Morning,

I have a model designed with multiple parts in the part file, they are separated by splits and not merging the models. The idea is interlocking pieces for a plastic housing. This is my first attempt at modeling for plastic parts and it has been an exercise in failure.

The feature tree is extensive and grouped as best I can. The "cover" build and features ( fillets, drafts, etc) are first, then the right side ( and it's mirror ), and so on.

I added the L&G features last.

If I roll the model back up through the tree, add a feature in the rollback state that touches the L&G, and then roll it forward, the Lip & Groove feature disappears. No error, no warning, no "hey, don't do that", just gone.

Is the L&G tool that fragile? Is the modeling strategy for L&G features do them absolutely last?