Magic Numbers in Parametric Software

Inventor doesn't have as good a Beta testing program.

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One trick that utilizes this is to put your BIG assembly into another assembly, then mate whatever parts/subs to it and then drag those parts/subs into the BIG assembly, save the big assembly and then just shut down the dummy assembly.

I think everyone has seen something like it, but there is no magic number. The mate solve time probably increases approximately exponentially with the number of mates, with different increases for each mate because of different situations for each mate. Stictly speaking, it probably should blow up sooner, but the mate solver allows for a lot redundancy in the constraints as long as each redundant constraint solves the same geometrically. That is, more than one mate con constrain the same degree of freedom. The solver has to figure out that this conflict is actually ok and not blow up. When it does blow up, it usually has to do with the solver algorithm not being able to figure out what to do with all the redundancies.

The only way to combat this is to limit the number of mates and redundant constraints. Use the subassemblies (they have other advantages too), and try to constrain only the degrees of freedom that you need to. One other thing to look out for is mating to less robust entities, such as edges. Esprecially if there are in-context relations involved. That is a no-no, and causes blow-ups and other entertaining behavior very quickly. Proper skeleton modeling techniques also help. You can look that up on the subscription site.

Why is it so complicated? Because SW gives you a lot of rope to hang yourself with.

Doesn't that eventually end up in nightmware rebuild times for the BIG assembly and any drawing views that show it?

Yup. I never tried dummy assembly with a drawing. Might be something to try.

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This would wreak havoc on PDM. Supposedly a detached drawing would stop the rebuilding and solving too.