I mill big sculptural pieces of polystyrene foam on a home-built machine that is 4000mm long, by 2000mm wide, with a Z movement of 900mm, sometimes flat and sometimes using an A axis. An example of one of these A-axis pieces could be a human head. I fix the block for the head to the A-axis chuck using a flat cut at the neck, and if the piece is long, I give it some support at the top of the head, in a tail stock. I use DESKPROTO for G codes, wonderful for the job, working from .stl files from a DAVID SCANNER.
Doing things this way generates an AWFUL lot of waste, polystyrene dust that’s very bulky and difficult to dispose of ;-(.
There are companies that offer polystyrene milling machines combined with hot-wire cutters. They economize on both waste matter generated and on milling time by first roughing out the form (human head for example) using hotwire cutting, before milling, then classical A-axis milling to produce the finished article. A wonderful idea…..
I´m trying to figure out how MACH Lathe could be used to control a hotwire function, to cut profiles along the X axis with the A axis stationary, and once done, continue in the normal rotary milling way, to achieve basically the same.
How I see it is this: Somehow I generate let´s say 4 sets of G-codes for the four outlines of a human head: one for the (front) neck- chin-lips-nose-eyes-forehead-top of head, one for (side) neck-jaw-right ear-side of head-top of head , another for back of neck-back of head-top of head, and lastly one for (other side) neck-jaw-left ear-side of head-top of head: in a word, four silhouettes or profiles.
My question is, Could I then program MACH Lathe to “cut” each of these profiles, travelling along the X axis, having set up a hot wire cutter, but with the A axis stationary, not rotating, just to get a profile? I would leave maybe a 10mm skin in this roughing stage.
I would then do this another 3 (or even 7 more times to get a roughed-out octagon ) times, spinning my A axis 90 degrees each time (or even 45º) and thus removing almost all surplus material before milling to finish. Hope I´ve explained myself ; )
Anyone got any ideas? I´m getting fairly familiar to MACH Mill, but Mach Lathe is unknown territory for me so far.
Any input grateful, many thanks as ever,
Frank Norton.
www.franknorton.com