Growing Tomato Plant - a free 3D model from Shapekit

A little raised bed, 14 cm square, with a crank on the side. At the start only the soil and a bamboo cane are in sight. Each turn of the crank the plant comes 28 mm further up: first the young top, then two leaves, then a leaf and a truss of yellow flowers, then two trusses of red tomatoes, and at the fifth turn the last two leaves. Then the crank stops. Turn it back and the plant sinks into the soil again, leaves folding up as they go. Under the bed you can watch how it works: a pair of bevel gears turns a Geneva drive, which moves one step per crank turn and locks in between, and the Geneva wheel turns a tube with two spiral slots that screws the stem up, like a lipstick. The leaves hang on filament pins and fall open under their own weight as soon as they clear the soil. Made as a Sinterklaas surprise, but it works just as well as a gift for anyone who grows tomatoes.

Parts (each STL is already placed the right way up for printing)
- growing-tomato-plant-base.stl: The floor with the four corner legs and the side wall that carries the crank. The other three sides are open, so you can see the gears work. On the floor: a ring that the tube turns on, a cross that centres the sleeve, a round rest for the driver and two holes for the bracket. Pegs on top of the legs locate the planter. Print: Floor down. No supports: the crank bearing has 45° undersides and a pointed bore. Needs a 144 × 139 mm bed.
- growing-tomato-plant-trough.stl: The raised bed itself: four plank walls on a bottom with a hole for the tube. Four corbels in the corners carry the soil. Print: Bottom down. No supports.
- growing-tomato-plant-soil.stl: A 10 mm plate covered in clods, with a crater in the middle where the plant comes up and a hole for the cane. The crater folds the leaves up again when the plant goes down. Print: Flat side down. No supports.
- growing-tomato-plant-stake.stl: A cane with knots, standing in the soil next to the plant. Print: Lying on its flat side. No supports.
- growing-tomato-plant-sleeve.stl: The fixed column in the middle. Its bore is shaped like a cross, with deeper pockets on two sides: the folded leaves and trusses ride up in these. Two straight slots at the bottom guide the rollers, so the stem can only move up and down, and a chamfer at the top folds the leaves in. Print: Standing up. No supports.
- growing-tomato-plant-tube.stl: A tube around the sleeve with two spiral slots; its foot is the Geneva wheel, with five slots. Each 30° that it turns pushes the rollers, and with them the stem, 28 mm up. Print: Geneva wheel down. No supports.
- growing-tomato-plant-bracket.stl: Holds the driver shaft in two bearings next to the tube. It stands against the crank wall with two pegs in the floor. Print: On its side, as in the file. No supports.
- growing-tomato-plant-driver.stl: The driver of the Geneva drive: a pin that moves the wheel one slot per turn and a locking disc that holds it still in between. After five steps the pin runs into the solid part of the wheel, and the crank stops. Print: Locking disc down. No supports.
- growing-tomato-plant-driver-shaft.stl: Vertical shaft from the driver up to the lower bevel gear, with a hex at each end and a collar under the gear. Print: Standing up, with a brim. No supports.
- growing-tomato-plant-bevel-gear.stl (print 2): 16 teeth, two the same: one on the driver shaft, one on the crank shaft, so a crank turn is a driver turn. Print: Back face down, teeth up. No supports.
- growing-tomato-plant-crank-shaft.stl: Through the bearing in the side wall: a hex inside for the bevel gear, a hex outside for the crank. Print: Lying as in the file, with a brim. No supports.
- growing-tomato-plant-crank.stl: Sits on the hex of the crank shaft. A nut for the grip screw goes in the pocket on its back. Print: Flat face down. No supports.
- growing-tomato-plant-grip.stl: Turns freely on an M3 × 30 screw. Print: Standing up. No supports.
- growing-tomato-plant-stem.stl: The plant's stem with its young top, ten forks for the leaves and trusses, and a square foot that slides in the sleeve. The two rollers are screwed into the foot. Print: Standing on its foot. No supports.
- growing-tomato-plant-roller.stl (print 2): Turns on an M3 × 20 screw in the stem foot and runs in a sleeve slot and a tube slot at once. Print: Standing up. No supports.
- growing-tomato-plant-leaf.stl (print 5): A serrated tomato leaf with a knuckle at its foot. Folded, it lies flat against the stem; out of the soil it falls open to 75° until its heel stops against the stem. Print: Outer face down. No supports.
- growing-tomato-plant-crown-leaf.stl (print 2): Two small leaves at the top of the plant, the first thing to come out of the soil. They open to 55°. Print: Outer face down. No supports.
- growing-tomato-plant-flower-truss.stl: A small Y-shaped plate with a knuckle, with holes for three flowers. Print: Plate down, knuckle up. No supports.
- growing-tomato-plant-flower.stl (print 3): Five petals with a peg on the back that glues into the truss. Print: Face down, peg up. No supports.
- growing-tomato-plant-tomato-truss.stl (print 2): The same Y plate as the flower truss, for three tomatoes. There are two of them. Print: Plate down, knuckle up. No supports.
- growing-tomato-plant-tomato.stl (print 6): A slightly flattened, ribbed tomato with a green calyx and a peg that glues into the truss. Print: Flat bottom down, calyx up. No supports.

