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Enter a sphere

Describes RotoSpider Desktop 0.8.13 · checked 2026-09-13 D5

A spherical tank or float is entered as a sphere with one measurement, its diameter. The builder needs nothing else, and the layout treats the mold as the ball it is rather than as the cube around it.

Entering a sphere

On the Mold Data tab, select the row, press Change Shape and pick Sphere. The builder opens with the Diameter field, filled in with the smallest of the row's three sizes, and the two views:

Build & Use puts the sphere on the row: its footprint is the diameter both ways and its height is the diameter. The trial's DEMO-M24 is an 800 mm sphere.

A sphere rests on the plate at a single point, so the builder assumes the mold's frame holds it there; the space the layout reserves is the ball plus the clearance around it. If the real mold sits in a cradle or on a ring that reaches wider than the ball, measure that and enter the mold as a cylinder or a tapered cylinder instead, since the cradle is what takes the room on the plate.

Why turning it changes nothing

For every other shape the layout tries the mold turned on the plate, in quarter turns for a plain box and in twelve steps of 30 degrees for a built or drawn shape, because a turned L or wedge may fit where the unturned one did not. A sphere is the same from every side, so the builder says so, "turning it changes nothing", and the layout does not try. Dragging a sphere in the scene to turn it does nothing either.

Where a sphere wins room

The ball's widest part is at its middle height. Two spheres side by side keep the clearance between their equators, and a box mold beside a sphere can come closer to it below and above the equator than a box could come to a box. On a crowded spider that is a hand's width per neighbour.

The other way round, a sphere is the shape that most often fails the rotation envelope on a small arm: its height equals its width, so a ball that fits on the plate may still reach past the envelope when the arm turns. The staging area's reason sentence says so when it happens; the page on the space a shaped mold needs explains the envelope check.