Cauldron Jack-O-Lantern

The "Jack-o-Cauldron" Lamp, Full Size 🎃🔮

My daughters love fall, and Halloween most of all, so I am building them a set of Halloween pieces for the 2026 season. The Bubbling Brew Cauldron Lamp was the first, the Jack-o-Lantern was the second, and the little Jack-o-Cauldron Tea Light crossed the two of them at 75 mm.

This is that crossing at FULL size. The big 166 mm cauldron, a face carved clean through the front, a lift-off lid, and a color-changing RGB puck light glowing under a disc of printed bubbles. The face glows. The brew glows. Both at once.

🟩 𝗪𝗛𝗔𝗧 𝗠𝗔𝗞𝗘𝗦 𝗜𝗧 𝗪𝗢𝗥𝗞

▸ 𝗜𝘁 𝗚𝗹𝗼𝘄𝘀 𝗧𝘄𝗼 𝗪𝗮𝘆𝘀 𝗔𝘁 𝗢𝗻𝗰𝗲 — Light comes out through the carved face and up through the Bubbling Brew disc resting in the mouth. A jack-o-lantern glows through its face. A cauldron lamp glows through its brew. This one does both, at a size you can see across a room.

▸ 𝗙𝗼𝘂𝗿 𝗣𝗮𝗿𝘁𝘀, 𝗡𝗼 𝗛𝗮𝗿𝗱𝘄𝗮𝗿𝗲 — Body, lift-off lid, diffuser cone and the Bubbling Brew insert. Nothing to glue, no screws, no magnets. Everything stacks.

▸ 𝗔 𝗥𝗲𝗮𝗹 𝗖𝗼𝗿𝗱 𝗥𝗼𝘂𝘁𝗲 — The puck light sits in a recess in the floor of the pot and its lead runs out through a hole beside it. No cord pinched under the rim, and no lifting the pot to get at the switch.

▸ 𝗧𝗵𝗲 𝗗𝗶𝗳𝗳𝘂𝘀𝗲𝗿 𝗜𝘀 𝗡𝗲𝘄 — A vase-mode cone, one wall thick, 123 mm across the wide end and 97 mm tall. It goes in upside down from the way it prints: the narrow 77 mm end drops over the puck and the wide face carries the light up to the brew. Without it the light stays a bright spot in the bottom of the pot.

▸ 𝗖𝗮𝘀𝘁-𝗜𝗿𝗼𝗻 𝗧𝗲𝘅𝘁𝘂𝗿𝗲 — Body and lid print with a stippled surface that reads as rough cast iron straight off the plate in black PLA. No painting, no post-processing.

▸ 𝗟𝗶𝗱 𝗢𝗻 𝗢𝗿 𝗢𝗳𝗳 — Leave the lid on for a closed cauldron on a shelf; lift it off and the brew bubbles over the rim.

🟩 𝗧𝗛𝗘 𝗟𝗜𝗚𝗛𝗧 (𝗦𝗢𝗟𝗗 𝗦𝗘𝗣𝗔𝗥𝗔𝗧𝗘𝗟𝗬)

Built around a standard round RGB LED puck light — 59.5 mm across and 8.3 mm tall, the kind sold in 3-packs with a 24-key remote for about $20. Aluminum housing, USB powered, with an inline switch on a 1.5 m lead. 16 colors and 4 gradient modes.

The LIGHT changes color, not the print. The diffuser and the brew disc are white, so whatever you set on the remote, the cauldron follows. One 3-pack lights three of these.

Any puck up to 59.5 mm across and 8.3 mm tall drops straight in — there is room to spare, so smaller is fine. Much taller and it will lift the diffuser.

🟩 𝗧𝗛𝗘 𝗡𝗨𝗠𝗕𝗘𝗥𝗦

▸ 𝗕𝗼𝗱𝘆: 𝟭𝟲𝟲 × 𝟭𝟱𝟴 × 𝟭𝟭𝟭 𝗺𝗺 — 14h 16m and 217.04 g

▸ 𝗟𝗶𝗱: 𝟭𝟯𝟰.𝟱 𝗺𝗺 𝗮𝗰𝗿𝗼𝘀𝘀 × 𝟯𝟯 𝗺𝗺 — 6h 25m and 68.26 g

▸ 𝗗𝗶𝗳𝗳𝘂𝘀𝗲𝗿: 𝟭𝟮𝟯 𝗺𝗺 𝗮𝗰𝗿𝗼𝘀𝘀 × 𝟵𝟳 𝗺𝗺 𝘁𝗮𝗹𝗹 — 1h 18m and 22.37 g

▸ 𝗕𝘂𝗯𝗯𝗹𝗲 𝗶𝗻𝘀𝗲𝗿𝘁: 𝟭𝟯𝟰.𝟱 𝗺𝗺 𝗮𝗰𝗿𝗼𝘀𝘀 × 𝟭𝟯 𝗺𝗺 — 2h 19m and 27.59 g

▸ All four parts: 24h 18m and 335.26 g, about $10 of PLA

🟩 𝗣𝗥𝗜𝗡𝗧 𝗦𝗘𝗧𝗧𝗜𝗡𝗚𝗦

Three 3MF projects, each already set up:

▸ 𝗕𝗼𝗱𝘆 𝗮𝗻𝗱 𝗹𝗶𝗱 — ONE project, TWO plates. Tree supports required · 0.25 mm support Z gap · 3 support interface layers · 5 mm brim · 0.12 mm layer height · 3 walls · 15% gyroid

▸ 𝗗𝗶𝗳𝗳𝘂𝘀𝗲𝗿 — VASE MODE · one wall · 0.2 mm layer height · no supports · its own plate

▸ 𝗕𝘂𝗯𝗯𝗹𝗲 𝗶𝗻𝘀𝗲𝗿𝘁 — No supports · 0.08 mm layer height · 2 walls · 8% lightning infill · concentric top surface

Only the body and the lid need supports. Turn them off for the diffuser and the insert — neither part wants them, whatever the switch says when the project opens.

The fine layer height and concentric top surface on the insert are what keep the bubble domes smooth. Coarser layers terrace them visibly, so it is worth the extra time. Print the diffuser and the insert in white or a light translucent PLA so they diffuse properly.

The body is an overnight print at 14h 16m and 217 g. The diffuser and the brew disc together are only 3h 37m, and they are the two parts you want in a light filament, so they make a natural pair to run on their own.

PLA · 220°C nozzle · 60°C bed · sliced on a Creality Hi 2 with a 0.4 mm nozzle

🟩 𝗧𝗛𝗘 𝗥𝗘𝗦𝗧 𝗢𝗙 𝗧𝗛𝗘 𝗙𝗔𝗠𝗜𝗟𝗬