--- title: "3D print a jack-o'-lantern that fits your LED tea lights" description: "Design a pumpkin lantern or tea light cover around your own LED candles: the sizes to measure, wall thickness for glow, the face cut-outs, and the prompt." canonical: https://speakcad.com/blog/halloween-tea-light-lantern-3d-print published: 2026-10-18 updated: 2026-10-18 publisher: SpeakCAD --- # 3D print a jack-o'-lantern that fits your LED tea lights > Design a pumpkin lantern or tea light cover around your own LED candles: the sizes to measure, wall thickness for glow, the face cut-outs, and the prompt. A printed jack-o'-lantern is the most satisfying Halloween print there is: switch the LED on, turn off the light, and the face appears. It is also the one that most often goes wrong, because the tea light does not fit, or the glow is a dull smudge through a wall that is too thick. Both are numbers. Here they are. ## Measure the tea light first | What to measure | Typical LED tea light | Why it matters | |---|---|---| | Diameter | 36 to 38 mm | The opening at the bottom: add 1 mm | | Height with the flame | 35 to 45 mm | The lantern must be taller, or the flame shows at the top | | Switch position | Underneath, usually | Leave the bottom open so you can reach it | | Larger "pillar" LED candles | 50 to 75 mm across | Same rule, bigger pumpkin | Measure yours with a ruler or a calliper: brands differ, and a 1 mm miss is the difference between a lantern that drops over the candle and one that sits on it. ## Wall thickness: the glow Light through printed plastic depends on the wall and the colour: - **White or natural PLA, 1.2 to 2 mm walls:** the whole pumpkin glows softly, the face glows bright. The best look. - **Orange PLA, 1.6 to 2 mm:** a warm glow, the face stays the brightest part. - **Black or dark PLA, any wall:** only the cut-outs light up. Classic and spooky. - **Over 3 mm:** the body stays dark in any colour. Ask for the wall as a number ("2 mm walls"): the AI keeps it, and you can change it later with a quick edit (1 credit). ## The face: cut through, and printable The eyes, nose and mouth are holes through the front wall. Two rules make them print cleanly: 1. **Triangles point up.** A triangle eye with its point at the top prints without supports; upside down, its flat top bridges. 2. **Gaps of at least 2 mm** between teeth, or they fuse into one blob. ## Three ways to make it **By hand, free.** A square lantern: start from the open box shape and type 60 x 60 x 70 mm with 1.6 mm walls: a floor and four walls, already open on one side. Tap the front wall and use Cut with the polygon to draw two triangle eyes and a jagged mouth, corner by corner, through. Add a name in raised Text on a side wall. Print it open side up, as it comes, and turn it over the tea light: the floor becomes the lid. Nothing to pay, the download included. **With the AI, a real pumpkin shape.** Round, ribbed, with a stem: describe it with the tea light's numbers (the first prompt below). The AI writes it as a parametric model, so the size, the ribs and the wall stay numbers you change in the viewer. **Remix one you downloaded.** Found a pumpkin on Printables whose opening is 2 mm too small? Upload the STL and ask for the opening: "make the opening at the bottom 39 mm across". [How to change a downloaded STL](/edit-stl). ## Print settings - **No supports** for a pumpkin open at the bottom: the dome closes in gently. If the AI's dome is too flat, ask for "a dome no flatter than 45 degrees". - **0.2 mm layers, 2 or 3 walls, 15 % infill.** The infill hardly matters on a shell. - **Vase mode** works for a plain round lantern without a face, then cut the face with a hobby knife. With a face, print it normally. ## What it costs Shaping a part by hand (a hole, a cut, an added shape, text, rounded corners, a shell, every size typed in millimetres) is free, and so is downloading what you shaped. With the AI, a new part or a design change spends 3 credits, a small change 2 credits and a quick edit (a changed size or number) 1 credit; downloads are included in every plan, 4 credits without one. A new free account also gets its first AI part free (not offered in every country): some accounts get the credits right away, others confirm with a card first (a free trial, nothing charged that day); downloading the part spends 4 credits without a plan, like any AI work (every plan includes downloads). ## The Halloween code: SPOOKY40 40% off your first month of any plan with the code SPOOKY40, until 2 November (first subscription). It applies itself at checkout when you came through one of these Halloween pages, and you can type it on the payment page too. Start with Maker: 50 credits a month for $7.99, cancel anytime. The hand tools, and the download of what you shape with them, are free without it. Every Halloween part and its prompt on one page: [Halloween 3D prints](/halloween-3d-prints). ## Prompts