Coincident Relation
The Coincident relation makes two pieces meet at their ends, or makes points sit exactly on top of each other, and keeps them joined as the sketch changes.
When to Use It
- Close a corner where two lines meet
- Join the end of a line to the end of an arc
- Pin a point or a line end to the origin
Step by Step
- Open a sketch and draw the pieces (see Lines, Circles and Rectangles). Sketching is part of modeling, which comes with the Pro plans.
- Click Select on the Sketch tab (or press S).
- Click the first piece, then click the second piece. Or click the dots (ends, corners, centers) of two or more points.
- Keep the pointer still for about half a second. A bar titled Add a relation to the N selected opens beside it, with one button for each relation that fits. Click Coincident. Instead of waiting for the bar, you can right-click the selection and choose Coincident under Make them, or click Coincident under Add a relation in the Properties panel. With only points picked, use the bar or Properties.
- A small green square marks the relation on the sketch, and a message says Coincident added. It stays true as you move and resize; Edit, Constraints lists it. Ctrl+Z takes it back.
Options
| Setting | What it does |
|---|---|
| Two pieces | Two lines, arcs or open outlines. The nearest pair of ends meet: the second piece's end moves onto the first piece's end. Circles have no ends, so pick the center point of a circle instead. |
| Two or more points | Move the pointer over a piece until its dots show, then click a dot. Each point after the first moves onto the first. The origin is a dot too, so you can join a corner to it. |
| Which one gives | The held piece stays and the other moves (see The Anchor Rule on the Relations page). |
| Also called Coincident | A point and a line (see Point on Line Relation) and a point and a circle or arc (see Point on Circle Relation). |
| Listed as | Coincident for ends and points. |
| Automatic | With Add relations while drawing on, snapping a new line's end to another end, or to the origin, ties it there for you. |
Tips
- Joined ends are what let lines and arcs close into an outline that Extrude and Cut can use.
- The Node tool can also pick two points: click one, hold Shift and click the second, then hold still for the bar (see Node).
- For points, use the bar or the Properties panel. The right-click menu needs a piece selected.
If Something Goes Wrong
- "Coincident cannot hold together with the relations already there. Nothing changed." Something already placed (another relation, a typed size or a Fix) fights this one. Delete the one in the way from the list under Edit (see Edit Menu) and try again.
- "Coincident already holds through the relations you have, so nothing was added." The sketch already forces this, so nothing more is needed.
- The button is not in the bar. The bar only lists relations that fit what you picked. Check what is selected in the Selected list of the Properties panel. If the panel says None fits this selection. Pick another point, piece or part edge with it., change the picks.
- "Coincident applied once: the relation solver could not load, so it will not be kept." The piece moved once but nothing was stored. Check your connection and add it again.
- "Coincident applied once. A combined outline cannot hold a relation; Break apart first to keep it true." A combined outline or a damaged arc cannot keep the relation. Right-click and choose Break apart, then add it again.