huangyhg

repeated basic dimensions
if a basic dimension is repeated in separate views of a drawing, does this pose a problem for interpretation in any way or violate the standard? the dimension of course applying to the same feature in both views.
the drawing of course being prepared 'in compliance with asme y14.5m-1994.'
i looked could find no conclusive statements.
thanks
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normally it will not be a problem, if the dim is to the same points in every view. i don't like to do this. i dim basic once, then ref the dim in other views if needed. there is usually no question if done this way.
chris
solidworks/pdmworks 08 3.1
autocad 06/08
i agree with ctopher. i don't think it's stated not to, but i definitely use only one "true" callout per drawing. whether basic or not, if repeated, i use a reference dimension in the "inconsequential" view.
v
to all:
ctopher and vc66 have it right. if you repeat the same dimension to the same feature in separate views, the feature is double dimensioned.
say in 6 months, the dimension changes, and a new employee gets to make the change. suppose he doesn't know about the 2nd dimension, and the drawing gets released? which dimension is the correct one?
i hate using reference dimensions! they can (and have been) dangerous, especially when the 'main' one has changed and the (ref) hasn't.
regards..
teddykaye
in my situation, pro engineer is used for modelling and the dimensions are associated so that should tend to negate confusion from changes in the future.
i had thought that i had seen 'somewhere' by a gd and t guru that it was allowable. anyone recall such?
that's assuming, of course, that the new employee knows enough about pro/e to use associated dimensions, and not just create them in the drawing. believe me, i know from experience.
by somewhere, do you mean on eng-tips?
v
vc66,
not necessarily there, don't rem where.
ringman,
showing the same dimension in two places is bad practise. showing one of the dimensions as a reference dimension would be the prefered way.
if you are using 3d cad such as proe or solidworks, both of your dimensions will be updated by any changes. i prefer to apply fcfs somewhere close to the basic dimension. if there are two basic dimensions, i can convert one of them to ±, or i can apply an fcf to each one and make them disagree.
how about it is bad practise, but not has bad as it used to be.
jhg
ringman, out of interest, why are you considering repeating the dimension?
i was in a similar quandry a while back but then thought it thru and made the second dimension reference.
kenat, probably the least qualified checker you'll ever meet...
kenat
you would have to see the drawing to appreciate or understand the logic. a radius in indicated in a very small view then additionally in a detail where the holes are positionally toleranced. it rather seemed to make the definition more clear. and that should be the object of the drawing in the first place.
so you're repeating it in the detail view? i'd lean towards reference dim if any but like you say, i'd have to see the drawing.
kenat, probably the least qualified checker you'll ever meet...

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