The Suprematist Time Keeping Machine |
The idea of this clock started during a visit to the National Art Gallery in Washington, DC. In the modern art section, there is a sculpture created in 1915 by the French artist Ivan Puni (1894-1956). Puni was an artist following the Suprematist art movement, very popular in Rusia. Below the pictures that I took at the gallery:
Suprematist Construction Montage
By Ivan Puni (1915-1916)
When I saw the sculpture, the idea of a clock came right away. The black circle will long rectangle as the second's hand, the long rectangle in the red square the minute's hand and long polygon on the black triangle as the hour's hand. The artist used cardboard, paper, and some scrap metals to make the sculpture, some of the paint is fade out by the time. The sculpture is protected with a transparent plastic cover to protect it.
My clock is a replica in the size and shapes of the original sculpture, but I used some other materials for durability and modern construction techniques. I used for the back place 1/4" plywood and dark Danish Oil stain. There is another inverter L shape piece that I think is some kind of stone in the original art, I used MDF with a smoke gray paint. For the square, triangle, minute's, and the hour's hands and circle, I used 1/8" plywood. The second's hand is aluminum.
I built the large cone shape with a brass sheet, the smaller cone shape with a sheet of galvanized steel, and the corrugated panel with an aluminum sheet.
I used for all the wheels, except the motor pinion 1/4" and 3/8" Premium Baltic Birch Plywood B/BB Grade.
The clock drive is a stepper motor controlled by an Arduino Nano with an RTC (real-time clock) and a micro-stepping stepper motor drive board. The stepper motors are noisy when running at low speed, even with micro-stepping, so I isolated the motor with rubber spacers and also made a rubber pinion to drive the clock.
All the wheel shafts are 1/4" brass, and all are installed with sealed roller bearings.
Creating the Model:
First things, first! And the first thing is the model, and as usual, I used Fusion 360 to create the 3D model of the clock.
I found the dimensions information on the National Gallery website and started my model with a canvas image scaled at the real size. Below you can see an animation of the transition from the canvas picture to the model:
Many hours of work resulted in a model almost identical to the original. There is some small modification in the position of the hour's hand to avoid collision with the minute's hand and to reference a real-time relation between the hours, the minutes, and the seconds. The artist made the sculpture in a way that it almost shows a real hour!
The clock body and decorative parts:
The wood parts were simple print paper templates and cut, the challenging parts were the metallic cones and corrugated sheet.
For the cones, I molded in Fusion a wooden molding base with the shape, I milled the molding bases in my router using a 3D contour toll path.
For the lower cone, I made the base in 2 parts and then glued them.
Once the base was ready y made a cardboard template to cut the metal. The slowly manually bent the metal sheet around the molding base and glue it to the wood with epoxy. In the original sculpture, the inside the cone is filled with wood.
For the brass cone, I made a molding base with 3 parts like ribs that I used to bend the brass. I glued the brass cone only to the center rib to keep the shape and to fix it to the back panel.
With the help of my son, some Photoshop, and some practice with the airbrush I was able to create the effect I wanted in the corrugated aluminum.
The wheel Train:
One of the challenges in this clock was the design and calculation of the wheel train. The position of the hands is fixed so I needed to make all the calculations with those distances. The other condition was to find the correct gear ration between the stepper motor and the second's hand to simplify the Arduino program.
A 1.8° degree stepper motor needs 200 pulses to make a full turn. The RTC device outputs a 1HZ square wave, the idea is to make the second's hand a full turn each second. To avoid the use of none-integer numbers, the best solution was to make a 3:1 ration to use 600 pulses per second. In the end, the stepper motor pinion is 8 teeth and the second's wheel 24.
Some extra calculations with the help of parametric sketches and my clock wheel train calculator Excel spreadsheet did the rest.
Next step was to create the toolpath for all the wheels and pinions and process them in the CNC router
Once everything was in place, it was time to test the clock at fool speed yo smooth the gears and enjoy the time passing.
I also tested the new laser head to engrave a nameplate for the clock, in this way the visitors of to ma son's new house, learn a little bit of the clock origin.
I enjoyed and learned a lot making this clock, especially after two years I made the last one!
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