Drawing Philosophies (help!) 2

[evolDiesel]

Please look at the attached print and tell me if this is legal, and if so, legal by what standard (ASME Y14.100-2004 is what we use).

This part has a locating fixture for a jig (see right hand view)... after locating it, we face it off (see left hand view).

These have been 2 different part numbers... when the left one is built off the right one.

Recently I had an engineer come to me and suggest we could put both of these on one print using configurations (SWx) ... just as you see in the attached print.

What do you guys think of putting these 2 parts on one print? What is the official rule on having some views on a print not match up with other views (some of these views would not have the facing operation). Seems confusign to me.

 

[ringman]

Try Global Drafting manual

 

[fcsuper]

Here we "should" again... ASME Y14.5M-1994

"1.4(e) The drawing should define the part without specifying manufacturing methods. ... However, in those instances where manufacturing, processing, quality assurance, or environmental information is essential to the definition of the engineering requirements, it shall be specified on the drawing or in a document referenced on the drawing."

Even though ASME uses the word "should" on this requirement, the follow-up statement pretty much makes it an absolute rule with some expections. So, yeah, the standard says not to specify manufacturing processes on engineering drawings.

In my practice, these means to me that make-from drawings show the original make-from part as the material of the final part without going into details about how to get from one to the other. Just show the final condition expected with only the applicable defferences defined.

Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group

 

[evolDiesel]

From the feedback I'm getting... it sounds like the answer is "no, do not put both parts on the same drawing".

 

[ctopher]

evolDiesel,
I agree with that conclusion.

Chris
SolidWorks/PDMWorks 08 3.1
AutoCAD 06/08
ctopher's home (updated Jul 13, 2008)

 

[drawoh]

evolDiesel,

We have a CAD Admin guy who's mantra is "you can't dictate processes on a drawing" and he says he got it from DOD standards.

I agree with your CAD guy. This is like calling up the tap drill when you specify a tapped hole.

If the part is entirely machined or punched, I would not show or even aknowledge the unfaced version at all. Now, on the other hand, if the unfaced part is a casting or a weldment which gets clean-up machining, I would make a separate drawing, and I would make sure everybody worked off the same datums.

JHG

 

[dgallup]

Back in the day when we had separate Design & Manufacturing Engineering Departments we made the finished part drawing and threw it over the wall to let manufacturing figure it out. Now that I have to make both the part drawing and the operation sequence drawings I have a different opinion. We use Pro/E so it's "family table parts", not the SW "configurations" but similar concepts. What I do is have one drawing or spec for the raw material (bar stock, forging, casting, etc.) Then there is a separate drawing for the finished part. Secondary sheets for the finished part show the operation sequences with only the dimensions created at that step. So sheet one of drawing 123 shows all the finished part requirements. Sheet 2 shows part 123 op 010, sheet 3 shows part 123 op 020 etc. Each sheet only shows one configuration and the operation sequence number for that configuration. A secondary benefit of this procedure is that the process sheets are automatically updated if there is a change to the finished part.