G-Code Help

[RobieMo]

Thanks for the feed back from everyone. I will play with it and see what I come up with. I am surely not doing a good job of describing what is going on, but i am certain it is not a result of feed rate. It makes perfect oval passes then comes back and makes distinct cuts where I don't want them.

I will try everything that you all have suggested, including the changing the feed rates, and see what happens. Thanks again for taking the time to try to figure this one out. I know its a simple project, but fixing the problem will save me lots of time in sanding.

Rob

[rungemach]

If you step through the toolpath one step at a time ( it takes a while) you can see the issue that is happening. It goes by too quickly otherwise.
Not sure why it is generating a cut path like this, (where the bit returns to places where it previously cut) but at least it is visible as you watch the toolpath doing the cutting, step by step.

Ideally you would like a toolpath that started at the top of the workpiece and spiraled its way down to the finish depth and completed one final smooth pass there.

I use an inside profile with the plunge and feed rate set to the same speed, then set a ramp distance of a little less than the circumference you are cutting.
The result is that the bit ramps down into the material and does not change speed as it transitions from ramp to straight cut (for smoothness).
I do that often with circles, with very good results (in aluminum) , but never had a need to do it with elipses.

I added a new toolpath to your file. try having a look at how this cuts as it eliminates the return cuts and ramps its way down.

bob