I am at the sixth month point in a conversion from Inventor in SW. I'm running 2018 in Windows 10.

I frequently design by creating an envelope to represent my available space or general limitations. I'll start with a new assembly, then create a new part within to create the envelope. As my design progresses, I create new parts, typically placing the first sketch on a plane of the envelope and mating my sketch geometry to parts of the envelope, either with mates or dimensions or both. A lot of instances involve geometry converted from the envelope. I try to relate as much as possible to the envelope vs. part-to-part, so if my parameters change, I can simply modify my envelope and allow my parts to update. This was a common method for me in Inventor.

Up to this point, I have no issues performing the design work in SW. Where I'm running into difficulties, however, is when my design winds down and I start to determine which parts need to be grouped into sub-assemblies. I have tried pre-selecting the parts desired and RMB to select create new sub-assy. I have also tried to insert a new sub-assy and then drag the desired components into it in the tree. I have probably tried a few other things that escape me right now, based on my level of frustration.

It seems no matter how I tackle this portion, I'm get a list of errors and shattered assemblies or missing parts. I had one part today that warned me the geometry, which consisted of two lines that were converted from the envelope edges, was now invalid. It was the first sketch in the part and nothing would fix the lines, so the entire part was unrecoverable.

The most basic errors I am seeing revolve around the In-Place mates that were generated as these parts were created, based on my envelope. I also tend to lose a lot of mates in the sketches, i.e. my coincident points, collinear lines, dimensions to an edge on the envelope, etc.

Also, if I try to bring in a second copy of one of these parts or assemblies and mate it into position I'm having difficulties. If you have ASSY<1> and you bring in ASSY<2> and try to mate it to the first instance, it ALWAYS moves the first instance off of the envelope to align to the newly placed instance. Both parts then break and often disappear.

I swear I have to missing something simple. Any advice would be greatly appreciated!

Attachments: Capture 1 shows a new sub-assy I created, comprised of two instances of Part 1. Notice the signs, indicating it is not fully defined/mated.

Capture 2 shows the tree and what the part is.

Capture 3 is the part/tree prior to creating the new sub-assy. Notice how everything is happy and no minus signs...

Message was edited by: Mike Thompson Corrected a typo.

Message was edited by: Mike Thompson Added file of my model.