◆ Soap
Six scallop shell guest soaps from one silicone tray, ribs and hinge included.
A tray of six scallop shells, 64 mm wide, 55 mm tall and 20 mm deep: the classic guest-soap size, with thirteen ribs fanning out from the hinge and a scalloped rim.
Made with our tray mold generator in its flexible silicone tray mode: print the caster, pour silicone into it and peel out a flexible six-shell tray. Soap and wax both release from silicone far better than from a printed tray, and the ribs come out crisp.
The zip carries the printed caster exactly as the tool exported it, one shell on its own as an STL, the master uploaded to the tool, and a print and pour sheet with the silicone figure the tool measured.
Shown as a 3D render of the printed caster with three shell soaps in front, not a photo.

Print the caster as exported, open side up. It is one part, so there are no seams to seal. No supports.
Set it on a level surface. Mix 396 ml of silicone in one batch and pour it into one corner in a thin stream, letting it flow round the raised shapes until it is level with the rim.
Tap the caster on the table for a minute to bring the bubbles up, then let the silicone cure for as long as its datasheet says.
Peel the cured silicone out of the caster. That silicone is your tray, and the caster is ready for another one.
Fill each cavity, let it set, then flex the tray and peel it back to pop the pieces out.
Print details
| Cast material | Soap |
|---|---|
| Printed parts | 1 |
| Size (W x D x H) | 215 x 127 x 31 mm |
| Print bed needed | 215 x 127 mm, 31 mm tall |
| Filament | ~210 g |
| Layer height | 0.2 mm |
| Infill | 15% |
| Supports | Not needed |
| Download | ZIP: printed caster (STL) + one soap (STL) + tool master (STL) + print and pour sheet |
| Added | 2026-09-24 |
Made with the free Tray mold generator. Upload your own model and get the same kind of mold built around it, in your browser.
Free download. Opens the Thingiverse listing in a new tab.
Free for personal use. Selling the pieces you cast needs a commercial licence (Pro or Founder); passing on the file itself is not permitted on any plan. Full terms.
New to casting? Read the ice cube tray mold guide.
About 45 ml per shell, so a full tray of six takes roughly six times that. Melt a little extra: melt-and-pour soap loses some to the jug, and a shell poured short shows as a thin back.
Stir a pinch of pearl or white mica into a clear melt-and-pour base before pouring. The ribs catch the shimmer. Wipe the tray dry first, because water beads leave dull spots on the face of the soap.
Yes. At about 45 ml each the shells are large for wax melts but make good floating candles: push a short tabbed wick into the wax at the hinge end while it is still soft.
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