What this test can establish

The shoe stops when its actual outline would enter the walls of the crossing. The red ghost shows the pose you requested. The round control can rotate at the centre; the pointed shoe encounters a wall. This is a quasistatic geometric constraint test, with no motor or simulated contact forces.

This 60° crossing is a separate development coupon. It is not a replacement cartridge for the main machine. The braider’s curved track, horn drive, adjacent carriers and transfer timing still require a coupled design and handoff test.

Make the hand test

1. Cut the 6 mm base, 6 mm track and 3 mm cover. Retain all four track islands and cover pieces. Dimensions are nominal; measure kerf and stock first.
2. Print the pointed shoe, round control and handle. Use a flat underside on the bed. Clean the slot surfaces and counterbore. The M3 screw head must sit below the sliding face.
3. Place a shoe between the base and track; add the cover. Use the four corner M3 bolts to hold each island to the base. Fit the handle with the recessed M3 × 12 screw and captured nut. Leave the handle clear of the cover.
4. Move the shoe by hand through the crossing in both directions. At the centre, gently try turning toward the other branch. Repeat with the round control and record the difference.
5. Record measured slot width, shoe width, free travel, rotation before contact, snagging and any lift. Adjust fit before repeating. Do not power this coupon.

Mechanism precedents and limits

Real maypole carriers use shaped guides and supporting horn components. US4774871A describes paired boat-shaped sliders; US20190380707A1 describes pivoting keels and carrier-retaining plates. These are architecture references. This original straight-crossing coupon does not reproduce or validate either complete machine.

The displayed motion advances in small translation/rotation increments and stops at the first detected intersection, then refines that contact. It is not a continuous-time rigid-body simulation or a proof that no other route exists in the full space of translations and rotations. The exported CAD separately checks a clear straight traverse.