gd&t help provide better design
gd&t help provide better design
(OP)
All gd&t textbooks state the benefits of GD&T are:
Improves Communication
Provides Better Product Designs
Increases Production Tolerance
I got first and third one, but I don't see good examples showing "provides better product design". From these statements GD&T is more than just a drafting tool, but a design tool. I'm in a position to convince people in department to use more gd&t but have limited knowledge and experience on this topic. So anyone minds sharing some good examples?
Improves Communication
Provides Better Product Designs
Increases Production Tolerance
I got first and third one, but I don't see good examples showing "provides better product design". From these statements GD&T is more than just a drafting tool, but a design tool. I'm in a position to convince people in department to use more gd&t but have limited knowledge and experience on this topic. So anyone minds sharing some good examples?





RE: gd&t help provide better design
Some very simple example: I saw the drawing of a part, simple rod with diameter being held to +/-0.0005 in. The said diameter didn’t actually fit to anything. It was fully exposed. It was almost like designer didn’t know about surface texture symbology and it was his attempt to say that surface of the part should be nice and smooth.
So as you are trying to apply your symbology properly, you also evaluate the part for its function and unnecessary cost.
RE: gd&t help provide better design
But knowing the function may drive a more specific and accurate tolerancing scheme. For instance: if the part is a motor shaft that will be rotating at high RPMs, then we should be concerned about wobble and vibration -- in GD&T this would lead us to focus on a runout tolerance. However, suppose the part doesn't rotate; maybe it is just a plug that will be wedged into a hole and glued or welded in place. Then runout isn't needed, but perhaps a simple position tolerance.
So in general, GD&T allows better product designs because it provides more tools in our toolbox. Without these tools, we may have a clunky design simply because the limited language of coordinate tolerancing didn't allow us to specify a requirement that better suits the function.
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
http://www.gdtseminars.com
RE: gd&t help provide better design
http://files.engineering.com/getfile.aspx?folder=4...
RE: gd&t help provide better design
Dave D.
www.qmsi.ca
RE: gd&t help provide better design
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: gd&t help provide better design
High quality fabrication drawings enhance design quality. If the fabrication drawings are prepared sloppily, the designer has not thought through tolerances. The parts can be hard to manufacture. The drawings can be bad enough that fabricators do not take tolerances seriously. There could be all sorts of assembly and functionality problems not observed by the designer.
A competent designer has a basic understanding of the fabrication processes, the assembly processes and the final end use of the product. GD&T is a language which allows the designer to specify exactly what is required from the fabricators. Since the language is based on standards, there is a mutual understanding of what the drawing means.
GD&T is not everything the designer needs to know, but metaphorically, it is a link in a chain.
--
JHG
RE: gd&t help provide better design
Jim Sykes, P.Eng, GDTP-S
Profile Services www.profileservices.ca
TecEase, Inc. www.tec-ease.com
RE: gd&t help provide better design