System information

SolveSpace version: 3.0~060a3280

Operating system: Debian Buster

Expected behavior

Three models, A, B, and C.

• A ("syringe plunger") is "the environment" - the thing I'm attaching to, so not part of what I'm making.
• B ("carriage plunger part") is the part that interacts with the environment.
• C ("carriage") was to be the overall part. C includes B, and B includes A but suppresses from the solid. I'd expect to see the solids of B in C.

Actual behavior

A in B looks right - I only see the lines, not the solid, or "part A"

B shows up in C as wireframe-only as if it were also "suppress from the solid".

Here are the files:

testcase.zip

Additional information

I did note a weird drawing of "chords" in the face of the cylindrical part of my model B ("carriage plunger part") so I fear it might be slightly numerically unstable or something. Just backed up a single extrude group to see it:

I tried making a minimal repro and it didn't show the issue... Not sure why since I made all of these this morning using the same build (and actually, the same execution) of SolveSpace.

Here are my sample files that do not show the problem, presumably there's some subtle difference between them and my "real" models I didn't identify. Maybe the same thing causing the "chords" ? I did end up having to turn to trimeshed instead of nurbs fairly early ("g007-extrude" of "g006-top-pocket", essentially my second sketch) because apparently adjacent curved faces aren't a lot of fun for the nurbs engine, even with slightly different diameters.

these-work-fine.zip