◆ Concrete
Concrete business card holder mold
A modern concrete business card holder, 110 mm wide with a chamfered front, cast from a silicone mold kit.
◆ Concrete
A modern concrete business card holder, 110 mm wide with a chamfered front, cast from a silicone mold kit.
A concrete business card holder 110 x 46 mm and 34 mm tall: a clean block with softly rounded edges, a chamfer along the front top edge, and one slot 95 mm long, 12 mm wide at the floor and 22 mm deep, its back wall leaning back 15 degrees so the cards stand at an easy angle. A US 89 mm or an EU 85 mm card fits lying landscape. In concrete it weighs about 314 g and stays put on a reception desk.
Made with the box mode of our silicone mold maker in its rectangular shape, the mode the tool itself suggests. Print the base with the holder fused onto it, the two walls and the two clamps, and pour about 416 ml of silicone. It fills the slot as a plug, and because the slot is widest at its mouth and the block widest at its foot, each cast slides out of the silicone with no cut.
Cast it grey for an office, white Jesmonite for a salon, or terrazzo with coloured chips for a shop counter. It pairs with the concrete desk organizer in this library. The zip carries every printed part, the holder master as its own STL, the tool's own print-settings sheet and a recipe file for the generator.
Shown as a 3D render of the printed mold parts pulled apart around the master, not a photo.
Print the base with the master fused onto it, the two walls and the two clamps.
Stand the base on the table. Set each wall down a few centimetres out from it and slide it in over the table until the ridge round the base sits in the groove at its foot, then slide the clamps down over the seams. Once they are on, the walls cannot lift, and the ridge seals the bottom.
Mix 451 ml of silicone in one batch and pour it into a corner, letting it rise around the master until it covers the top.
Once it has cured, take the clamps off, slide the walls straight out and pull the silicone block off the master. That block is your mold.
Turn the block over and stand it back inside the walls with the clamps on. The opening is the foot of the holder, with the slot plug standing in it.
Mix a fine concrete or Jesmonite to a thick pour, fill slowly round the plug, tap the walls for a minute to raise the air and strike the foot flat.
Leave it to cure for a day, take the walls off, peel the silicone off the sides and lift the holder straight up off the slot plug. Sand the foot flat, add felt pads and seal it.
Print details
| Cast material | Concrete |
|---|---|
| Printed parts | 5 |
| Size (W x D x H) | 138 x 74 x 72 mm |
| Print bed needed | 160 x 74 mm, 72 mm tall |
| Filament | ~247 g |
| Layer height | 0.2 mm |
| Infill | 15% |
| Supports | Not needed |
| Download | ZIP: 5 printed parts (STL) + card holder master (STL) + print sheet + recipe |
| Added | 2026-09-27 |
Pro early access until October 27, 2026, then free with any account.
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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 silicone mold maker guide.
About 35 standard cards, stacked in the slot and leaning back against its back wall. The slot is 12 mm wide at the floor and opens to about 19 mm at the top, so a fuller stack fans back a little and the front card stays readable.
Yes. Mix white cement or Jesmonite, fold in small chips of coloured Jesmonite or crushed tile, and pour. Once it has cured, sand the faces with wet 120 then 400 grit paper to open up the chips, and seal it. The slot faces stay smooth from the silicone.
Because the holder is a small block that is widest at its foot: the box is simple to set up, the silicone block slides off with no cut, and it takes only about 416 ml. The hugging shell saves silicone on big or tall pieces, not on a block this size.
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