raygeo.cnc.plan.thread_milling

CNC thread-milling plan builder.

Produces a plan that thread-mills internal threads: one helical interpolation cycle per pilot bore, all sharing the same thread parameters. Bores come either from an explicit center list or are detected automatically as circular island contours of the face and validated against the thread geometry.

Functions

plan_thread_milling()

plan_thread_milling(
    part: ops.part.Part,
    face_id: str = '',
    nominal_diameter: float = 6,
    pitch: float = 1,
    tool_diameter: float = 4,
    z_top: float = 0,
    z_bottom: float = -12,
    handedness: str = 'rh',
    safe_z: float = 5,
    feed_rate: Optional[float] = None,
    plunge_feed: Optional[float] = None,
    spindle_rpm: Optional[int] = None,
    coolant: Optional[str] = None,
    holes: Optional[Sequence[tuple[float, float]]] = None,
    hole_tolerance: float = 0.1,
    hole_order: str = 'detection',
) -> cnc.plan.Plan

Build a plan that thread-mills internal threads on one face.

One helical-interpolation cycle per pilot bore; all bores share the thread parameters. Bores come from holes when given (explicit centers), otherwise they are detected as circular island contours of the face and validated: the thread mill must fit into the bore, and the bore must not be oversized beyond the thread minor diameter (or there is nothing left to thread). The thread length (z_top - z_bottom) must be an integer multiple of the pitch. Bores needing different parameters need a separate call.

Parameter	Type	Description
part	ops.part.Part	part whose face is threaded.
face_id	str = ''	face to thread ("" is the default face).
nominal_diameter	float = 6	nominal (major) thread diameter (mm).
pitch	float = 1	thread pitch (lead) (mm).
tool_diameter	float = 4	thread mill cutter diameter (mm); must be below the minor diameter.
z_top	float = 0	Z of the top end of the thread (default 0).
z_bottom	float = -12	Z of the bottom end of the thread.
handedness	str = 'rh'	"rh" (default) or "lh".
safe_z	float = 5	safe rapid height (default 5).
feed_rate	Optional[float] = None	cut feed (mm/min); None leaves the plan's cut state unset.
plunge_feed	Optional[float] = None	vertical plunge feed (mm/min); None falls back to the cut feed.
spindle_rpm	Optional[int] = None	spindle speed (rpm).
coolant	Optional[str] = None	"flood", "mist" or "off"; None leaves the plan's coolant unset.
holes	Optional[Sequence[tuple[float, float]]] = None	explicit pilot-bore centers [(x, y), ...]; None detects circular islands on the face.
hole_tolerance	float = 0.1	max distance (mm) between an island contour sample and the fitted circle for it to count as a bore (default 0.1).
hole_order	str = 'detection'	"detection" or "nearest_neighbor".
Returns	cnc.plan.Plan	the thread-milling plan, one step per bore.

Thread milling M6x1 threads on two detected pilot bores; the helix climbs one pitch per revolution.