Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Tolerancing on a Max dimension

Tolerancing on a Max dimension

Tolerancing on a Max dimension

Hello all:

I'm new to the forum and have a question that I hope can get answered. We have a customer that calls out 4 mm Max on a clip opening. The opening sometimes close after processing because the material is spring steel. The same customer does not want closed clips and sent this explanation to us. It doesn't make sense to me.


See attached part print and the areas I have highlighted with a red box. There is a note that specifies that any untoleranced dimension has a tolerance of +/- 0.8mm. Since the gap in the clip has a specification of 4mm MAX, this implies that the upper limit of the tolerance is 4mm, therefore the minimum spec would be 2.4mm (4.0 – (2 * 0.8)).

Or in other words, the actual tolerance range is:

2.4 – (-0.8) – (midpoint) – (+0.8) – 4.0

because 4.0 is defined as a maximum allowable spec.

Thank you all for your input.

RE: Tolerancing on a Max dimension


What standard does your print conform to? In Y14.5-2009 the term "MAX" has special meaning and typically means that the dimension can vary from 0 to the specified "MAX" value unless there is a minimum limited by some other feature/constraint. See section 2.5 of the standard - I don't believe that once "MAX" is called out it is any longer considered an untoleranced dimension. I would avoid the use of MIN/MAX especially if it is an important feature and have the customer change their print - it can cause a lot of confusion in its interpretation as you can see, they should have supplied a tolerance band that is acceptable instead of just a max dimension.

RE: Tolerancing on a Max dimension

I agree with chez311... MAX and MIN dimensions are considered absolute limits (per Y14.5) with no other applicable tolerance.

"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

RE: Tolerancing on a Max dimension

Me three. Putting max on a dimension means it could go to zero and still be OK. There is no lower limit. They need to change their drawing if they need a minimum value and then you can requote because you are either going to need some kind of control or scrap non-conforming product.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close