Dave G wrote:

I have to put in a new sink disposal in my kitchen sink. The drain
pipe coming out of the wall is copper. Can I cut the exsisting brass
trap out and replace it with a PVC trap and attach it to the copper
wall drain pipe. The wall drain pipe also has a threaded brass ring
that I would cut off to accommodate the PVC trap. I dont know whether
it is acceptable to combine PVC and copper or does it have to be brass
and copper.
Thanks Dave G

You can mix and match any materials as long as they are
approved locally (if that matters).
Don't cut the threaded ring off till you are sure
you won't need it.

Jim