The RotoMAAK
The RotoMAAK
The RotoMAAK is a DIY Rotational casting machine to bridge the gap between rapid prototyping and the cost of producing thousands of hollow cast parts.
Rotational Casting, also known as Rotocasting or Hollow Casting, is a molding process for creating many kinds of items, mostly hollow in form and typically made of plastic. The RotoMAAK rotocaster was born out of the desire to have a process by which Makers could scale up production of parts using rotational casting technology when 3D printing a small production run becomes cost and time prohibitive.
HOW DOES IT WORK?
The RotoMAAK rotational caster consists of a hollow mold and a rotational device that spins the mold in a uniform motion. The hollow mold is filled with a charge or shot weight of air cure resin. It is then inserted into the RotoMAAK where it is slowly rotated (usually around two perpendicular axes) causing the liquid resin to uniformly disperse and stick to the walls of the mold where it slowly cures over time into the shape of the part. In order to maintain an even thickness throughout the part, the mold continues to rotate at all times during the casting phase and curing phase. The continuous rotation of the mold also avoids sagging and/or part deformation.
The rotocasting process was applied to plastics in the 1940’s, but in its early years was rarely used due to a slow process and restriction to a small number of plastics. Over the past two decades, improvements in process control and developments with air cure resin and plastic powders have resulted in a significant increase in its usage for part production.
OUR INNOVATION:
The RotoMAAK rotational casting machine allows the hobbyist to experiment with different casting materials and mold creation for production scale-up of parts to meet customer needs. With the popularity of DIY 3D printing, you now have the ability to create a 3D object in a relatively short amount of time compared to the traditional prototyping or one off manufacturing processes. 3D Printing allows you to create one part faster than traditional processes, but not reproduce it as quickly as mass manufacturing technologies. With rotational casting, you have more options to reproduce many identical parts from a successful print.
Additionally it is not limited to 3D printed molds (NO 3D Printer required), you can create a mold from almost any part and in turn reproduce multiple replicas of that item.
ADVANTAGES:
One of the major advantages of rotocasting a hollow part is the savings in materials and weight. If a part’s function does not require it to be solid, why cast it solid and waste materials? Instead of using pounds of material to cast a solid piece, you can cast it hollow with ounces of resin, which in turn yields a big cost savings in time and material.
The RotoMAAK also controls the rotation of the mold to ensure a uniform wall thickness that rotating a mold by hand cannot achieve. Some air cure resins, especially the clear varieties, have a cure time of several hours instead of 6-10 minutes. Evenly rotating a mold for hours would prove to be impossible by hand, and a rotational machine like this will allow you to rotational cast clear bottles, glasses, etc. for amazing special effects.
MARKET:
First we are looking at ways to increase the speed of reproducing 3D printed parts, by either using a mold that was 3D printed and cast directly from that, or by 3D printing your part and creating a silicon mold from that. However, after talking to many people at Maker Faires, other Makers and hobbyists in the community, and others with manufacturing experience and creative tendencies, we have identified even more niches and applications for this technology than we first envisioned. Many different people: doll makers, artists, moldel makers, and action figure enthusiasts, can go from clay original to silicon mold to producing and selling limited edition reproductions. Candy makers can make custom and personalized hollow chocolate figures, even people making R2-D2 replicas with hollow parts that have been cost prohibitive to have machined. Custom bike builders can even rotational cast specialty/themed turn signal lenses.
MACHINE SPECS:
* Motor speed: Variable to 14 rpm
* Voltage: 12v dc gear drive motor with planetary gear reduction
* All pivot points and axes have 608 bearing for long smooth life
* Precision Laser Cut Parts
* Mold Max Size Capacity: 12” x 11 1/2” x 11 1/2”
