I just ran your program in graphics on a Haas lathe and there are no problems with it as far as I can tell. With the correct tools you should get the rings off correctly.
I do notice in your post this: "We have three tools, a facing/top-trim tool (Diamond-shaped), .......".
The tool you use for facing is not suitable for turning the OD profile. A facing tool has to be positioned in a 'handed' manner for front or back facing but your profile tool needs to be positioned symmetrically. I have uploaded a sketch showing this. I think all you need to do is put in a tool for the OD profile that is positioned as shown and you will get symmetric rings.
It is not necessary to use tool compensation but you will have to take into account the tool nose radius in your coordinates. |