Drafting Tips for perpendicularity (Tolerances)
Drafting Tips for perpendicularity (Tolerances)
(OP)
Hi,
I'm a materials engineer, with little experience of technical drawings, so i'm a little stuck. I need to find the nominal value and tolerance values for a feature.
I have the perpendicular symbol, with 0.03 after it. Does this mean that the inspection values are...
Nom 0
Lower limit -0.03
Upper Limit 0.03
or
Nom 90*
Lower Limit 89.97*
Upper limit 90.03*
i wish i had a copy of drafting for dummies! I searched on the 'net, but i need it explaining in laymans terms...
Cheers,
Rich
I'm a materials engineer, with little experience of technical drawings, so i'm a little stuck. I need to find the nominal value and tolerance values for a feature.
I have the perpendicular symbol, with 0.03 after it. Does this mean that the inspection values are...
Nom 0
Lower limit -0.03
Upper Limit 0.03
or
Nom 90*
Lower Limit 89.97*
Upper limit 90.03*
i wish i had a copy of drafting for dummies! I searched on the 'net, but i need it explaining in laymans terms...
Cheers,
Rich





RE: Drafting Tips for perpendicularity (Tolerances)
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: Drafting Tips for perpendicularity (Tolerances)
Is the perpendicularity applied to a cylindrical hole or to a flat surface?
In either case, perpendicularity is not a plus/minus tolerance and is not an angle that is measured in degrees. It is the size (thickness) of zone that the feature just barely fits into, and the zone is constrained to be exactly square to the datum feature. A perfect feature has a perpendicularity value of zero, and the value goes up as the feature tilts. There is no negative value.
Nominal 0
Upper Limit 0.03
Lower Limit N/A
Evan Janeshewski
Axymetrix Quality Engineering Inc.
www.axymetrix.ca
RE: Drafting Tips for perpendicularity (Tolerances)
Thanks for the help so far. I understand a lot better, however,Axym and fcsuper, they seem to contradict each other?
Rich
RE: Drafting Tips for perpendicularity (Tolerances)
"Good to know you got shoes to wear when you find the floor." - Robert Hunter
RE: Drafting Tips for perpendicularity (Tolerances)
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RE: Drafting Tips for perpendicularity (Tolerances)