18in Concrete Cake Stand Mold

thingiverse

This is a sturdy cake stand mold, measuring 18 inches in diameter, commissioned by Blue Llama Events, a Mid Western Event Planner specializing in weddings. It's designed to hold a substantial wedding cake, and this reusable mold makes a 40-pound cake stand when filled with glass fiber reinforced concrete. Steps: Print out eight of each: Mold, Upper Clamp, and Lower Clamp, one Center, and one Center Support. Use PLA for everything except the clamps, where PETG is recommended. Get some glass-reinforced concrete and sift out the largest stones. I attached the sifter I used; it wasn't a ton of fun, so wear a mask and eye protection. Check out the photo; I had a fan pulling the dust away from me. Cut a piece of board large enough to form the floor (I poured top down), and coat the whetted surface in three coats of Thompson water sealer or a similar product. Sand all the whetted plastic surfaces very smooth, then wax the mating mold to mold surfaces. Alternatively, you can skip this step if you don't plan to reuse the molds. When assembling the molds, apply a thin bead of caulk around the mating mold faces about 0.25 inches back from the forming or whetted faces (use non-adhesive caulk). Use the appropriate dovetailed clamps (top and bottom are different and should fit flush; print these out of PETG if you can). For added security, wrap a rope or strap around the whole thing to make a tight circle. Also apply a caulk bead where it's mating to the board. After mold assembly, use cooking spray or PAM as the secret concrete mold release. Emphasize securing the clamps tightly (check out the red cups over clamps in the photo to prevent eye damage when not paying attention). Mix and pour the concrete in layers as quickly as possible, ensuring a good even mixture. Use a paint stick to push it into the corners. If using the center piece on top (mold top down), lower it into place; there's a piece you can use a 2 by 2 to secure when glued into the center. Wait about 36-48 hours, wetting the exposed poured surface occasionally if needed. Then separate the mold. If you sanded well, used wax and non-adhesive caulk on mold mating faces, and applied good even cooking spray, the mold should come out easily enough. I struggled with the middle section only (but I made it thin enough to cut out). For the next 48 hours, keep wetting occasionally with a spray bottle (every 3-6 hours should be fine). Wait at least one week before painting; I used Valspar Concrete Paint and Primer in White, three weddings later with no complaints. Before painting, you can use concrete patch repair to level (add some adhesive they sell for patching concrete). Enjoy! Feel free to ask questions; it's better to learn from someone else's experiences if possible. This was only my second concrete project; I made a vase 1-layer perimeter mold as a practice piece using one of the examples on Thingiverse, then jumped right to this project. So, I wouldn't say it's incredibly complex.