When I read your inquiry, I flagged the same statement that ckurre mentioned.
My method is similar to swalton.
Let me add this not yet mentioned:
I make an assembly of the kind of bolt set needed (øhb#_hn, øhb#_fw_hn, etc.) and use it throughout the top level assembly where it fits. That reduces the number of parts in the top level assembly, as well as allows reuse of existing parts (subassemblies). Placing this way requires only one INSERT Constraint per bolt hole, then array as needed. The main difference between these bolt assemblies is bolt length (if the hole is the same ø and the thru thickness is different by more than 1/4"), and if the bolt diameter is different.
But the placement process is tedious and takes a long time at the end of the design process. If I keep a running record of holes, it's much easier. Otherwise, I have to manually look at every connection and thickness to decides ø + length + washers/nuts/etc. Then make assemblies out of all of them.
Someone long ago had an iLogic program that automatically populated fasteners of the same kind, but I can't recall who had it. Maybe on Autodesk's Inventor Store? https://apps.autodesk.com/INVNTOR/en/Home/Index
If I was better at iLogic, I would make a small Rule that works like the DesignAccelerator BoltedConnections (which I don't use b/c it has too many defects), except it would be much simpler and work on existing holes. I would expect this SHOULD BE part of Inventor already.
Incidentally, AutoDrop never worked for me, b/c it never picked the correct ø which forced me to do more mouse clicks to get one bolt assembly placed. My method of creating a bolt assembly on disk with iMates was as fast a solution as I could create.
... Chris
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