Inverting the carving design

[Kreig]

I designed up a simple railroad crossing sign with an outside circle, big “X” cross and the two R letters. Decided I would like to carve everything except the above items, meaning how can I reverse the carving so the letters, cross and outside circle are not carved?
Thankyou.

[NeilFerreri1]

Create a circle of the save size cut to your desired depth. Set the cut depth of the design to zero.