Whether you’re modelmaking for an industrial design studio or a movie set, foam is a go-to material for creating large, fake objects. It’s a fairly economical way to build up mass.
However, foam can be messy and time-consuming to work with. You of course need a skilled artisan to sculpt it. The larger you go, the more you may need to add steel supports for structure. Then there’s the finishing; if your large-scale object say, needs to withstand fake rain on a movie set, the foam will require laborious finishing, sealing and sanding.
Australian modelmaking shop Studio Kite knows about all of these problems. The company has been around since the ’90s, and you’ve likely seen their work; they created that organic battery bank that Neo wakes up in The Matrix.
In 2000s they began experimenting with 3D printing using a robot arm. Steve Rosewell, the company’s Principal Engineer, designed the system but wanted to go bigger. He subsequently developed Cadzilla, a gargantuan 3D printer that resembles an elevator shaft.
In designing the machine, Rosewell initially looked at the 3-arm delta configuration, but found it too imprecise. By adding a fourth arm, he not only increased accuracy, but resolved the build area into a more convenient square footprint.
Incredibly, the machine can print objects 8.5′ square and nearly 12′ tall (2.6m square, 3.6m tall). Internal support lattices can be baked into the designs, obviating the need to add internal bracing later.
By focusing on the design of the nozzle, Rosewell created another advantage. It features a vibrating plate that flattens the extruded material as it deposits it. This means that as each layer is built up, “we’re not putting a round bead on a round bead,” Rosewell explains. “We’re actually putting a ribbon on a ribbon.”
“We can have that ribbon maybe 8mm wide, but only going up 1mm. That means our overhangs can really reach out a long way.”
Printing in thin ribbons like this means quicker cooling times, and the finer connection between the layers means there’s less time spent on finishing. And robust, outdoor-safe finishes can be achieved. “Parts can be finished with a water-based acrylic modified cement material which is weatherproof and tough,” the company says.
Another brilliant part of the design: Rosewell designed the Cadzilla to use pellets for feedstock, rather than filaments. This provides two benefits. The first is that pellets can be purchased in bulk for less cost than filaments. The second, is that if a design doesn’t come out right, the team can simply grind it up, then dump the grinds into the hopper for a second go-around. This greatly reduces waste.
The Cadzilla can print with ABS, PE, PP, PVC, PLA, HDPE, and TPE/TPU rubber.
The company says they plan to bring Cadzilla to market.
Here’s a look at the machine, and what it can do:
