How Can We Help?
This real case shows why the Level you pick is everything — and how two rules that look
identical can behave differently.
The setup
A door with a sidelite on both sides. A machining notch must be cut on the door’s
right edge. Four notch rules exist for this series. They are identical in every visible
way — same Rule Type (machining-on-shape), same Position (Right) — except the Level they were
authored at.
What happens
| Rule | Authored Level binds to… | Result |
|---|---|---|
| Rule 35 | the door shape (no coupler in context) | notch on the right edge ✓ correct |
| Rules 66 / 108 / 141 | a coupler context (the left coupler) | notch forced to the left edge ✗ wrong |
Why the side flips
When a notch rule ends up bound in a coupler’s context, the engine snaps the notch to that
coupler’s column — here, the left coupler. Rule 35 binds directly to the door shape, so no
coupler overrides it and the notch stays on the intended right edge. The three failing rules were
simply authored at a Level that sits under the coupler, so at build time the left coupler is in
context and wins.
When a notch rule ends up bound in a coupler’s context, the engine snaps the notch to that
coupler’s column — here, the left coupler. Rule 35 binds directly to the door shape, so no
coupler overrides it and the notch stays on the intended right edge. The three failing rules were
simply authored at a Level that sits under the coupler, so at build time the left coupler is in
context and wins.
The lesson (and the fix)
- Nothing is wrong with rule 35. The other three point at the wrong node.
- The fix is to author the three rules at the same Level as rule 35 — not to change rule 35,
and not to fight the symptom downstream. - General principle: when a machining or part rule lands on the wrong side, column or member,
check the Level first. The Level decides the node; the node decides the geometry.