Code help with offset cope...?

[00750]

Hey all, I'm new to the boards, so I'm not sure if this is the right section to post in...Anyways, I'm a bit new to writing CNC programs. I've recently done a program to cut a square in the side of a pipe, along with a program to cut a cope. Both were fairly straight forward.
My next goal is to write programs for an offset cope in the side of a pipe. This would include a program to cut the oblong (oval) hole in the larger diameter pipe, along with a program to cut an offset cope in the end of the smaller pipe.
The cope program I have now can probably be modified slightly, but I'm not sure of the math formulas needed...same goes for the oval hole in the larger pipe.

If anyone could give me a hand It would be greatly appreciated!

Thanks,

Casey

[HuFlungDung]

Beats me about formulas, but I'd use a solid modeller to create the intersection I needed in cad first, then machine it with cam.