Does this look about the right amount of clearance with the z-axis at its lowest?

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My plan is to have two pieces of wood for the bed, the top one being sacrificial. I've assumed the shortest cutter would stick out about 25mm and allowed this much clearance from the top of the first spoil board. This should allow for the top board to be resurfaced a few times and still give enough travel on the Z. Am I about right with this?

Cheers