In my role as CAD Manager from time to time i get a question that seems to only have one answer, one which i hate but i'm hoping you smart folks might be able to help me not to not use, that is "because I said so..." We are currently working with sheet metal parts where the mounting holes are the critical dimension(s) the part overall dims are not as critical i.e. holes are 3 place dim's and overall part maybe 2 places dim's. in the past when doing ordinate dimensions I have always kept all the precisions in the set the same, when 0.000" is origin then the last will be 3.312" in order to lessen the tolerance to the final i would add a +/- tolerance not change the precision to that particular dimension. Is there a CAD standard (other than ASME Y14.5, checked there first) that speaks to this or have I just got this rule stuck in my head? Thanks for your comments and insights
Ps I realize I could just have them change to linear dim's but ordinate are cleaner on this particular part.