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drawing BOM vs engineering/ commercial BOM

stvnvl_8501stvnvl_8501 Member Posts: 88 PRO

I'm heavily relying on configurations in assemblies (different but similar frame structures). 
it uses a lot of subassemblies (sadly) to link parts together and to relate for instance the number of bolts to a specific beam element, basically adding one more "beam- with-bolts" assembly adds the correct number of bolts to the final count.
I have now 2 questions: 

first question: 
having configured parts or subassemblies packed in another assembly (for the abovementioned "logistic" reason) requires that assembly agian to be configured if I want to control the configurations of all seperate (basic) parts from the very top-assembly, as configuration-variables can only be used at the level of the assembly you are working in. This is really time consuming and error prone especially with assemblies going deep in levels, is their another way to do so?  

second question: sometimes my (CAD)BOMs end up differently than I want them to look in the drawing (engineering or commercial BOM) .  --> commercially we "kit" several parts in 1 box/ bag/ set. this isn't neccessarily (even rarely) reflected in how the CAD model is built up. is there a way to "group" parts in the BOM--> grouping them in 1  assembly and setting the assembly to not display its parts is not possible (because of the parts being allready in different assemblies as forementioned)
To use the example of the bolts. bolts are on the very basic level joined with a single beam. (eg a bolt for every hole in the beam)  but few levels up I need to display the bolts as sets of 4 bolts. (and sometimes the beam is allready part of an assembled" frame, and of no relevance as a seperate piece to display in the BOM ( to keep things simple ;-))  
 Manually adding is not an option as this defeats the purpose of setting up such an elaborate configurator. 

In short: is there an easy way to manipulate the structure of the BOM and keeping reference to changing occurance of parts and their quantities. 

thanks in advance. 


  • S1monS1mon Member Posts: 2,104 PRO
    edited May 25
    I'm not sure if this is exactly what you're asking for, but at my company, we have assemblies which are useful for CAD, but don't exist in the real world. For example, our scooter has a kickstand subassembly which is mounted to the chassis with two screws. When we order the kickstand assembly as a spare part it does not come with the mounting screws, and while it's being built, the mounting screws are not captive or anything like that, but still for CAD it's convenient to have the mounting screws with the kickstand. On a more complex example, our chassis assembly has covers and other parts which are really assembled during the final steps. In both of these cases what we ended up doing is making another layer of assemblies.

    Here's the structure of the Kickstand "Kit":

    In the properties we set the BOM behavior to "Show components only"

    At the next assembly level, the structure shows the kit, but the BOM shows just the Kickstand Assembly and the two screws.

    It's been a little extra work, but it means less work with adding mates when we place these "kits" in higher level assemblies. It also means that we can look at a lot of interactions at the "kit" level (in CAD) without needing to look at the higher level. The kits also do not have part numbers.
  • stvnvl_8501stvnvl_8501 Member Posts: 88 PRO
    Thanks S1mon, 

    This is indeed the method I also used for most of the "kits" we use. But this proves to be very complex and doesn't offer a solution to the following example (simplified for explanation) 
    a beam with several bolts. these beams are then assembled in a frame. 
    The assembled frame and the seratate bolts should then be shown on the BOM.
    In the above mentionend logic I would make the frame with the beams. and then on a higher level add all bolts separately.
    this would imply  a lot more work (and chance for error).
    Also, with each occurence of a beam, the number of bolts should add up. I haven't found a way to make this happen if the bolts and  beam aren't in a seperate subassembly. So essentially, I would need to "regroup" parts from a flat parts to a totally different structure.



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