How to make a custom coaster
- Choose the shape and size. Round, rounded square or hexagon, 80–120 mm. 100 mm fits most mugs and glasses.
- Pick a pattern – honeycomb, waves, geometric, mandala or dots – and set its scale and line width.
- Add a monogram if you like: one to three letters, with or without a ring, on its own or over the pattern.
- Set the colours to preview the two-colour look, and tick "Pad recesses" if you use felt pads.
- Download a single STL (with a colour change), the 2-colour ZIP for AMS / MMU printers, and the holder.
Printing it in two colours
Every coaster is a flat base with the rim and pattern raised on top, so the second colour starts at one height. The stats under the preview show where.
| Printer | What to do |
|---|---|
| Single-colour | Download the STL and add a filament change (pause / M600) at the height shown, 3.0 mm by default. Swap to the second colour when the printer stops. |
| AMS, MMU or tool-changer | Download the 2-colour ZIP, load both STLs as one object with two parts, and assign a filament to each. |
| One colour only | Print the STL as it is. The raised pattern still reads well, especially with ironing on the top. |
Recommended print settings
| Setting | Value |
|---|---|
| Material | PLA for cold drinks; PETG or ASA for hot mugs |
| Nozzle | 0.4 mm |
| Layer height | 0.2 mm (keep the base thickness a multiple of it) |
| Walls | 2–3 |
| Top / bottom layers | 4 / 4 |
| Infill | 15–20%, gyroid or grid |
| Ironing | Optional, on the top surface for a smooth, even finish |
| Supports | None |
Tips for great coasters
- Contrast sells the pattern. White on teal, gold on black and white on navy all look sharp. Light filaments are slightly translucent, so over a dark base a pattern height of 1.2 mm keeps white bright.
- Print on a textured PEI sheet for a matt, grippy underside that hides fingerprints.
- Print a set in one go. Arrange four or six copies on the plate; with a single filament change they all switch colour together.
- Keep lines at 1.6 mm or more for PETG, which strings more than PLA over short gaps.
- Print the holder in one of the two coaster colours so the set looks matched on the table.
Want the same two-colour look on a gift tag? Try the Name Keychain Generator.
Frequently asked questions
How do I print a two-colour coaster on a single-colour printer?
Add a filament change (M600 or a pause) in your slicer at the height shown under the preview – the base thickness, 3.0 mm by default. The base prints in the first colour; after the swap, the rim and the pattern come out in the second colour. Set a base thickness that is a whole number of layers (3.0 mm at 0.2 mm layers) so the change lands exactly between two layers.
What is in the 2-colour ZIP?
Two STL files that line up exactly: the base (colour 1) and the rim with the pattern (colour 2). Load both into Bambu Studio, OrcaSlicer or PrusaSlicer at the same time, answer "yes" when asked to treat them as one object with several parts, and assign a filament to each part. This is the way to go with an AMS, MMU or tool-changer.
What size should a coaster be?
100 mm suits mugs, tumblers and most glasses, and is the classic size for a coaster set. Go to 90 mm for a small cup or espresso glass, and 110–120 mm for large mugs, pint glasses or a teapot. The raised pattern is only 1 mm high and the top is flat, so glasses stand steadily on any pattern.
Can I put a hot mug on a 3D printed coaster?
PLA starts to soften at about 55–60 °C, and a mug of fresh tea or coffee can be hotter than that underneath. For hot drinks print in PETG, ASA or ABS, or make the base thicker (4 mm or more). PLA is fine for cold drinks, glasses and houseplants.
Why can the lines not be thinner than 1.2 mm?
A 0.4 mm nozzle lays down lines about 0.45 mm wide, so 1.2 mm gives each pattern line at least two clean passes. Thinner lines print as gaps or blobs, and they are fragile when the top colour is printed on its own. The line width slider stops at 1.2 mm for that reason.
How do I stop coasters from sliding or scratching the table?
Tick "Pad recesses" and the generator adds four shallow pockets (10 mm across, 0.6 mm deep) underneath. Stick in self-adhesive felt or rubber bumper pads of 10 mm diameter and they sit flush, so the coaster does not rock. The base needs to be at least 2 mm thick for the pockets.
How does the coaster holder work?
Click "Holder STL" to download a tray in the same shape as your coasters, with 1 mm clearance all round so they drop in easily. Its walls are about 60 % as tall as the stack, so the coasters stand proud and are easy to grab, and a finger notch in the front wall lets you take the top one off. Choose how many coasters it holds (4–8) under "Holder".