【转帖】dimensioning method

yang686526

dimensioning method
i’m pretty sure my description of the problem will be inadequate but they take ip fairly seriously here and i don’t think i’m meant to post parts of drawing on the web.
a designer has a plate approximately .5 thick around 3.5 square.  it has 2 v (rad at tip) grooves in it through the .5 thickness.  they are at a compound angle so looking at the 3.5x.5 faces it has an angle in both orientations.  due to the angle, on one of 3.5x3.5 sides they have a relatively large v, on the other side fairly small.
what’s the simplest way to dimension it?
the 3 ideas i have are either:
dimension the angles of the grooves in the relevant orientation and then give the general shape of the cut on the larger cut side along with its location.
second idea is to dimension the size/shape/position of the cut on both sides and essentially have the cut generated by lofting from one to the other.
third is to create a view normal to the direction of the cut in order to define its shape and size, then give start and end points on each face.  or i guess start point on one face with the angles again.
i’m thinking that surface profile is almost a must so the dimensions would be basic.  the tolerances can’t be too large which could easily happen given the number of dimensions that go together to define the geometry where as i think surface profile will enable better use of the available tolerances.
fyi i’m in the us and try to follow asme y14.5 pretty closely.
please ask for any clarification.
thanks a lot.
kenat, probably the least qualified checker you'll ever meet...
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i would use two section views, each down the center of one leg of the v channel.  if i understand your situation correctly, dim'ing should be easy at that point as long as either end of the v groove is also detailed.
matt
cad engineer/ecn analyst
silicon valley, ca