Buckydome Update

Buckydome Update

By: Josh Rucinski

Well. The EPVC works better than I expected.  It machines quite nicely, the only minor flaw is that it wants the upcut bit constantly, otherwise the cut tailings tend to weld themselves quite nicely to the sides of the cut kerf.

The best way I've found to machine both sides is to provide a registration dowel, or peg system.

Cut holes about 1/8” into the substrate surface through the material that is already mounted onto the CNC and ready to be flipped over.  Cut the holes to be whatever the dowel dimension you have is.  I highly recommend at least 1/2” for reasons I will bring up later.

1.      Be sure the marks will flip the piece with precision.  To do this, place the holes in relation to a mirrored CAD line of the material.  Do not measure anything from the physical edge of the material. This will make a sloppy transfer.

2.      Use the upcut bit, 52-910 or something like it.  The hole should be flat bottomed and very clean. Cut the hole about 1/8 past the material onto the sacrificial substrate on top of the machinebed.

3.      Prepare the dowels so that they have no chamfer or bevel, this will give you better accuracy, however you will have to carefully deburr the dowel's cut edges.

4.      When the piece is ready to be flipped, unscrew it and place the dowels a bit past the new side so that they can fall into place.

The system is not totally perfect because the bed itself must be perfectly flat, which ours cannot be because it is in the blue barracks, every leveling is temporary, because the ground is not stable.  However, if your design has a bit of play, it will work within a tiny fraction of an inch, and much more accurate then anything by hand.