to try - A jack-o'-lantern cover for an LED tea light 38 mm across and 40 mm tall: a hollow pumpkin 75 mm across and 70 mm tall with eight vertical ribs, 2 mm walls, open at the bottom with a 39 mm opening, two upward-pointing triangle eyes, a triangle nose and a toothy grin with 2 mm gaps cut through the front, a short curved stem on top, printable without supports ([open in SpeakCAD](https://app.speakcad.com/signup?next=%2F%3Fprompt%3DA%2520jack-o'-lantern%2520cover%2520for%2520an%2520LED%2520tea%2520light%252038%2520mm%2520across%2520and%252040%2520mm%2520tall%253A%2520a%2520hollow%2520pumpkin%252075%2520mm%2520across%2520and%252070%2520mm%2520tall%2520with%2520eight%2520vertical%2520ribs%252C%25202%2520mm%2520walls%252C%2520open%2520at%2520the%2520bottom%2520with%2520a%252039%2520mm%2520opening%252C%2520two%2520upward-pointing%2520triangle%2520eyes%252C%2520a%2520triangle%2520nose%2520and%2520a%2520toothy%2520grin%2520with%25202%2520mm%2520gaps%2520cut%2520through%2520the%2520front%252C%2520a%2520short%2520curved%2520stem%2520on%2520top%252C%2520printable%2520without%2520supports)) - A ghost luminary for an LED tea light 38 mm across: a tall rounded ghost 70 mm wide and 110 mm tall with a wavy bottom edge, 1.6 mm walls, open at the bottom, two oval eyes 12 x 18 mm and an open mouth cut through the front ([open in SpeakCAD](https://app.speakcad.com/signup?next=%2F%3Fprompt%3DA%2520ghost%2520luminary%2520for%2520an%2520LED%2520tea%2520light%252038%2520mm%2520across%253A%2520a%2520tall%2520rounded%2520ghost%252070%2520mm%2520wide%2520and%2520110%2520mm%2520tall%2520with%2520a%2520wavy%2520bottom%2520edge%252C%25201.6%2520mm%2520walls%252C%2520open%2520at%2520the%2520bottom%252C%2520two%2520oval%2520eyes%252012%2520x%252018%2520mm%2520and%2520an%2520open%2520mouth%2520cut%2520through%2520the%2520front)) - A square lantern 60 x 60 x 70 mm, 1.6 mm walls, open at the bottom, a different Halloween face cut through each of the four sides (triangle eyes pointing up), and BOO in raised letters 10 mm high on top ([open in SpeakCAD](https://app.speakcad.com/signup?next=%2F%3Fprompt%3DA%2520square%2520lantern%252060%2520x%252060%2520x%252070%2520mm%252C%25201.6%2520mm%2520walls%252C%2520open%2520at%2520the%2520bottom%252C%2520a%2520different%2520Halloween%2520face%2520cut%2520through%2520each%2520of%2520the%2520four%2520sides%2520(triangle%2520eyes%2520pointing%2520up)%252C%2520and%2520BOO%2520in%2520raised%2520letters%252010%2520mm%2520high%2520on%2520top)) - A pumpkin lantern for a pillar LED candle 75 mm across and 100 mm tall: 130 mm across, 2 mm walls, ribbed, open at the bottom with a 77 mm opening, and a jagged grin ([open in SpeakCAD](https://app.speakcad.com/signup?next=%2F%3Fprompt%3DA%2520pumpkin%2520lantern%2520for%2520a%2520pillar%2520LED%2520candle%252075%2520mm%2520across%2520and%2520100%2520mm%2520tall%253A%2520130%2520mm%2520across%252C%25202%2520mm%2520walls%252C%2520ribbed%252C%2520open%2520at%2520the%2520bottom%2520with%2520a%252077%2520mm%2520opening%252C%2520and%2520a%2520jagged%2520grin)) ## FAQ ### How do I make a 3D printed jack-o'-lantern? Measure your LED tea light (usually 36 to 38 mm across), then describe a hollow pumpkin with an opening 1 mm wider, 1.6 to 2 mm walls and the face cut through, in SpeakCAD. It renders in your browser, and you download the STL, the 3MF or G-code for your printer. A square lantern can also be shaped by hand from the open box shape, free. ### Can I put a real candle in a 3D printed lantern? No. PLA softens around 60 °C and PETG around 80 °C, and both burn. Use LED tea lights or LED pillar candles only. ### What colour filament glows best? White or natural PLA with 1.2 to 2 mm walls: the whole lantern glows and the face is brightest. Black filament lights up only the cut-outs. ### Does a pumpkin lantern need supports? Not when it is open at the bottom and its top closes in no flatter than 45 degrees. Point triangle eyes upwards so their tops do not need a bridge. ## About SpeakCAD SpeakCAD is the most intuitive CAD for 3D printing, made for people who own a 3D printer and need a part that fits something they have: tap a face and type a size to shape it with simple tools, or describe it to the AI, on your phone or computer, and download a print-ready STL, 3MF or G-code sliced for your printer. SpeakCAD works inside ChatGPT and Claude as a plugin (an MCP server): ask the assistant for a part with its measurements and SpeakCAD's own CAD AI designs it, shows it in 3D in the chat and hands over a print-ready STL, 3MF or G-code sliced for your printer. - Live demo, no account: https://speakcad.com/demo - In ChatGPT, Claude and other MCP clients: https://speakcad.com/chatgpt-plugin, https://speakcad.com/claude-connector, https://speakcad.com/mcp-server - Pricing: https://speakcad.com/pricing - FAQ: https://speakcad.com/faq - Site index for AI assistants: https://speakcad.com/llms.txt