Revolve

Turning a closed profile about an axis instead of pushing it along the sketch plane's normal. It is how a round part is made: a shaft, a knob, a bottle, a pulley, a groove all the way round something.

Press Revolve… in the Timeline, or Q, and the command dialog opens over the viewport. The sketch stays live under it: clicking a region picks a profile, and clicking a line picks the axis.

Fields

Field	Notes
Profiles	How many closed regions turn. Click one in the sketch to pick it, click again to drop it, All to go back to every region
Axis	Sketch X, Sketch Y, or any line in the sketch, picked by clicking it or off the buttons under the row
Angle	Degrees. 360 is a full turn. Expressions and parameters both work
Profile offset	Grows the shape being turned this far all round before it sweeps, exactly as it does for an extrude
Direction	Base sketches only: which way out of the sketch plane the turn goes
Operation	Join, Cut, Intersect, or New body, on a sketch that sits on a face

The axis is a line, not an arrow

Which end of a line you drew it from does not matter. The direction is worked out against the profile, so picking a line that runs downwards gives exactly the same solid as picking one that runs up.

A profile lying across its axis is refused: turning it would sweep it through itself, and no amount of tolerance makes that a solid.

It follows the line

When the axis is a line in the sketch, what is stored is the line, not where the line was. Constrain that line to move and the turn moves with it: make a plate taller and a turn about its top edge turns about wherever that edge now is.

The two sketch axes are stored as themselves and never move.

Which way a turn goes

On a base sketch the direction is yours: One way or The other, out of the sketch plane either way.

On a sketch that sits on a face, the operation decides, exactly as it does for an extrude. A cut turns into the material behind the face; everything else turns out of it. There is nothing to choose, because there is only one answer that carves anything.

What a turn will not fold into a body

A turn standing on its own does everything: a whole turn, a profile touching its axis, a profile with a hole in it. Those are what a base sketch is for, and they are most of what a revolve is asked to do.

WARNING

Folding a turn into a body that already exists is narrower, and the dialog says so:

• It must stand clear of its axis. A profile touching the axis turns into a surface that closes to a line, which the modelling step cannot take as an operand.
• It must stop short of half a turn. At half a turn the far end lands back in the face it was sketched on, and past that it comes back out of the material and reaches nothing new.
• Its profile must have no holes. The island's wall and the pocket's wall would be the same surface rather than two that meet.

Each of these is a refusal with a sentence, not a wrong solid.

The way round all three is to turn the shape as a New body and then combine it, which has none of the restrictions.

Faces a turn makes have names

Every wall a turn sweeps is named by the sketch curve that swept it, as an extrude's wall is, and a partial turn's two ends are named as its ends. So a revolved face can host a sketch, take a blend, and be traced like any other.

See also

• Extrude, for the other way to make a solid out of the same sketch
• Turn a shaft, for the walkthrough
• Pattern, for repeating a body rather than sweeping a profile
• Timeline, for the row a turn adds and the angle it shows
• Profiles, for what counts as a closed region