Tolerance Calcs 1

[ctopher]

Just thought this may be helpful to any of you.

http://www.engineersedge.com/Calulators_Online.shtml

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP2.0 / PDMWorks 05
ctopher's home site
FAQ371-376
FAQ559-1100
FAQ559-1091
FAQ559-716

 

[drawoh]

ctopher,

You do realize don't you that the formulae for GD&T positional tolerances are very simple?

For a screw passing through a clearance hole into a tapped hole, the positional tolerances equal one half the diametral clearance, based on MMC values. For a bolt passing through two clearance holes, the positional tolerances equal the diametral clearance, again, based at MMC.

Most of the time, I do the arithmetic in my head. Without the convient tables, people might consider alternate GD&T schemes like setting the positional tolerance to zero (usually but not always at MMC), using holes as datums.

JHG

 

[ctopher]

Yes, I know. Thanks drawoh.
The link is just for anyone that does not understand it and want a visual tool. Just for info.

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP2.0 / PDMWorks 05
ctopher's home site
FAQ371-376
FAQ559-1100
FAQ559-1091
FAQ559-716

 

[ewh]

ctopher,

I also do the math in my head, or scratch it down with other numbers I'm working with, but this is a good tip. The site has alot of good reference information other than GD&T.

 

[Tunalover]

It's scary to think that there are people who would use those calculators without understanding what they are doing!


Tunalover

 

[ctopher]

I was taught to do it by hand. But, these days I hear the excuses all the time from engineers and designers that they either don't have time (too busy) or why do it if it is available online.
Sometimes when I get very frustrated with coworkers, I catch myself doing the same. Or sometimes if I'm rushed, I may use the online site for check.

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP2.0 / PDMWorks 05
ctopher's home site

FAQ559-1100
FAQ559-716