Best workflow for using motion study in an assembly???

Hello fellow SW users!

I have a problem that has alluded me for some time and finally want to solve it...

I generally make my assemblies from an assembly file and create new parts by adding new parts directly in the assembly file... easy enough.

These new parts are created with InPlace mates and become fixed in place and are fully defined.

I now want to create a motion study to test some of the moving parts. In the past I would create a new assembly file, import all the parts, and add new mates that allow me to move the parts... but this can sometimes be alot of work keeping the two files in sync.

I am sure there is an easy way to do this in the original assembly file? The problem is all the inplace mates are keeping my parts from being able to move in the motion study. I would think by creating a new configuration and then supressing all the mates, that would be best, but sometimes I get errors... any workflow ideas out there?

thanks!

SolidworksAssemblies