Fillet 3D Polyline

This command fillets two segments of a 3D polyline (or two un-joined 3D Polylines) with the given radius. AutoCAD's FILLET command does not support 3D Polyline entities. Since 3D polylines cannot have arcs, this command draws the fillet arc as a series of short chords. The elevations along the curve are interpolated from the 3D polyline.

There are two processing modes: corner and intersection. The corner mode works like the standard Fillet command except that it's in 3D. The intersection mode works at the intersection point between two 3D polylines. One polyline is set as the main polyline and the other as the side polyline. The main polyline is used for reference only and is not modified. The side polyline is modified to fit in the fillet radius. The intersection mode works for crossing and T intersections. An application of the intersection mode is for curb 3D polylines at road intersections.

Before and after fillet3d on the cornerBefore and after fillet3d at intersection

Prompts

Fillet corner of a polyline or intersection of two polylines [<Corner>/Intersection]? press Enter
Enter fillet radius <10.00>: press Enter
Select a corner point on polyline: pick 3D polyline near meeting point of two segments
Select a corner point on polyline: press Enter (to end command)

Pulldown Menu Location: 3D Data >  3D Polyline Utilities
Keyboard Command: fillet3d
Prerequisite: 3D polyline