Single Drawing - Multiple Hole Configurations

[liegev]

Hey Guys,

In an effort to maintain fewer drawings I'm attempting to consolidate some sheet metal drawings. Two products have identical features except for one hole. In part X310-0063 there is hole and in X310-0064 there is not a hole.

I'm thinking of creating a drawing called X310-006X. My hope is that with this move I will be able to rev these two parts at the same time. This would in theory save me from potential errors in updating a feature in one part and not the other.

To give you an idea of what I'm working on, one of our products has a usb connector and the other does not, that is the only mechanical difference between the two.

So my question is: How would you call out this extra hole on a drawing and associate it to that part number?

Or talk me out of this. I could simply create an additional drawing for the other part and just update the two in parallel.

Thoughts?

 

[CheckerHater]

You are looking for what's known as "tabulated drawing".

The drawing contains table with part numbers and explanation how one number is different from the other.

As I am away from my desk right now, I am having hard time finding suitable illustration, but the general idea is pretty simple.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[ewh]

For such a simple difference, I would just add the part number to the hole callout, "X310-0063 ONLY".

"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

 

[CheckerHater]

Quite possible.

Still, somewhere on your drawing both numbers should be shown. Why not call this "somewhere" a "table"?

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[Tunalover]

I concur with ewh if that family of parts is not expected to grow. If the "family" of parts gets greater than two then I would go with the tabulated drawing per CheckerHater.

Tunalover

 

[CheckerHater]

I feel like I am missing something here.

Where does it say that tabulated drawing is created when quantity of part numbers is larger than 2?

Normally 2 part numbers are good enough (please see enclosed illustration).

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[liegev]

Good Morning,

CheckerHater, ewh, thank you for your insight. CheckerHater a special thanks for responding so quickly. I spent the weekend googling "tabulated drawing" and I think I'm there.

Let me start by stating that the "family" will definitively grow. I can expect a minimum of 6 products that will use this chassis with different hole configurations.

Allow me to ask just two quick follow up questions.

1. If I want a particular hole not to be machined, what would you guys put in the table in place of the dimension?

2. A "document control" question: I note a part number in my drawing, but not a drawing number. This has created a conflict with this tabulated drawing since it is not for a single part. I'm looking for a logical approach to naming a tabulated drawing. You guys have any examples?

Many thanks,
Charles.

 

[CheckerHater]

1. You can use "dash" or even have separate "hole absent/present" column in your table - there are no "chiseled in stone" rules

2. It's easy if you company's doc. control system allows for "dash numbers" - then you have drawing 12345 and parts 12345-001, 12345-002, 12345-003.
If not, you have to come up with something of your own.
Possible (but not the best) is assigning first part number in the table as drawing number.
Or you can create part number family using -a, -b, -c suffixes. As long as you document what you do, and users of the drawing can follow your idea, you should be OK

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[KENAT]

Alternative idea which may work better in systems not used to "-" numbers...

Have a base part number/drawing that has all the common features on it.

Have multiple higher level part numbers/drawings that call up the base part and then add the unique features at that level.

That way any changes to the lower level part get populated throughout the pack.

We've done this on a product recently (I'm not 100% convinced on our reasons for doing so but fundamentally from a config point of view it's a valid approach).

(Of course, if you're doing part number changes V revisions properly per ASME Y14.100 then shouldn't be much of an issue as parts to any revision will be fully interchangeable.)

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