Drawing Views That Won't Update After a Design Change
A mechanical designer has produced a multi-sheet drawing from a bracket assembly. Sheet 1 has a base view, a projected side view, and a section view through the mounting holes. Sheet 2 has an exploded isometric with balloons and a parts list. After the designer increases a hole diameter in the model from 8 mm to 10 mm, the section view still shows the old hole size, while the base view updates correctly. The parts list on Sheet 2 still lists the old quantity for a fastener that was removed. The drawing was last saved before the model change. The designer needs to issue the drawing for manufacturing review.
1. Explain why the base view updated but the section view did not, and outline the steps to bring the drawing into a consistent state.
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Views update independently, and a section view depends on both the model geometry and the section line and its associated cutting plane in the parent view. If the section line was placed before the change and the parent view updated, the section view can retain stale geometry until it is explicitly refreshed or its section line is re-associated. Cached drawing state from before the model change can also persist until the document is updated.
Steps to reconcile:
- Use Update / refresh on the drawing to force all views to re-evaluate against the current model.
- Open the section view and check that its section line still references the correct parent view and passes through the resized holes.
- If the section line no longer intersects the holes correctly, edit or redraw it.
- Verify the section view shows 10 mm holes; if not, delete and recreate the view.
- Check that no view is set to a manual/frozen state that suppresses updates.
The judgement is that drawings are derived but not automatically consistent; the designer must verify each dependent view, especially sections and details, after model edits.
2. The parts list still shows the removed fastener. What should the designer check and do before issuing the drawing?
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The parts list is generated from the assembly's component structure and its item properties, so a stale row usually means the list has not been refreshed or the component removal did not propagate to the drawing's referenced model state.
Checks and actions:
- Confirm in the model browser that the fastener component was actually deleted, not just hidden - hidden components still appear in parts lists.
- Refresh or re-create the parts list so it re-reads the current assembly structure.
- Verify item numbers and balloon leaders on Sheet 2 still point to existing components; orphaned balloons indicate a stale list.
- Check that quantities reflect the current instance count.
- Re-check the exploded view, since removing a component can leave the explode distance or balloon placement referencing a missing part.
The judgement: a parts list is a report on the model, not a static table. Before release, the designer must confirm the drawing's data reflects the current assembly, and must distinguish "hidden" from "deleted" - a common source of phantom BOM rows.