CAD Forum

Sometimes a reference document is needed in an assembly — for example, a P&ID for a plumbing module — what is a good way to do it?

We see two approaches—

1. create a dummy (no geometry) sldprt file for the P&ID and insert it into the assembly. The “part” then shows up on the (parametric) BOM with a Qty of 1 — sometimes the engineer changes it to 0, since no physical copy of the document is needed.

This creates several issues: 1. Inconsistency, since it depends on whether the engineer chooses/remembers to change the qty; 2. If qty is manually changed, it breaks the parametric nature/beauty of SolidWorks; 3. One will need to set up the properties of the empty sldprt file, which then gets released… a bunch of silly actions to be honest;

2. manually add a row of text to the BOM table on the drawing. This naturally breaks the parametric nature, since the row does not correspond to a component in the assembly. Additionally, it (probably) doesn’t show up on the components list if the assembly in PDM, thus could cause data mismatches between PDM and ERP. Another issue is that, if the same document is used in two assemblies, the BOM tables might not agree with each other, since part number and description are manually typed in (hence possible human error).

Is there a better way?

You can set a property in a model to drive the BOM quantity. I think you could set that to 0 in your dummy part. The quantity has to be a number. (I really want to put A/R for all my things like Loctite, but no such luck.)

You can't put zero either, unfortunately. Well, I mean, you can, but if you do it will ignore it and just put the actual count. You can put 0.000001, and the BOM will show up as 1e-6... I haven't found a way to make it round to zero. :-D

You could select "User Specified Name" as part number displayed for BOM for the configuration of the dummy part that you are adding to that assembly.

Then use a name like "**REFERENCE ONLY** P&ID"

Then make sure that you only use this configuration in your dummy part.

Also, if you can't put a 0 quantity, then what does this setting mean?

DanPihlaja wrote: ↑Thu Jul 11, 2024 2:32 pm
Also, if you can't put a 0 quantity, then what does this setting mean?

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That setting only applies to multi-configuration BOMs where a part is suppressed in some configurations but not others.

The best way is to have the dummy part in the model. If your release process requires 'a bunch of silly actions', well, that's a problem with your process.

To get a zero in your quantity column, try this:

1. Add a custom property (Yes/No) to your reference documents. Call it something like IS_REF.
2. Set the property to 'Yes'.
3. Add a new column to your BOM (call it QTY (no trailing period) and set it to an equation:
   =IF(`IS_REF`="Yes";0;'QTY.')
4. Hide the original QTY. column

I haven't tested this extensively, but it seems to work.

JSculley wrote: ↑Thu Jul 11, 2024 3:52 pm That setting only applies to multi-configuration BOMs where a part is suppressed in some configurations but not others.

Ahh, thank you. Didn't know that.