Convert text to STL
The STL export extrudes each letter into a solid: the filled area of the glyph is triangulated into a top and a bottom face, joined by vertical side walls. The result is watertight, which is what a slicer needs in order to produce clean toolpaths.
Convert text to STLA mesh a slicer will accept
Every glyph’s outline is resolved against its counters before triangulation, so the bar of an “A” is solid and its triangle is a hole all the way through. Top and bottom faces are triangulated independently and stitched with vertical walls along every boundary edge, leaving no unmatched edges for the slicer to complain about.
- Extrusion depth is yours to set; left alone it defaults to a fifth of the text height, which reads well for signage.
- STL carries no unit header — slicers read the raw numbers as millimetres — so the unit you pick scales the solid instead of being declared. The default keeps the “1 unit = 1 mm” printing convention.
- Each glyph is self-unioned regardless of the weld setting, so overlapping font contours never produce internal walls.
Solid letters or hollow ones
Fill alone extrudes the letterform as a solid block. Outline alone extrudes just the band around its edge, giving hollow letters with a wall of the stroke width — useful for inlays, light boxes, and anything you plan to pour resin into. Both together give the solid plus its surrounding band.
What to print it on
The mesh is a plain ASCII STL, so it loads in Cura, PrusaSlicer, Bambu Studio, Orca, Simplify3D and every CAD package. For keychains and signs, add depth before exporting rather than scaling the Z axis in the slicer — extruding here keeps the letter faces flat and the walls exactly vertical.
Questions
- Is the STL watertight / manifold?
- Yes. Faces are built from the same boundary edges the walls are stitched along, so the solid closes. Slicers and mesh repair tools should report no holes.
- How do I set the physical size?
- Font size is the letter height in geometry units and one unit is one millimetre by default, so a font size of 100 prints 100 mm tall. Change the unit selector to work in centimetres or inches instead.
- Can I get connected, single-piece lettering?
- Use a script face whose letters overlap, or reduce the letter spacing until they do. Overlaps are unioned per glyph, and touching glyphs print as one piece — the usual trick for a keychain or a sign that has to survive being handled.
- Is it binary or ASCII STL?
- ASCII. It is larger on disk but reads everywhere, and it stays diff-able if you keep exports in version control.