Making solid STL from SW assembly

I made this assembly comprised of a left & (mirrored) pipe part files, orientated them a prescribed way & added some bridge elements. Like a plastic model sprue tree. So of course the mates between parts are like zero dimension gaps. When I did a file save as .STL of the assembly, I crossed my fingers that it might magically see it as one solid body & weld them together, but alas No. It makes a corresponding series of separate STL part files which kind of defeats the purpose of the orientated bridged assembly.

Any recommendations how to solve this issue? I don’t have much of any 3DP experience. I see what looks to be complex 3DP objects like a bearing with the balls in the races. But maybe that ‘works’ because they are indeed separate parts? I’m not aware of a way in SW to make a Boolean solid from an assembly like the way we can choose to join new body elements within parts files. If SW could somehow make a solid body assembly this way, I’m sure converting to STL would be straightforward. Thanks for any suggestions.
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Hello Pertertha, for a single file you could Save your SLDASM as a SLDPRT. Then saveas a STL. (it will likely have the 5 bodies but will be a single STL.
Also, try if you can “Combine” the 5 bodies into 1 and saveas a STL.

In the slicer I use (bambulab), if you import all of the bodies at once, it will locate them as they were in the assembly.

(Having said that, I am usually importing from a multi-body part, not an assembly. I’m not sure if that will make a difference.)

You actually want them to print as one combined piece, right? Unless you have a way to combine in the slicer/post-processor, the only way is per zxys001’s suggestion - Save assembly as part, then use Combine feature or some small extrude features to combine all the bodies into a single one before saving as STL.

Thanks! (hopefully). It never would have occurred to me to save an assembly as a part. Yet another thing I have not done in SW but probably should have been aware of. I check selected ‘preserve geometry references’ just as guess insurance. If all the components are defined/mated in the assembly, is this doing anything specific? Or maybe a better question: what exactly does checking this do?
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This should be a good explanation for you mate!

https://www.goengineer.com/blog/solidworks-save-assembly-part-preserve-geometry-references