"Closed" dimensions
"Closed" dimensions
(OP)
Guys,
I'm suffering memory loss and need some help and possibly a reference [standard] to verify but I've always known "closed" dimensioning to be wrong.
This is where you have:
|<----- 1 ----->|<--------- 2 --------->|
as opposed to this:
|<-----------------3 ------------------>|
|<----- 1 ----->|
Help me out - is this a will/shall type thing or a best practice and more a result of getting more out of your tolerances? I'm struggling to remember and I browsed through an old engineering drafting textbook and couldn't find anything on it.
Thanks,
I'm suffering memory loss and need some help and possibly a reference [standard] to verify but I've always known "closed" dimensioning to be wrong.
This is where you have:
|<----- 1 ----->|<--------- 2 --------->|
as opposed to this:
|<-----------------3 ------------------>|
|<----- 1 ----->|
Help me out - is this a will/shall type thing or a best practice and more a result of getting more out of your tolerances? I'm struggling to remember and I browsed through an old engineering drafting textbook and couldn't find anything on it.
Thanks,
Jack Lapham, CSWP
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RE: "Closed" dimensions
Figs. 1-19 & 1-20 in '09 or 1-17 & 1-18 in '94 may be also helpful.
RE: "Closed" dimensions
If the dimensions are basic then the 2 schemes are equivalent.
As pmarc says 14.5 has a little bit on this, but maybe not in the detail you want.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: "Closed" dimensions
Say you had +-.005 on all the dimensions in your examples.
it could be:
<----1.005--->|<--------2.005------>|
for a total of 3.010 max dimension.
while for the other method
3.005 would be the max dimension.
but this could happen:
<-----------------3.005-------->|
<-----.995---->|
implying:|<-----2.010----->|
Just depends on the type of control you need.
RE: "Closed" dimensions
RE: "Closed" dimensions
Jack Lapham, CSWP
Engr Sys Admin
Dell M6400 Covet (24 Season 8, Ep 22)
Intel Core 2 Duo T9800, 2.93GHz, 1066MHZ 6M L2 Cache
8.0GB, DDR3-1066 SDRAM, 2 DIMM
1Gb nVIDIA Quadro FX 3700M (8.17.12.5896)
W7x64 | sw-01: 55.92
SolidWorks 2012 sp3 x64 & EPDM sp2