Worked this up ages ago:
This was from the old Shapeoko forums.
Yes, I made it, it seemed to work in testing.
The hardware was (from memory)
- 1/4" steel rod (I think I wanted to use music wire but it was too thick, so used an alu. rod)
- bronze thrust bearing
- two washers (to hold things vertically)
- 1/4" drill stop (to hold things at the bottom)
I think there might be comments in the code, and it may be possible to look it up on the Wayback Machine.
It’s around somewhere, but since then I’ve had to rearrange the basement on a rush twice now (replacing the furnace, then the water heater) and a third, more purposeful rearrangement is slow going.
There are lots of better designs — posted this 'cause it was asked for, and it could be milled out — probably w/ a bit of patience one could work up a design which could be drawn up in Carbide Create.
3d_printed_dragknife.scad (7.6 KB)