# GD&T Examples?

• 02-06-2019, 03:34 PM
richard_fox
GD&T Examples?
Hi

I have a basic understanding of the principles of GD&T but I am left clueless of how and when to apply it.

Though I can find info on the principles - I can't find any 'realistic examples'.

I guess it must be like learning to ride a bike but I feel that I need a helping hand to get me going.

Can anyone please point me in the right direction.

Richard
• 02-06-2019, 04:34 PM
Kelly Bramble
Geometric Boundaries II, The Interpretation and Application of GD&T per. ASME Y14.5-2009

That book and all kinds of other stuff here:

[url]https://www.engineersedge.com/Engineering_White_Papers/Dimensioning_and_Tolerancing/[/url]
• 02-08-2019, 02:20 AM
richard_fox
I have taken a look at the ISO version of the book (i'm in the UK) and it looks good but it's not what I'm looking for.
I need something which can help me understand dimensioning and gdt with design intent.
I am a draftsman who wishes to broaden my engineering skills.
I create drawings from the engineers models but have always had difficulty understanding their design intent - I'll look at the assemblies as to where components go and tend 'not to see the wood for the trees'.
Some of the interactions of the components are not obvious so determining datums to dimension from is quite challenging.

Regards

Rich
• 02-08-2019, 03:57 AM
Cake of Doom
Is it actual, worked examples you'd like?
• 02-08-2019, 06:51 AM
richard_fox
Hi
Yes worked examples would be great to get me on track.

Regards

Rich
• 02-08-2019, 07:05 AM
Kelly Bramble
[QUOTE=richard_fox;15574]
I need something which can help me understand dimensioning and gdt with design intent.
[/QUOTE]

Not sure what you're envisioning, but it's all there in the book you looked at.. Assigning dimensions and tolerances is not like solving a math problem or installing a battery procedure.

Dimensions and tolerances are assigned by fit requirements, functional requirements and lastly form. Or... identify the fit requirements between parts based on functional requirements. <-- that's the simplest way to view it.

What you need is formal training and a full understanding of dimensional specifications and their function.
• 02-08-2019, 07:15 AM
jboggs
When I was in your position the greatest amount of learning I got was from simply going through old drawings of mechanisms and systems that I already understood. That way I was able to understand how the designer identified what features and relationships were important to him, and how he expressed that importance on paper. (Ah, the good old days of rifling through big flat file drawers with thousands of old paper drawings, all of which expressed their own "artistic style".) Take every opportunity you can to stop and very closely examine old drawings. Take the time to ask yourself how the designers went through the thought process of creating them, step by step. You'll learn a lot.
• 02-09-2019, 07:21 AM
richard_fox
Thanks for your responces, I will talk to my manager to see if time can be spared to do as you suggest jboggs and to talk to the engineers as well as to why they did something in a certain way.

Cheers

Rich