One sign, two pictures
- Type two words or add two pictures.
- Look from the left and the right in the preview.
- Download — one part per filament colour.
A flip sign shows one picture from the left and another from the right — the ridged "agamograph" effect, printed in colour. Type two words (MOM / DAD, YES / NO, a name and a date) or add two pictures, pick the colours, check both views in the preview and download a 3MF with one part per filament for your AMS or MMU.
New — 6 November 2026: first version. Written by Ned Walsch, who also makes the shadow sculpture maker and the lithophane studio.
| Setting | Value | Why |
|---|---|---|
| Orientation | Flat, ridges up, as exported | 45° slopes print cleanly without supports. |
| Layer height | 0.12–0.16 mm | The colours change layer by layer on the slopes; finer layers give sharper edges. |
| Walls / infill | 3 walls, 15 % infill | The coloured skin is 0.8 mm; walls keep it solid. |
| Filament | Matte PLA in high-contrast colours | Shine on the slopes washes the picture out at an angle. |
| Purge | Prime tower on, flush into infill | Saves filament on the many colour changes. |
The sign is a plate covered in small triangular ridges. The slopes that face left carry picture A and the slopes that face right carry picture B, each squeezed into half the width so a viewer at about 45° sees the whole picture. Walk past it and the sign flips from one to the other.
For a clean result, yes — a Bambu Lab AMS, Prusa MMU, a toolchanger or anything that prints several filaments in one job. Each colour is its own part: open the 3MF, give each part a filament and print. On a single-colour printer you can pause for a filament change, but because the colours sit on the slopes they change layer by layer, so it only works roughly.
Two for words (the sign colour and the letter colour, both picked by you). For pictures, 2, 3 or 4: the photos are reduced to that many shared colours, lightest first; the lightest becomes the body of the sign.
5 mm (the default) suits signs 100–200 mm wide viewed from a metre or two. Smaller ridges (3–4 mm) give finer pictures but need fine layers (0.12 mm) to keep the colour edges clean; larger ridges (6–8 mm) suit big signs seen from further away.
Flat, ridges up, exactly as exported — no supports. 0.12–0.16 mm layers give the sharpest colour edges on the slopes; 3 walls and 15 % infill are plenty. The stand prints flat in any colour and holds the sign upright by a plain strip along its bottom edge.
Short ones with bold letters: names (MOM / DAD), YES / NO, a team name and a year. Both words are fitted to the sign width, so very different lengths make one word smaller. Pacifico gives a script look; Archivo Black and Bebas Neue are the most legible.