The Problem
- A client had constructed a model using Matrix for a stereolithography build process but was having difficulties getting a build which would fit his chosen stones. The other detail which was also important were the facets inside the shank.
- The solution I used was to angle the wax so as to be able to reach both the outside and inside surfaces with the same milling setup. Using two separate milling setups would have introduced major alignment problems.
- The process of developing the correct model and procedures to yield the correct geometry and accuracy involved quite a few iterations, with the original model actually being redrawn in attempts to eliminate modeling artefacts as the cause of some inaccuracies. The green tool path model has been reworked often enough that it doesn't quite still fit together properly. But since milling doesn't require watertight models it sufficed. In the end the problems were discovered to have resulted from hardware problems.
- The tool path model is a combination of the unrolled round ring (inside and outside), added constructed parts, and surfaces to limit milling depth. It is necessary to remember that the tool path software only "sees" the model looking straight down along the Z axis, and compensates for the cutter shape. In this case I opted for a long tapered vee tool in order to get good corner details.
- The angle of the wax was chosen to be as low as possible while still allowing clearance for the long tool shank.
- With the long tool all of the cuts had to be very light so as to avoid deflection and chattering.
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Rhino detail
- Screen shot from Rhino
- I simplified a little, the chamfer on the inside was eliminated
- Milling on an angle did have its costs, the right side of the baguette hole couldn't be fully milled with the tooling I chose to get sharp corner details. Just a little extra work for the setter.
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Milling setup
- A photo attempting to show the setup on mill
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