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


When should I use the FRTZF tolerance frame?

When should I use the FRTZF tolerance frame?

When should I use the FRTZF tolerance frame?


I'm fairly new to G,D and T and I am trying to incorporate the principles in the drawings I make. I understand how composite frames work and how PLTZF and FRTZF tolerance zones are constructed. However, I am yet to see a practical example when I might want to use the FRTZF tolerance frame. The examples where I have used it so far for locating bolt patterns, I can make do with just the PLTZF tolerance zone. Are there any examples out there that I can refer to for this?


RE: When should I use the FRTZF tolerance frame?

Short answer for now:
http://www.tec-ease.com/gdt-tips.php; --there are some examples here.


Datum Feature References
Second Segment
Using a Note Video!
Several Examples Video!
Feature to Feature Control Video!
Composite l Video!
Composite ll Video!
Composite lll Video!
Composite l Gage Video!
Composite ll Gage Video!
Composite lll Gage Video!

Also the standard itself (2009)could be an excellent source of examples for what you are looking for.

RE: When should I use the FRTZF tolerance frame?

Think of an electric outlet on the wall at your home. That's a pattern of holes where both the upper and lower portions of a composite tolerance are useful. (For now let's ignore the fact that they aren't round holes...)

If I want to control the location of those holes on the wall, the overall position isn't terribly critical. I could perhaps give you a half-inch position tolerance of the holes as measured from the corner of the room. But now zoom in locally on the holes that make up the outlet: the hole-to-hole locations have to be way better than a half-inch in order for a plug to fit! Those hole-to-hole tolerances might only be allowed .080 inch.

Result -- the PLTZF would be my overall tolerance within the room: .500 for each hole with respect to datums A, B, C. But the FRTZF would be the local tolerance: .080 for each hole while only looking at datum A (the plane of the wall itself).

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

RE: When should I use the FRTZF tolerance frame?

A shelve should be mounted on the wall with some brackets/sets of holes in the brakets. Position on the wall is more forgiving than the hole to hole pattern relationship in order for the holes in the wall to fit the pre-made holes in the brackets.
Also the FRTZF should have a primary datum feature to limit the horizotal hole alignment ( the shelve should be usable and the goods place on it should not rollover/ fall from it).

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!


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