Recommended way to show alternate positions of a component

[DLH81]

I'm just wondering what is the recommended method of showing alternate configurations or positions of a component. For example, if I have a seal that has a free state and the installed (compressed) state, how would it be best to have both the free state model available to create the drawing and the compressed state model available to use in the assembly model? I have controlled this with reference sets in the past, but is that still the best approach? Could arrangements be used in this case?

Also interested in the case of a wiring harness that moves depending on the assembly position and if this would be the same situation as the seal example above. In the case of the wiring harness the drawing is not based off the model definition.

Running NX8.0

 

[JohnRBaker]

For alternate positioning of Components in, as well as alternate CONTENT of, Sub-Assemblies, Arrangements is the recommended approach to take. However, if your specific need includes flexible objects, such as springs, latches/catches or parts that conform, at least in part, to the shape of the part they are 'mated' to, then you should also look at Deformable Parts.

As for Wiring harnesses or other 'routed' systems, like hoses and tubing, you should really look at the specific application products Siemens' offers since they provide specific solutions for these types of designs, including some that provide specialized Drafting and Manufacturing needs such as 'form-boards' for assemblying wire bundles, and BOM/'Cut Lists' for piping and tubing configurations.

For more information about the various NX mechanical routing products, please go to:

http://www.plm.automation.siemens.c...l Routing - NX Fact Sheet - 4181&docType=.pdf

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[cowski]

Arrangements are the preferred way to show multiple component locations in a single assembly. If you have an assembly of a car, you could save the door open and door closed arrangements in the same assembly and generate drawing views of each. In your seal example, if your drawing file is separate from your assembly file, the use of reference sets would be the easier method.

If your seal can take on multiple 'assembled' states or you are dealing with a component that can take on a range of values (such as installed length of a compression spring), then a deformable component may be the way to go. They take more TLC in setup and use, but may save you time in the long run.

www.nxjournaling.com

 

[DLH81]

Thanks. Does that mean that reference sets are no longer recommended for any application? Just curious if there is an example of when the use of reference sets is encouraged?

 

[DLH81]

Oops, cowski was probably replying as I typed that last message. That helps clear things up.

 

[JohnRBaker]

The primary purpose of Reference Sets are to provide a means by which, when working in a detailed part, that the geometry, generally a single Solid body, is part of the 'Model' Reference Set while of of the other geometry, which may have been used or referenced while defining the final model, is not included. This other geometry could include Datums, Points, non-sketch Curves, Sketches which were not made internal to the Model's feaures, Sheet Bodies used to trim or provide shape to the final model, etc. These items generally serve no real purpose when the Part Model is added as a Component to an Assembly and therefore the system, by default will use the 'Model' Reference Set which only contains that final Solid body. Now at any time, you can replace the 'Model' Reference Set with ther 'Entire Part' Referense Set if some of the 'extra' items are needed, perhaps a Datum or a Point needed to help position or constrain the Component, but once properly constrained, the Component can be set back to the 'Model' Reference Set without losing any links to the referenced, albeit no longer visible, items NOT in the 'Model' Reference Set. As such, this is how Reference Sets are recommended to be used, in the detail peice parts and NOT to control the content of an Assembly. While there is technically nothing preventing you from using a Reference Set in an Assembly to control which Components to include when using the Assembly as a Sub-Assembly in a higher level Assembly, it can cause problems later on when it starts to act like a 'filter' causing lower level Components from NOT being loaded when the top-level Assembly is opened.

So the rule of thumb is; for piece parts, use Reference Sets to control the content of what what is considered to make-up the Component when placed in an Assembly (if you do nothing, out-of-the-box this is the way Reference Sets will automatically behave). And for Assemblies, which will be used as a Sub-Assembly in a higher level Assembly where some of its components need to be seen in different positions or with different content in the current Assembly, then the use of Arrangements is recommended.

The bottom line is that you will need to be aware of both Reference Sets and Arrangements, but normally you can almost ignore having to worry about Reference Sets since they generally behave exactly the way you expect them to without having to do much work. Arrangements take a bit more effort but are very well behaved once you learn how and when to use them.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.