Why Basic Dimensions
Why Basic Dimensions
(OP)
Why use basic dimensions. Since these are theorectical in nature why use them? Many engineers I work with cannot explain a 'basic dimension' but they use them and then do not add a feature control frame. When confronted with this situation they tell us to use the block tolerances. It drives us QC guys nuts.





RE: Why Basic Dimensions
RE: Why Basic Dimensions
http://www.answerbag.com/q_view/1884027
Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion
RE: Why Basic Dimensions
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Why Basic Dimensions
Think of controlling position of a hole which is in the center of a very simple rectangular plate with its three perpendicular planes assigned as datum features A, B & C.
The aim of basic dimensions is to unambiguously define how the positional tolerance zone of the hole is theoretically located and/or oriented relative to datums A, B & C whereas position tolerance value describes the size of a tolerance zone.
Now imagine that you have 8 holes in the plate also dimensioned by basic dimensions and controlled by position tolerance. This will create a set of perfectly located and oriented tolerance zones within which every axis of 8 holes has to be contained.
Similar concept can be used for profile and orientation controls.
I do not know if it helps, but at least it is not a definition from the standard.
RE: Why Basic Dimensions
You said, "Somebody needs to go back to school." I challenge this statement because I don't think this stuff is taught in school; which is part of the problem.
Matt Lorono, CSWP
Lorono's SolidWorks Resources & SolidWorks Legion
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RE: Why Basic Dimensions
I agree.
Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion
RE: Why Basic Dimensions
"Good to know you got shoes to wear when you find the floor." - Robert Hunter