Clash Detective
Clash Detective finds where models collide. Learn to set up focused tests, filter out noise with tolerances and rules, group results into real issues and report them.
In this lesson you will
- Set up clash tests between search sets
- Choose clash types and tolerances
- Group, review and assign results
- Report and track clashes over time
Setting up a test
- 1Home › Clash Detective › Add Test; name it STR Beams vs MECH Ducts.
- 2In Select, choose the search set on the left (Selection A) and the right (Selection B).
- 3Choose Type: Hard, Hard (Conservative), Clearance or Duplicates.
- 4Set Tolerance (e.g. 25 mm) so tiny overlaps are ignored.
- 5Run the test.
Clash types
Hard: geometry intersects. Clearance: objects are closer than the tolerance — e.g. keep 50 mm around cable trays. Duplicates: identical objects in the same place (often double-modelled elements). Choose per test according to the clash matrix.
Rules
Rules ignore clashes you don't care about: items in the same layer or file, items in the same composite object, or items with matching properties (e.g. pipes and their insulation). Good rules cut false positives dramatically.
Results
Each clash has a status: New, Active, Reviewed, Approved, Resolved. Group related clashes (e.g. one duct hitting ten beams) into a single issue, assign it to a person, add comments and a viewpoint. After models are updated and the test re-run, fixed clashes become Resolved automatically.
Reports
Report creates HTML, XML or viewpoint reports for each test, with images, locations and status. Share grouped issues rather than raw counts, and track numbers per test over time to show progress.
Quick reference
| Command / tool | How to start it | What it does |
|---|---|---|
| Clash Detective | Home tab | Clash testing (Manage) |
| Rules | Clash Detective | Ignore unwanted clashes |
| Group | Results tab | Groups clashes into issues |
| Report | Clash Detective | Exports clash reports |
Common mistakes
Thousands of clashes between pipes and their insulation.
Add a rule to ignore items in the same composite or with matching system.
Everything tested against everything.
Use a clash matrix and focused tests.
Exercise
Run a clash round
- Create three tests from your search sets with appropriate types and tolerances.
- Add rules to remove false positives.
- Group results into no more than ten issues and assign them.
- Export an HTML report.
You should end up with: An actionable clash report.
Checklist
0 of 5 checked · saved on this device
Lesson quiz
Which clash type checks for a minimum gap?
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