3D carving machnine idea?

[Tristar500]

I've got an idea I've been kicking around.

I want to carve foam statues (mostly people).

Rather then the typical 3 axis setup I'm thinking of a design layout that has a rotary axis for the y. The Y axis because it is rotary rather then linear so it would allow carving all the way around (think totem pole carving)

I can see this machine being used to copy a statue by fitting the z axis with a touch probe to scan and then simply run the gathered info back with a spindle. The scale could also change with no problems.

So... I've got a machine that can copy stuff but what if wanted to design something in cad and machine it? Y axis runs on polar geometry.

Any relatively cheap programs that can deal with polar geometry?

I've got Bob Cad up to V 23 but I think it's strickly linear xyz.

Any thoughts?

[ger21]

MeshCAM can do indexed cutting, but you'll need a real Y axis and a rotary A axis. But it's cheap. Also look at Deskproto.

[RICHARD ZASTROW]

This was done back in the late 1970's/early 1980's. Demonstrated at IMTS.

They had a router on a vertical post and a copy probe on a set up similar to your idea.

The subject was rotated on a table with a probe displacing horizontally. After each rotation, the probe displaced vertically and repeated. Basically a duplicator. The data from the probe was recorded digitally while the router reproduced the subject in a block of graphite in real time.

Pretty heady stuff for the time, eh?

Dick Z

[Switcher]

This isn't really 3D, with this program you can swap a linear axis, with a rotary axis. I havn't tried the program, but a few guys on the vectric forums have, the results look really good.

The program name is "CncWrapper" ($20), If you search the vectric forums, Andrew (wrote the program) had posted a free version, in one of his older threads.

[bostosh]

"Any relatively cheap programs that can deal with polar geometry?"
Just use normal point/vector cutter centerline (clfile) output X,Y,Z,I,J,K,F
And a postprocessor to convert to any machine comfiguration.

[Tristar500]

Originally Posted by bostosh "Any relatively cheap programs that can deal with polar geometry?" Just use normal point/vector cutter centerline (clfile) output X,Y,Z,I,J,K,F And a postprocessor to convert to any machine comfiguration.

Not sure exactly what you mean. Can you elaborate please?

I've got a three axis mill running Mach 3, Bobcad 21/23

Are you saying I would need to write a post to do the conversion from linear to rotory (polar)?

[svenakela]

MadCAM, a CAM-plugin for Rhino can do this.

[svenakela]

The downside with having your idea is that you cannot mill the center of the head if it has an area that is covered, for example if there's a hat on the head. But if you're ok with doing some hand shaping just go for it. On the other hand, by making a fourth axis (rotational milling head) you can reach it all. It makes the machine a little more advanced but still doable. MadCAM can still handle the machine.


Here is a more advanced way of your idea.

YouTube - Sculpting a Large Bust of Bethoven

YouTube - Sculpting a Large Bust of Bethoven

EDIT: On the other hand, if you always base the statue on a given diameter, it shouldn't matter if the axis is straight or rotating. It's just a matter of doing some math before setting up the machine.