It's hard to believe we're still having this conversation, as I had called in an oddball occurrence I experienced on a drawing back in the UGFM days in the 80s. I had sent in a part example where the left end width dimension of an extrusion didn't match that of the right, even though the ends measured exactly the same width. I only discovered UG had this left vs. right problem by chance when I changed the location where I had initially placed the dimension. This was way back in the BBS days, and yes, I seem to remember John was involved in this conversation back then, helpful as always. That problem was addressed and fixed in a later point release, but the same thread showed up again back in 2005. Here's a snippet: Re: Dimensional rounding Thanks for your help Daryl. I looked back and read the posts. Guess I need to start using the "Search" button more. Thanks again. Daryl Pierman wrote: >We've recently discussed this here ad nauseum. The software will >correctly round your .0625 value off to .062. Similarly, a value of >.0635 will correctly round off to .064. This rounding off method is not >only statistically more accurate, it follows various accepted standards >from both ANSI and ASTM. > >The rounding off takes place only when the discarded digit is exactly >5. In a nutshell, if your last significant digit is even (in your case, >the "2" in .0625) the depicted value rounds down. When the last >significant digit is odd, the depicted value rounds up. > >Unigraphics has done this correctly for a very long time. There was a >bug back in the late 80s related to this, but it was corrected. If you yourselves (or your kids) have been taught the wrong rules in school, bring the teacher a current copy of ASTM E 29 or a cancelled copy of the old ANSI Z25.1, and follow the advice of an old EDS guy (Ross Perot), "If you find a snake, kill it". It might be the only way John won't need to explain this anymore. Daryl (soon to be retired as well)
Yes, this came-up so often that back when I was still working I had a copy of my response as a Word document and whenever it was needed I could simply 'copy & paste' it into the appropriate forum where is was suddenly an issue again.
John R. Baker, P.E. (ret) EX-Product 'Evangelist' Irvine, CA