Hi Justin
Here are a few files to demonstrate how you can generate lathe toolpaths using Cambam. "Beadmm.dxf" is a drawing of your part. Note that the centerline is aligned with Y, which we intend to eventually convert to Z. I suspect your problem may have been that you had the centerline aligned with X on your drawing. The origin is set such that when on the lathe, X0 will be the lathe centerline and Z0 will be next to the chuck.
"Beadmm.cb" is the Cambam file. I've divided the curve into 8 segments. (simply click and drag to select the desired segment, then select the profile tool. Do this for each segment in the order you wish them cut) The odd numbered segments are where we want the toolbit to cut as it is moving away from the headstock, and the even numbered segments are where we want it to cut as it's moving towards the headstock. If this were a milling operation, the former would be conventional milling while the latter would be climb milling. So for each of the segments, select the appropriate MillingDirection in the "Spindle Control" section. Select the feedrate, then select machining > produce gcode.
With a text editor such as notepad, open the gcode file you've just created (Beadmm1; it actually looks almost identical to the Cambam file). Delete all of the lines, in their entirety, containing a Z value. Change the G20 to G21 if you're using mm, and not inches. Change the G17 to G18 to denote that you are using the XZ, not the XY plane. There may be some other codes such as S0 (spindle speed), M3(spindle on, CW rotation), M5 (spindle stop), and M6(tool change), which don't apply to your setup. You can remove them, though they'll probably just be ignored by the control if left.
Now use edit > replace to change all of the "y"s to "z"s, and save the file. The resulting file will give you the finishing pass for your part, however, the end of each segment will be linked in a straight line to the beginning of the next, so the last bit of editing you need to do is add a line for an x retract, such as g0 x8, at the end of each segment. The resulting file is "Beadmm2".
This doesn't include any roughing cuts, but you can easily add them to your drawing and use the same procedure to generate the toolpaths.
The actual file run in the video is "cnczone4.ngc". It's not pretty, a reflection of a lot of hand editing and me learning what works with wood...
Hope this helps you get started.
HR |