I only played a small role in this project, but I’m proud to have been a part of it. I’ve worked with Fu-Tung Cheng, founder of CHENG Design and CHENG Products (ShapeCrete) for the past 4 years or so. I’ve learned a tremendous amount about concrete forming, casting, and finishing from a design and fabrication point of view, but it’s not very often that I need to model anything that’s very complex in the computer, so I was really excited about this project.
He designed the Moon Gate for his personal residence. It’s a 7 foot tall concrete portal with a copper swinging door, and the concrete is pigmented purple. I really love this.
A ‘knockout’ is a part of a concrete form that is removed after casting. Generally it leaves a void in the concrete and gives the piece its shape.
Working from his drawings I modeled the gate in Autodesk Inventor.
I delivered the .stl file to the local foam guy and he CNC routed the pieces from two large blocks of 2lb. EPS foam.
The knockouts are both the same shape, sandwiched together, a little bit like a TIE fighter.
After the foam was cut and delivered the ridges from the router step-over are sanded down and the piece is covered with a thin layer of plaster or something. A polyurea coating is usually used, but it was expensive and sometimes the long way around works just fine too.
You can see in this photo the supports for the swinging door that will be cast in the concrete.
The form has to be quite robust because there’s a lot of buoyant pressure when the piece is cast and a weak form will blow out and cause a little disaster.
After the piece has cured for a week or so, the form can be stripped, the foam removed, and finishing work can begin on the edges.
Awaiting the door installation:
Copper swinging door installed.
The finished piece:
Even though my part was small in this project, it was great to help Fu-Tung bring this project to fruition. I like seeing small shapes in the screen make the transition to full scale.