Sometimes, the best innovations come from a driveway, a few plastic tubs, and a lot of curiosity. That’s exactly what Steve Ciervo at Kawi Performance proved with his first-ever investment casting experiment — turning a 3D-printed STX trim nozzle into a fully functional aluminum part. And yes, it’s every bit as wild as it sounds.
The experiment began modestly enough. On a cement driveway, Steve laid out two “shells” — hollow forms created from 3D-printed models — alongside buckets of Remasol Adbond JusDip and tubs of fine and coarse casting sand. With a paintbrush and a generous dose of optimism, he began dipping the shells in a neon-yellow ceramic slurry, then rolling them in fine sand to form the first layers of what would become a strong, heat-resistant mold.
“This is the first time I’ve ever done an investment casting,” Steve admitted as he methodically worked on building out the forms — dipping, flipping, sieving sand into the hollow cavity, waiting for each coat to dry “And it’s really messy, as you can see,” he added, with fine sand clinging everywhere.
After multiple coats and days of drying, the shells were ready for their smoky transformation. Into the kiln they went, hollow side down, cut and scraped to let the plastic burn out completely.
When it came time to pour, the experiment entered the “have 911 on speed dial” phase. Aluminum melted in a small furnace, skimmed to remove impurities from a mix of scrap parts — valve covers, fuel rails, and other bits of aluminum lying around the shop — and then carefully poured into the ceramic molds that were super-heated to keep the solidification slow and allow the aluminum to fill into all the nooks and crannies.
Protective gear was a must — thick leather high-cuffed gloves, boot covers, and a duster/apron (worn over shorts, in true PWC style.)
Finally, the moment of truth: chipping away the ceramic revealed a textured, bright aluminum nozzle.
“I can’t believe this came out of a plastic 3D printed mold and actually is a real-life working model. How freaking cool is that, guys? That’s sick. Very sick.”
With threads, mount holes, and trim fittings machined in, these nozzles were ready for action. The process may have started as a playful experiment, but it ended as a fully realized demonstration of ingenuity, persistence, and a touch of controlled chaos — the kind of project that reminds you why we love tinkering with personal watercraft.
Kawi Performance continues to push boundaries, and this first attempt at investment casting shows there’s no limit to what Steve and his team can dream up — even if it involves setting 3D prints on fire in the driveway.
