CNC Hotwire Attachment

[Hawkeye]

Since I just got into lost foam casting and recently finished an X2 CNC conversion, it occurred to me that it would make sense to use the CNC mill as a base to cut foam patterns for casting.

I made up a frame for the wire to clamp to the Y-axis motor and a couple of support arms to attach to the mill table to hold the foam workpiece.
   

The nichrome wire came from an old crock pot that my Mom wanted to use as a planter. I've had the wire for a few years. Now I have a use for it. The wire is supported by plastic blocks with brass bolts to adjust the wire for squaring it up to the table.
   
   

I'll experiment with the arms to try different methods of fastening foam blocks for cutting. Maybe pointed bolts threaded through the sides to stick into the block or clamps to hold it down on the horizontal flanges.

I powered the wire using a 12 VAC, 50 VA transformer controlled by a dimmer switch. A test cut on a piece of 1" blue foam shows that it cuts quickly and cleanly. I'll make up a test run in G-code one of these days to put it through its paces.