A rubber-band car for a physics brief: five meters minimum, the longest run wins. Earnie picked the reference, the Cirin, and directed the design through Claude. v1 was a flat lattice. Four reviews found its winding hook hit the deck on all 57 positions checked, so the axle could never turn a full circle.
v2 fixed every v1 finding, then lost the side-by-side with the car it was copying. It looked like a carrot on wheels of swiss cheese. It was drawn from the drivetrain outward, and the shape came last.
v3 started from the silhouette: an F1 stance, a torpedo in profile, a waist and a swell in plan. The mechanics had to fit inside the outline.
The band hides in the spine and pulls through a 2:1 pulley, so the axle feels half the pull over twice the string. Grip sets the limit, and this keeps the launch under it.
Two days of printing on whichever machine was free. The dissolvable-support printer had an empty bath, so the chassis moved to PLA. Most print decisions were made by what broke.
Every part, registered. The build book walks twelve steps in this order.
Built by Thursday evening. Spun by hand with the wheels in the air, everything turned.
Then it went on the ground. Wound by hand and set down on the street, it went somewhere between zero and three feet.
Twenty-four turns of the axle should have rolled it 5.7 meters. At most 16% reached the road. The set screws never held the hubs or the drive peg on a polished 3 mm rod, so the axle spun inside its own wheels. The whole build, the physics and the failure are at togoat.aaand.space.
| 01 | dory | 7 plates · june 2026 |
| 02 | grow-lab | 3 plates · 2026-09-04 |
| 03 | workbench | 9 plates · 2026-09-23 |
| 04 | cnc-station | 3 plates · 2026-09-19 |
| 05 | togoat | 9 plates · 2026-10-02 |
this scroll accumulates · entries are added while the work is kept · aaand.space 2026