Flexi-Moulds for Concrete Dominoes

myminifactory

Printed game pieces can feel a bit too light but we can fix that! Let's step back for a moment and think about what you can do with flexible 3D prints that you can't do with more conventional stuff? It turns out that one area where flex really shines is in molding rigid materials. Rigid molds are fine if the content has a bit of elasticity, but for something like concrete it's a huge pain! Even the fine texture inherent to FDM printing clings to the supremely solid cast interior. So, concrete dominoes! Let's just mention one thing here - concrete isn't really ideal for relatively small castings like this. Something like plaster is undoubtedly superior. Except... it doesn't sound as cool as concrete! The Molds Right! So, I went through quite a number of approaches to the molds themselves and in the end I discovered that very thin walls were just fine and allowed for easiest release of the cast object afterwards anyway. Also, this meant that the molds were quick to print and used very little filament so I just modeled molds for all 28 standard pieces. Originally, when the molds were more complex, I had a modular approach that used fewer printed pieces but there's really no need for such fussing around. Now, printing was... interesting. If you already print with flexible filament, you won't have any issues. However, I had endless problems getting 28 good prints done. I worked initially with a "flexible PLA" but warping was ridiculous even tearing itself off a few solid layers of regular PLA I tried laying down underneath! In the end though, I had good luck with TPU and it proved to be nice and strong too when I stretched the molds open to release the pieces. Casting If there's one thing that's really, really important it's this: Always use a releasing agent! What is a releasing agent? Basically something to stop the concrete sticking permanently to the mold. Canola oil, ideally just plain old canola cooking spray, is amazing for this. I was able to just push my cast dominoes out of the molds with no breakages or problems. If you don't have that, you can probably use most oils as long as they don't have some incompatibility with your concrete. But Why? I just really love finding the things that 3D printing lets us do that we couldn't do otherwise. And precision concrete casting is just plain cool!