Stepped Extrudes

Use Stepped profile to build a stack of bands as a single extrude. Select a region, press E, and turn the switch on in the extrude popover. A foot that steps in twice on its way down, a boss with a shoulder, a chamfered plinth: each of those is three extrudes and two booleans if you build it any other way.

How the bands stack

Turn the switch on and the extrude stops being a prism. Instead it lofts through a ladder of sections, each one described by two numbers:

Both numbers are relative to the previous band, not absolute. The heights add up as you go, and so do the offsets, so a ladder of three 2 mm rises reaches 6 mm and three −1 mm offsets have pulled the outline in by 3 mm. The base band is fixed. It is the sketch's own loop, listed as a read-only row so the ladder reads from the ground up.

Add as many bands as the shape needs. Every field takes a parameter or an expression, like any other number in Kapy, which is what makes a stepped foot resizable rather than redrawn.

What it takes over

A stepped extrude ignores most of the rest of the popover, and it does so quietly. The Distance field is replaced by a note, and Twist is disabled while the switch is on. Direction and end condition drop out of the picture too, because the ladder decides the height and leaves them nothing to decide.

A stepped extrude also always grows along the sketch plane's own normal. For a sketch on a world plane that is the same direction an ordinary extrude would take. For a subtract on a face sketch it is not: a plain cut runs into the material, and a stepped one does not turn around. Build stepped shapes as additions, and cut with them only after you have checked which way they went.

See also

• Extrude and Cut: the fields a stepped profile replaces
• Twisted Extrudes: the control it disables
• Loft: blending between sections you draw yourself