Over the years my work has evolved into two distinct areas, design and production.

The design phase is composed of periods of drawing, "playing", and building. I do the initial drawings on a Macintosh computer. This gives me the freedom to easily change, rotate and resize any of the individual elements in a piece. I use a program called Adobe Illustrator for this phase of the work. It allows me to create flowing curves and undo my mistakes!

During the past few years the "playing" phase of designing has moved more to the computer also. I can now put together the parts drawings along with simulated bearings and springs and get a good idea if the concept will "work." I use a program called Working Model by Knowledge Revolution for this phase of the work. Often these drawings will be very crude, just some quick shapes to see if the basic idea is sound and moves as I had expected. I then add more detail as I get more excited. The limiting factor to just how complex the simulation can get is the speed of the computer. I don't try and simulate an entire sculpture, just the parts of the mechanism that I'm not sure of. The computer speed limits keep getting raised and playing keeps getting easier!

Screen Shot from Knowledge Revolutions's Working Model showing a patterning test for Phenomenon.

Working Model is a 2 dimensional program. If I want to see how things will look and move from a variety of points of view I have to transfer to a 3 dimensional program. My current favorite (I've tried a lot of these programs!) is called Extreme 3D by Macromedia. I can use it to generate fairly realistic animations.

Screen shot from Macromedia Extreme 3D used to generate 3D animations.

Even with all this computer help a new idea can still fool me when I actually try to make it. As the idea takes shape I print out full scale patterns and make up a model to see if the piece will work and move as I have planned and hoped. I'm getting better at it but there are still days when I wonder why I got out of bed!

Next follows a period of redrawing and rebuilding until the sculpture either succeeds or fails. This is the phase where the computer makes life a lot easier. I can redraw and reposition any of the parts and then instantly make up new full scale patterns.

A final design is usually the product of equal measures of planning, engineering and serendipity. A successful sculpture has to be entertaining and have an interesting motion. I have to be able to make it for a reasonable price and it has to be reliable. I also have to be able to ship it any where in the world and have people unpack it, set it up and operate it without problems.

The production phase is nearly as challenging as the design phase. Most of my sculptures are made in limited editions so the first step is designing "hard" templates and jigs. I have developed a variety of methods to reproduce the individual parts accurately and am constantly experimenting with new procedures and methods.

I usually make the sculptures in groups of six. I cut most of the pieces on a band saw and then do the final shaping with a table router and sander. All the holes are predrilled using a drill press. I cut and make all the knobs, pulleys, and spools by hand using techniques that I have developed. All the pieces are hand sanded and then stained and finished.

David cutting stacked wheels on the bandsaw.

The finishing process takes several days. I assemble and test each piece when the finishing is complete. This involves making final individual adjustments and balancing of all the wheels and levers. I mount and operate each sculpture for several hours to make sure it runs true. After several days of fussing, the pieces are packed and shipped. The most difficult part of this job is making the final decision that the sculpture is "just right" and ready for shipment.

Links to Software companies will open in new windows.

Working Model by Knowledge Revolution
Illustrator by Adobe Software
Extreme 3D by Macromedia