How to CNC machine a large statue in layers
Statue as prop for Hollywood movie The Games MakerDeskProto user Inchausti Parinelli Realizaciones in Buenos Aires (Argentina) is a Model Making company. They work for theme parks, marketing campaigns, and of course also for movie productions.
One of their clients is Pampa Films, a Buenos Aires based production company for national and international original full-length films. In 2014 Pampa Files created "The Games Maker" (or in Spanish "El Inventor de Juegos"), and they contracted Inchausti Parinelli to make a statue that plays an important role in this movie.
Banner advertisement for movie The Games Maker, in Spanish.
The main character in the movie is Ivan Drago, a boy who finds himself in the city of Zyl, where he needs to find an explanation for everything that happened in his life and with his family. In this quest he is assisted by the city's "Magical Brain", in Spanish the "Cerebro Magico", embodied in a large statue.
It is this 2.5 m tall statue that Inchausti Parinelli created for the movie set.
Design of the statue, in the Bonzai CAD program.
Pampa Films provided Inchausti Parinelli with a digital model of the statue, created by concept artist Pablo Olivera. The model was transferred as OBJ file (47 MB), and Inchausti Parinelli used the BonZai3d software (now called Form•Z jr) to convert his model to STL, which is the current de-facto standard for Model Making. The illustration above shows three shots of this STL file.
The STL files that were used: the complete face of the statue and an exploded view of the separately machined slabs.
The Starcam CNC router table used by Inchausti Parinelli has a limited working area in Z: maximum height of the model is 100 mm. The giant statue thus needed to be machined in slabs of 100 mm thick, to be assembled later. So the STL file needed to be sliced, what can be done in DeskProto by setting appropriate Part segments, see the illustration below (right side).
However, in the year 2014 Inchausti Parinelli was a user of the lowcost DeskProto Entry Edition, and this lowcost edition does not include the option to set Part segments. So they used the BonZai3d program to slice the model, and create separate STL files for each slice.
Our compliments for Inchausti Parinelli to complete this project with a CAM software license priced only 145 Euro !
DeskProto toolpaths for the third layer. First as Inchausti Parinelli created them in the Entry edition, next how it can be done in the Expert edition.
The parts were machined in 100 mm thick slabs of Styrofoam®: lowcost polystyrene foam, as used for packaging. In addition to the low cost a second important advantage of this material is the low weight of the resulting statue.
Machining one slab of polystyrene, and assembling the slabs to form one model.
The illustration above shows the Starcam machine with a slab of foam. As you can see on the right, many slabs were needed: not only for the front but also for the two sides (the ears). In this illustration the separate slabs still can be clearly recognized.
The resulting model is hollow: no need to fill the complete volume of the statue with foam.
The polystyrene was smoothed using lots of putty and sandpaper; next it was painted.
After glueing the slabs to form the complete statue, lots of putty (filler) and lots of sandpaper were needed to create a smooth surface. Or in fact not too smooth: the finishing emulates an old wooden surface.
Next the statue was painted, and electrical illumination was built into the two eyes (red eye lamps).
Click on the first image for a video about the production process, next the resulting statue.
Four of the images shown above are in fact stills from a video that shows the production process of this statue. You can follow the video link above to see this complete video on the Vimeo channel.
The Cerebro Magico statue in the movie.
The photo above is a scene in the movie: this room is where Ivan Drago visits the Cebrero Magico: a true mystical environment.
The movie has received positive comments:
"A wonderful mix of The Wizard of Oz and Harry Potter", and
"The creativity behind the characters' origins as well as their environment will appease viewers of any age", where this last remark does of course also apply to the Cerebro Magico statue !