NX6 Part Families for hardware. When do you have too many instances?

[apekim]

I have been generating part families for standard hardware for some time now. My questions is: At what point does too many instances start to drag down the system or efficiency? (See the example below)

Example: I needed to model a part family of machine screws. So I started with the cross recess pan head screws based on the NAS or MIL specs. For these there were about 150 different sizes and lengths for the CRES material and another 150 for the Black oxide finish. About 300 total so far. So now I need to decide if I should include the slotted pan head screws in the same part family or create a new one. Also, there are countersink screws with different head angles , etc.

I would like to know what others have done. Eventually, these part families will be stored in Teamcenter UA (which we do not have yet), so I am not sure if there are any drawbacks here as well.

Thx, Mike

 

[JohnRBaker]

There's really no drawback as to whether you have one Part Family consisting of 300 members or two separate ones of 150 each, at least from the system and data points of view. However, if you try to make a single master part family model represent different geometric styles, the models themselves would become more complex than they need to be. My rule was when it comes to fasteners (and I've modeled well over 100 different Fastener Part Families), to create a new part for each basic head style. So for example, in the case of at least the ANSI Metric standard, I created THREE different Pan Head screws, 'Slotted', 'Type1' (AKA, Phillips-Head) and 'Type3' (AKA, Square-Drive). I did the exact same thing for Oval Head style. Granted, I could have consolidated them all into one using suppress by expression the various driver style, but why make life more complicated than it needs to be.

Now if we're talking about different materials, then including them in the same file would be OK since that's just attribute and density difference, the geometry is the same.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

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