stepover should be good for a 0.25" BN, but if the tool happens to have poor geometry, it can leave marks or ridges.

Another thing you can do to try to pull a bit more detail out of that texture, is to increase the shape height a little. In turn, you'll have to lower the base height.

That said, your material may need better hold down to overcome any changes due to stress changes as the offset cut randomly proceeds. That and using a raster toolpath will eliminate the "ridges".

Next, and this can be machine and accel/decel settings capability dependent, but if you are running default precision router smoothing, the change in Z depth will be considerably smoothed out, which will eliminate the grain texture in your file. For example, I run a lot of higher detail scene designs and many may have a log cabin. With precision router, the logs are turned into plywood siding as the abrupt up/down toolpath is considerably smoothed out. Read up on the various smoothing parameters and how they affect the the toolpath and run some tests to find a "3D Relief High Detail" set of values that work for your machine. The one setting that has the most to do with detail in 3D files is P226 (W). Attached are my 3D relief fine settings. More detail on smoothing here...viewtopic.php?f=63&t=4580 and also the smoothing manual...https://www.centroidcnc.com/centroid_di ... manual.pdf

Any time that you update your version of CNC12 and manually set it up instead using a report, you can copy over your smoothing setting by copy/paste the ad2_presets.xml into the new cncm folder and your presets are back in place.

Scott

You might want to drop down to a smaller ballnose as well. The 0.25" ballnose doesn't fit between some of the letters, thus the needed negative offset, which takes off some of your letters width.

Wow, Thanks for all f the great advise, I will give it a go today!