Need some Clarification. We are doing a First Articl Inspection on some product from China (Don't start). Anyway, the parts are made of Nickel Plated Die Cast. There is a note in the drawing that says "ALL DIMENSIONS SHOWN FOR REFERENCE ONLY". However, there is a thread call out for a 3/8-32 UNEF-2A. The UNEF standard says the major diameter must fall between .3680/.3740. We are measuring .3632-.3670 The no-go gage threads onto these in some cases all the way! Even thought the print has that "Reference Only" comment, I believe since there is a UNEF call out on the print, the diameter should be within that specification. Am I wrong?? Your thoughts...:cool:

If the dimensions are for reference only why do they have to be there at all....?

It seems to me that the only thing really necessary would be an arrow pointing to a hole saying "Hole here"

However, because specific dimensions are given they should be heeded.

I don't think you're wrong.
The drawing is calling out a thread standard, not a dimension per se.
When you refer to the standard for that thread, it gives you a required dimension.
Therefore, by calling out the standard they are holding themselves to it.

True. My problem is I'm troubled over the note saying "Reference Only". The thread is referring to the standard, so I'm troubled by that. Have you seen this before?:(

True. My problem is I'm troubled over the note saying "Reference Only". The thread is referring to the standard, so I'm troubled by that. Have you seen this before?:(

Sure I've seen this. It's not an excuse to "do as thou wilt".
They say they make the thread to 3/8-32 UNEF-2A. That's what it needs to be, 'reference only' or no.

What does your purchase order say - does it specify the thread standard?
You can go back to that.

Usually drawings marked for “reference only” indicates that the dimensions in question must be verified before the level you are inspecting the part at. Since you state that this part is a “Nickel Plated Die Cast" there should be a lower level drawing stating the same dimensional requirements prior to the nickel plating.

The parts must conform to the dimensional requirements before the nickel plating which will change them because of the addition of the nickel. Now regarding your thread callout. If it still does not conform to the requirements for a 3/8-32 UNEF-2A after plating you have problem because threads may disengage from the mating part.

Need some Clarification. We are doing a First Articl Inspection on some product from China (Don't start). Anyway, the parts are made of Nickel Plated Die Cast. There is a note in the drawing that says "ALL DIMENSIONS SHOWN FOR REFERENCE ONLY". However, there is a thread call out for a 3/8-32 UNEF-2A. The UNEF standard says the major diameter must fall between .3680/.3740. We are measuring .3632-.3670 The no-go gage threads onto these in some cases all the way! Even thought the print has that "Reference Only" comment, I believe since there is a UNEF call out on the print, the diameter should be within that specification. Am I wrong?? Your thoughts...:cool:

Whose drawing is it? Why is the "reference" note there? What was the intention?

The 3/8-32 UNEF-2A should be verified prior to Nickel Plating. There should be a lower level drawing. The "referenced dimensions" would be prior to plating.