Joint line to polyline in Sketchup

How to join lines into a single solid line (polyline) in SketchUp.

Since SketchUp 2021 you no longer need an extension for this: “Weld Edges” is built into SketchUp — select the connected edges, right‑click, and choose Weld Edges to fuse them into one Curve entity (SketchUp’s equivalent of a polyline). The older Weld extension still works and is what the video below uses, but the native command does the same job.

Video tutorial:

Steps by steps :

• Select the lines you want to joint
• Select weld multi edges to polyline to join the polyline (or right‑click > Weld Edges in SketchUp 2021 and later)

Things worth knowing:

• The edges must actually share endpoints (be connected end‑to‑end). Weld will silently refuse to join a stray segment that only crosses or touches another line without a shared vertex — if a weld “didn’t work,” that gap is almost always why.
• A welded curve only obeys ONE radius when you Scale or soften it, and SketchUp will not let an edge belong to two different welded curves — if branching paths fail to weld, split them into separate selections first.
• Welding is the trick that makes Follow Me work in a single click: with a loose set of segments you’d have to pre‑select every edge of the path, but a welded curve counts as one path, so you just pick the curve and the face. The same applies to making a clean profile for Push/Pull or a smooth loop for “Add Detail.”
• A welded Curve is still just edges — it carries no face. Welding is purely a grouping/selection convenience, and you can always Explode the curve to get the individual segments back if you need to edit one of them.
• By default there is no keyboard shortcut for native Weld Edges; if you use it constantly, assign one under Preferences > Shortcuts (search “Weld”).