Hi guys, I need some input. I have a part with a datum structure consisting of -A-(3 datum targets on a contoured surface, -B- a 12 x 5mm slot and -C- another 12 x 5mm slot. There are a few profile callouts referencing B at mmc and C at mmc.

My question is this: The bonus tolerance -C-contributes is from the 5mm width as this is the direction that the datum applies. Datum -B- locates in both the width and length of the slot so where is the bonus tolerance to going to come from.

I have attached a sketch.

Bill Reilly
Quality/Technical Manager
Quality Inspection Technologies

mmc_problem.jpg
mmc problem (35,297 bytes)