How to Use Propagate Edges in BricsCAD BIM

Quick answer: BIMPROPAGATEEDGES, one of the five Propagate flavors covered on this hub’s general Propagate page, copies a detail along the edge of a planar solid, a wall cap, gutter, railing, or border, for example.

The Starting Situation

Consider a one-story building with a flat roof. A vertical section through it shows where a wall and the roof slab meet. Model a capping detail on top of just one wall, either with direct modeling tools or by inserting and exploding a block from elsewhere.

Propagating the Wall Cap

1. Deactivate the section and launch BIMPROPAGATEEDGES.
2. You’re prompted to select the planar reference solid the edge detail relates to; select the wall the capping was modeled on and press Enter.
3. You’re prompted to select detail objects, solids or faces parallel to an edge of the reference solid; select the objects making up the capping and press Enter.
4. You’re prompted to accept: Yes, No, Inflate first, Save detail, or save detail to Library. Inflating isn’t needed here (see this hub’s general Propagate page for more on that option). Press Enter to accept.
5. A prompt specific to this variant follows: “Propagated to edges with similar orientation only?” Choosing Yes applies the detail only to edges with a similar orientation, in this case, wall edges that point upward specifically. Press Enter to accept Yes.
6. Another edges-specific prompt: “Choose location of detail relative to edge: Outside reference solid or Inside reference solid.” This controls whether the detail sits inside or outside (on top of) the base solids, placed inside, the detail subtracts from the base solids instead.
7. BIMPROPAGATEEDGES scans the entire drawing for similar locations; the view zooms out to show every suggestion, each with a widget, the same icon system covered on the general Propagate page. Since the wall cap was only modeled locally, a question mark widget here reveals “Location of original detail. Click to replace original detail by adapted extrusion,” click it to turn it into a green checkmark, replacing the original with an extrusion covering the full wall length.
8. Press Enter to complete the command; all four walls now have the wall cap, with corner connections created automatically.

Frequently Asked Questions

What does the “similar orientation only” option actually filter? Whether the detail applies only to edges facing the same direction as your original reference edge, wall edges pointing upward specifically, in this example.

What’s the difference between placing a detail inside versus outside the reference solid? Outside places it on top of the base solids; inside subtracts it from them instead.

Does BIMPROPAGATEEDGES handle corners automatically when propagating something like a wall cap? Yes, corner connections between propagated wall caps are created automatically.

Are these orientation and inside/outside prompts unique to BIMPROPAGATEEDGES? Yes, they don’t appear in the Planar or Linear Propagate worked examples covered elsewhere in this hub.