here's an exaggerated platform:
note how it sits below center-line of the edge you'd be working?
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this shows the underlying ridge material/mass. the ridge-line essentially indicates the orientation that you'd like to align your tine with.
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here is how i would try to support this piece for the removal. note how i try not to allow the ridge to come into contact with the palm of my hand.
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and here is where the tine would make contact (after abrading):
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continue with inward pressure (into the ridge) until the platform gives.
please excuse my plastic tine. it's the eraser end of my pen for my wacom tablet.