Also needed (not printed)
- 1.75 mm filament for the 10 hinge pins: cut pieces of 8 mm and trim them flush.
- 2 × M3 × 20 screws for the rollers, 2 × M3 × 10 with washers for the ends of the crank shaft, and an M3 × 30 with a nut for the grip.
- A drop of glue for the flowers and tomatoes, and a little grease for the slots and the gears.
- Green and red filament make the plant: the other colours are up to you.

Print settings: 0.4 mm nozzle, 0.20 mm layer height (0.12 mm for the leaves, flowers and tomatoes), 3 walls, 15% gyroid infill, PLA material.

Assembly
1. Print the parts: Nothing needs supports. Print the two shafts with a brim. Clean any elephant's foot off the sleeve, the tube, the rollers and the gears, and check that the stem foot slides through the sleeve without catching.
2. Trusses: Glue the three flowers into the flower truss and three tomatoes into each tomato truss, pegs into the holes, the tomatoes' calyxes towards the plate.
3. Gear train: Put the bracket on the floor against the side wall, pegs in the holes. Push the driver shaft down through both bearings into the hex of the driver, which stands on its round rest, and put a bevel gear on top. Push the crank shaft through the side wall from the inside, put the second bevel gear on its inner hex and fix it with an M3 × 10 and a washer. Fit the crank on the outer hex the same way, and the grip with the M3 × 30 and its nut.
4. Column: Slide the tube over the sleeve and stand both in the middle of the floor: the lugs of the sleeve go into the gaps in the ring, and the Geneva wheel must mesh with the driver. Turn the crank until it stops at the bottom end.
5. Stem and rollers: Lower the stem into the sleeve until the screw holes in its foot line up with the bottom of the slots. Screw an M3 × 20 through each roller, the tube slot and the sleeve slot into the foot. Turn the crank: five turns and the stem should be all the way up. Leave it there.
6. Leaves: With the stem up, hang every leaf and truss in its fork and push a filament pin through. The pin is tight in the fork and loose in the knuckle, so the leaf swings freely. From the top: the two young leaves, then two leaves, then a leaf and the flower truss, then the two tomato trusses, and the last two leaves at the bottom.
7. Bed: Put the planter on the legs, pegs into the sockets and the column through the hole in its bottom. Lay the soil on the corbels, with the sleeve in the crater, and push the cane into its hole.
8. Try it: Turn the crank back five times: the leaves fold up as they meet the crater and the plant disappears. Now it is ready to give. Each turn forward grows one stage; after five turns the crank stops.

Safety: Small parts, filament pins and screws: keep them away from small children.

License: Creative Commons Attribution-NonCommercial 4.0 (CC BY-NC 4.0)
https://creativecommons.org/licenses/by-nc/4.0/
Print it, remix it and share it, as long as you credit Shapekit and don't sell the files or the prints.
