huangyhg

alignment between hole and slot with unilateral tolerances
hi all,
i need to tightly hold the alignment between a hole and a slot. the hole has a unilateral postiional tolerance from the tertiary datum and i also want to allow a more generous unilateral tolerance between the slot and hole. the competing priorities i described seem to preclude the use of composite control frame but maybe i'm missing something.
my first attempt at gd&t is attached (mm dims), but it was rejected since i was told i can not gd&t a centerline between features.
any ideas?
jim
lastviking, i think maybe there's a mix up on terminology. assuming you're working to asme y14.5m-1994 and have a copy available then take a look at figure 5-41 & the text of section 5.9.
essentially you can put one tolerance in one direction, and a separate tolerance in another. i think this will meet your needs.
kenat,
thanks kenat, that does get me part way there. any idea how to utilize unilateral tolerancing with true position? i don't see that in y14.5m-1994.
or do i just need to change my nominal to the center of the unilateral zone and make it bilateral?
your latter option is probably the way to go with position tolerance.
with surface profile you get more options on unequal bi-lateral or unilateral but i don't think it's appropriate here.
kenat,

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