Scripting API

Sprue spiral

from ArtisanPlugin.Scripting import ManufacturingApi as manufacturing

The spiral is the flat cousin of the helix tree: the same chain-printing idea, but the feed wire is coiled flat, standing on legs above the plate, and each link hangs from a single vertical connector below the wire. It keeps the whole batch low and shallow - useful when the flask or the printer’s build height is the constraint. This is the ArtisanSprueSpiral tool, headless.

Usage

ids = manufacturing.SprueSpiral(linkMeshId, basePoint = (0,0,0), copies = 0,
                                maxDiameter = 0, wireDiameter = 0,
                                connectorLength = 0, clearanceMargin = 0,
                                showBase = False)      # -> [ids]

Parameter	Default	Meaning
`linkMeshId`	required	The chain link to multiply - a mesh, or a SubD (meshed at default density)
`basePoint`	`(0,0,0)`	Centre of the spiral on the plate; the origin is the tool’s starting position
`copies`	`60`	How many copies of the link to hang from the wire
`maxDiameter`	`100`	The largest diameter the spiral may grow to, mm
`wireDiameter`	`3`	Diameter of the spiral feed wire, mm
`connectorLength`	`3.25`	Length of the vertical connector between wire and link, mm
`clearanceMargin`	`0`	Extra clearance added between neighbouring copies, mm
`showBase`	`False`	`True` adds the honeycomb base plate under the legs (off by default, like the tool)

Every numeric parameter follows the house 0-keeps-default convention: 0 means “use the tool’s default”. For clearanceMargin the default is 0, so a positive value simply spaces the copies out further. There is no -1 sentinel.

As with the helix, you do not set the turns, the turn spacing or the inner eye: like the tool’s Generate button, the layout is auto-sized so the requested copies fit within maxDiameter, with the link hung from its Y axis - the tool’s starting orientation. This is a long operation; the auto-sizing searches for a collision-free layout. A layout can be feasible yet carry a warning - typically that fewer copies than requested fit cleanly - in which case the call still succeeds and the warning is printed to the Rhino command line, prefixed Sprue Spiral:, exactly as the tool surfaces it.

SprueSpiral returns the ids of all the meshes it adds: the spiral itself plus one mesh per copy. Everything is baked to the last user layer with the wax colour, like the tool’s Accept; the source link object is left untouched. This is a licensed mutation and needs an active document - it throws “No active document.” otherwise. A linkMeshId that is neither a mesh nor a SubD raises ArgumentException “Object {id} is not a mesh.”. When no layout is feasible, the call raises InvalidOperationException carrying the layout search’s own problem description; a geometry failure raises “Sprue spiral computation failed with the given parameters.” (with the underlying detail appended in brackets when there is one) and nothing is added. Wrap the call in a Transaction so the whole spiral undoes in one step.