4th Axis Setup - EMC, Sherline, BobCAD-CAM

I am running EMC BDI-LIVE 02-JUN-2004

A Sherline 2000 Mill.

The Sherline Driver Box and Sherline Stepper motors.

I have used this to successfully cut PC Boards so I assume that the
EMC program is setup correctly on the X, Y, and Z axises.

I just got BobCAD-CAM v19.6 and have been through most of the
training videos and for the normal X Y Z it appears to generate the
NC code correctly.


Now throw in the 4th axis...

First of all after I got BobCAD-CAM I find that it does not really do
4th axis as one would think it does. If you want to make a cylinder
in BobCAD-CAM you have to unwrap it and draw it as a flat surface
then as you send it through the CAM side of BobCAD it is supposed to
convert it to use the "A" axis form one of the x y z axises.


I've been through the lessons and have tried it over and over for the
past few days, and I still can not get it to work right.


What should be a simple box (outline) with rounded corners that is
milled onto a cylinder winds having arc errors in EMC.

I can get a simple box without rounded corners to mill but I have to
manually go in and edit the feed rates since it tries to use the same
feed rate for linear and rotary moves. Ie: 5 inches per minute
equates to 5 degrees per minute on the rotary side (which is
extremely slow on the rotary side)


Does any one else have a similar setup that is working right, any
tips?


Thank you

Harry - AB2PN