which software do you have? vcarve pro or aspire ?
in reguads to model thickness,
if you select your model in aspire on the modeling tab 4th row down, there is a icon like a cresent wrench.
click on it and you can change your model properties. like thickness there is also a scale z thickness of model on the same line
as far as having model on the surface when you go to the toolpathing side under material setup, you can adjust your model location in the block of wood.( you want it to the top of course)
woodmizer sawmill and joe's hybrid cnc, a good combination
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