Hey all,

I have been all over the net and I can't seem to get step-by-step help to get my 4th axis aligned and calibrated for 3d model carving.

First a bit about me and what I am trying to use my CNC machine for. I am a character artist and 3d modeler. I have worked for the last three years for dreamworks and Disney modeling characters for their themed attractions. I have worked with fabricators using 6 axis KUKA machines and I am now trying to do 4 axis milling out of my garage. I want my cnc to carve figurative models (or pieces thereof) out of wax, plaster, or foam.

Now about my CNC. I purchased a chinese-made 3 axis machine (40" x 24") with an added worm reducer/chuck to be used as a rotary table. I am using Mach3 to control the CNC, I have installed al my limit switches, set up my soft limits, calibrated X, Y, and Z. I am using deskproto to generate my tool paths.

Here are my issues....

1) The Rotary table did not come with any information about steps or pitch and it needs to be calibrated. How do I do this? Can I just use a test indicator?

2) How do I set up Mach3 so that it turns the RT in degrees instead of distance?

3) The RT is not fixed to the work surface. Can I pick a spot to mount it and create a new home position for XYZ when using the RT and retain my original home settings for 3 axis work?

Any help or links would most appreciated.

Thanks,
Ralph