For over a year now with dozens of pieces of expensive fire wood at hand. Carving an island topo I cannot get a smooth transition between the topo carve and the relief part of the carve.I believe the reason is the topo is positioned at Z location measured from the bottom of work piece (read from the spoil board up). The relief Z is measured from the top of the work piece down, so no matter how precisely the work piece is measured there will always be a discrepancy. Am unable to make a smooth transition, the detail cut will always end above or below the roughing relief cut.
I have a couple of suggestions.
1)set the topo carve base measured down from the normal Z 0. same as the relief,
2) Vice versa set the relief Z from the spoil board up,
Same as the base of the topo.
3) Include the relief portion as part of the detail carve.
Would take longer but it would just be machine time.
Today I set Z with a1 2 3 block (both roughing and detail bits) set both bits with router at set Z, bits resting on the 1 2 3 block when tightening the collet and still got a ridge between the detail bit and the relief. Advice would be welcome, as mentioned I have been working on this for more than a year now, I want to put topo carves into the floor of bowls.