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


Hex Callout - How to Interpret?

Hex Callout - How to Interpret?

Hex Callout - How to Interpret?

Hi All,

A seemingly simple dilemma, but I was not able to find a firm answer. Is the "HEX" callout in the attached drawing to be interpreted as flat-to-flat or point-to-point? I cannot seem to find a solid reference on how to interpret this. Nothing in ASME Y14.5 from what I could tell. The drawing specifies "HEX" but it only shows a side view. I'm assuming .50" from flat-to-flat.

Thank you in advance.

RE: Hex Callout - How to Interpret?

It is indeterminate. At the least, if the part is made with .50 across flats and that is wrong, the part can be reworked to .50 across corners. That said, I don't have any idea why anyone would dimension across corners. Confounding is that the section appears to be across corners.

RE: Hex Callout - How to Interpret?

99.999% across flats 1/2" Hex You just don't specify a hes across points.

RE: Hex Callout - How to Interpret?


The ASME Y14.5-2009 "square symbol" is used with the dimension across flats, so it's probably a reasonable extension of principle that "HEX" would be used the same way.

What sort of drawing did you find this in?


RE: Hex Callout - How to Interpret?

Always good practice to provide sufficient views/dimensions/notes/etc on your engineering documents so that no interpretation is required. Usually doesn't require much additional effort.

In the example shown, even if you assume the hex dimension is .50 across the flats, there is nothing specifying what the flange profile is between the local hex flats. Are the hex corners sharp, rounded, or some other profile?

RE: Hex Callout - How to Interpret?

Thank you everyone for the replies.

pylfrm - Not much else was provided with the attached picture other than some basic notes and a rudimentary title block, so I cannot say.

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!


White Paper: Rapid Manufacturing with FDM
The automotive industry is increasingly turning to additive manufacturing, and fused deposition modeling (FDM) specifically, as a reliable alternative to traditional metal-cutting methods, like milling, turning and boring. Download Now
White Paper: Revolution in Design
Open up new possibilities for your business by changing the way you think about product development. Compared to traditional methods, 3D printing offers advantages that allow you to make more innovative products and get them to market faster. Download Now

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