BOM (Assembly) columns multiplication

[ABHUT_9090]

Hello everyone,

I need to multiply  item qty and SQ_INCH column to get TOTAL_SQ_INCH. I need help with ilogic code to get this output.

Thank you.

[SBix26]

Inventor iLogic, API & VBA Forum

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Sam B

Inventor Pro 2023.0.1 | Windows 10 Home 21H2

[johnsonshiue]

Hi! Sam is right. This requires an iLogic rule. The way BOM handles property expression is purely text-based. IT does not involve any math.

Please take a look at an old thread. The expert users share some apps and an iLogic rule.

https://forums.autodesk.com/t5/inventor-forum/part-assembly-quantities/td-p/4342976

Many thanks!

[pcrawley]

It is achievable with iLogic, but the result would be so dangerous I'd strongly recommend not doing it.

If you calculate the TOTAL_SQ_INCH value based on the three instances of that part in the assembly, then push it to the part's iProperty, the result would be correct. 

In the next assembly you place four instances of the same part.  One of two BAD things will now happen:

1. You'll forget to run the iLogic and the the BOM shows TOTAL_SQ_INCH for 3 instances - which is incorrect because you placed 4 instances.
   
   
2. You'll remember to run the iLogic rule and update the TOTAL_SQ_INCH for 4 instances.  You just invalidated the first assembly which had 3 instances.

I would suggest doing calculations like that in the Parts List on the drawing using substitution & sum of values.