Rounding or not of tolerance in FCF with Dual Dimensioning
Rounding or not of tolerance in FCF with Dual Dimensioning
(OP)
Just a general question
When dual dimensioning a print that has GD&T. When converting the metric tolerance in the FCF, do you round if the 4th number is over 5? example - .4mm = .0157 would you round up? or leave it at .015?
When dual dimensioning a print that has GD&T. When converting the metric tolerance in the FCF, do you round if the 4th number is over 5? example - .4mm = .0157 would you round up? or leave it at .015?
Solid Edge V20





RE: Rounding or not of tolerance in FCF with Dual Dimensioning
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
Solid Edge V20
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
http://www.tec-ease.com/tips/september-05.htm
http://www.tec-ease.com/tips/august-05.htm
SeasonLee
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
KENAT,
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What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
I think we have had this discussion a couple of times.
Do not generate dual dimension fabrication drawings. Use one set of units to show requirements. Provide the alternate units for reference, only.
On a 3D CAD package like SolidWorks, you can get away with some stupidity, since the computer is working out the dimensions and the conversions. The numbers in your FCF almost certainly are typed, and you are manually calculating each conversion factor. What is the shop allowed to do when the numbers do not agree?
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
Powerhound, GDTP T-0419
Production Manager
Inventor 2009
Mastercam X3
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
Yes i do know that's the better practice. but, this is customer generated and sometimes, even knowing were not product designers, we have to draw there part up to there standard.
Solid Edge V20
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
h
Chris
SolidWorks 08, CATIA V5
ctopher's home (updated Aug 5, 2008)
ctopher's blog
SolidWorks Legion
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
But, Ty everyone for everyones post's. I do agree with rounding up to the rules that i learned as a young man and stated by other's.
Solid Edge V20
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
By definition, dual dimensioning is a form of soft conversion, which is explicitly disallowed by ANSI/ASME Y14.5 (regardless of the release).
Also, when converting tolerances, you create two different (though similar) tolerance ranges which allows for for more than one interpretation of each specification, which is also explicitly disallowed by ANSI/ASME regardless of the release.
Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
I hate it but we do make some dual dimension prints this way.
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
RE: Rounding or not of tolerance in FCF with Dual Dimensioning
This is a very true statement. But, like in my shop, the guy's will look at the non metric thats in the brackets.
Solid Edge V20