I'm getting up the nerve to turn some Eucalyptus burl cap.

I want to make into a natural edged bowl (hopefully nested set).

I've got a fair amount of experience using coring chisels on local stuff
like cottonwood and maple.

I want to start out by coring the bowl blank out of the cap and then
turning the remaining cap into a platter preserving as much as the outer
edge of the cap as possible.

For my project I don't want to waste any by mounting it to a face plate
leaving screw holes. So I need to use a waste block glued to the flat
bottom of the cap. The question is what glue? Should I use a large
thick piece of say maple and mount it to a face plate or a smaller piece
that can be held in a chuck?

So far I've had a couple suggestions of using CA glue (even though the
burl is several years old it is still wet) and using titebond. One
suggestion was use titebond with paper between the waste block and the
burl. The paper would permit me to separate the waste block from the
burl more easily but I worry about the stresses during coring.