My present work involves multiple alterations between machining and epoxying. After the epoxy has set I need to machine the excess back to surface before machining the next color.
My current workflow is to zero 0.50 mm above the surface and cut to 0.50 mm below that zero for the re-surfacing part. Then I lower the bit 0.50 mm and re-zero for the actual machining. Epoxy and repeat.
I would love to be able to just declare the substrate’s surface as zero for both types of CNC operations but this doesn’t appear possible from my research so far. Ideally I could set the surface as zero and, for the re-surfacing part, set the Start Depth to -5.0 mm but CC won’t allow negative numbers here.
Anything I can do to obviate this continual re-zeroing?
Thanks, seems that might work. I’ll give it a shot.
I suspect my epoxy work is different from yours. Some of the bits I’m using have a diameter of 0.15 mm and a DOC of 0.5 mm. These wouldn’t even make it through the surplus epoxy. Even the larger bits are working to their max DOC from zero Z, the largest bit I typically use is 0.50 mm.
How accurately do you set the first Z Zero? If you have confidence that it is 0.5mm, then why re-zero to the actual surface? You can tell your pockets to start at 0.5mm deep, which would be right at the ‘true’ surface.
When working with inlays, I usually set my Z Zero to the top of the piece, then immediately move up a round number of mm to just above the plug. I set that now as my Z Zero, and do everything from that reference. I’ve never felt the need to re-zero down to the piece.
Thanks, that all makes sense. Although I’ll stick with Tod’s suggestion for this particular workflow. Each project requires 20 to 30 separate toolpaths, too many chances for error entering the offset depths and not satisfactory visual feedback on conforming to the bits LOC.