Max Print Volume with support

[flyntm 2]

I'm trying to print a large part on a U3. Essentially, it's a flat disk that's mostly flat on one side and some simple vertical features on the other. On the flat side, there's a small circular recess in the center. The disk is large enough that Cura forces me to turn off SUPPORT so that it will fit on the build plate. OK... I understand why it's requires that for any support that might be needed towards the outside of the disk, but I only need a small amount of support for the recess in the center of the build plate. It seems that it should be doable, but I can't figure out how with in Cura. I have tried turning on support and setting the "Support X/Y Distance" to 0 but that does not do it.

Thanks for your help.

[tinkergnome 927]

I can imagine only one support setting that has an influence on the build volume, that's "Horizontal expansion"

Here are the support settings well explained: Cura Support Settings