JOIN

CompleteChecked against Musa CAD 0.8.0Verified Oct 23, 2026

Join collinear or connected objects into a single object.

Type: JOIN or J
On the ribbon: Home › Modify (slide-out) › Join
Since: Musa CAD 0.1.0

What it asks first

Command: JOIN
Select source object or multiple objects to join at once:

Read from Musa CAD 0.8.0 itself (musacad --dump-wiki-data), so these facts always match the release this wiki is built for (0.8.0).

JOIN turns several objects into one. A chain of lines and arcs becomes a single polyline that moves, offsets and selects as one object. Two pieces of a broken line become one line again.

How it works

The quickest way: select the objects first, then type J and press Enter. Musa CAD joins them at once.

Or type J and press Enter with nothing selected. Pick the source object, the one the result takes its layer and properties from. Then pick or window the objects to join to it, and press Enter.

Command: J
Select source object or multiple objects to join at once: (pick line 1)
Select objects to join: (pick lines 2, 3 and 4)
Select objects to join: Enter
4 objects joined into a polyline.

Before, on the left: in the top row, four separate lines numbered 1 to 4 form a path with a peak in the middle, with every end marked; in the bottom row, two lines numbered 1 and 2 lie on one line with a gap between them. After, on the right: the top row is one blue polyline of the same shape, and the bottom row is one blue line running from the far end of the first to the far end of the second, with no gap. — A chain becomes one polyline; two lines on one line become one line.

What JOIN makes

What you get depends on what you join.

You join	You get
Lines that all lie along one line	One line, from one far end to the other. Any gaps between them are filled. Musa CAD says, for example, `Joined 2 lines into one line.`
Arcs that all lie on one circle	One arc. The gaps between the arcs are filled, all but the largest one, which stays open. If they reach all the way round, a circle.
Elliptical arcs that all lie on one ellipse	One elliptical arc, filled in the same way, or a whole ellipse.
Splines of the same degree whose ends meet	One spline.
Lines, arcs and open polylines whose ends meet	One polyline. If the chain closes on itself, a closed polyline, and Musa CAD says `4 objects joined into a closed polyline.`

Options

Option	What it does
cLose (`L`)	Offered when the source is an arc or an elliptical arc: `Select arcs to join to source or [cLose]:`. Makes the source whole. Musa CAD says `Arc converted to a circle.` or `Elliptical arc converted to an ellipse.`
`Enter` at Select objects to join	Joins what is selected and ends the command.

Good to know

For a polyline, the ends must meet exactly. If none do, Musa CAD says JOIN: the selected objects don't share endpoints. Use object snaps when you draw, or close small gaps with PEDIT Multiple, Join, which asks for a fuzz distance.
JOIN needs at least two objects it can join, or it says JOIN: select at least two joinable objects (lines, arcs, open polylines).
Closed polylines have no free ends and are left as they are, as are objects JOIN cannot join, such as text.
If the selection holds several separate chains, each becomes its own polyline, for example Joined 6 objects into 2 polylines.
The new object takes the layer and properties of the source.
The whole join is one undo step.

Compared with AutoCAD

As in AutoCAD, lines on one line become one line, arcs on one circle become one arc, and a chain of mixed pieces becomes a polyline. JOIN itself has no fuzz distance; PEDIT’s Multiple Join has one, as in AutoCAD.

Edit the joined polyline’s vertices and width with PEDIT.
Offset the joined outline in one go with OFFSET.
Turn a polyline back into separate lines and arcs with EXPLODE.

Reading settings