Giant Kinetic Praying Mantis Sculpture From Found Materials

I have always felt that the Praying Mantis is one of natures coolest creatures. As a sculptor, this insect proved to be the perfect inspiration for my latest project. I hope the community here will forgive me if this project is not necessarily the sort that is easy to duplicate. I have posted it here as a way to share the steps that go into my sculptures and to promote discussions about building things, creative reuse and fine art in general. As I will demonstrate in the following steps, this sculpture was made out of 99.9% found and salvaged materials. Even in instances where you see machined aluminum, know that it was scrap yard salvaged or pulled from the carcass of a larger machine somewhere else. This is also true of all wire, bearings, switches etc.
If you like what you see, please consider visiting my website to see my portfolio of other similar work.
Thanks!

Step 1: Parts Selection and Layout

I usually begin each of my pieces by arranging various found parts on the floor like a jigsaw puzzle until I start to see a shape that I like. In this case I had already collected a number of objects that I hoped would add up to a Praying Mantis. The main basic elements were: a pair of gas pumps to be made into pinchers, a set of four curtain rod brackets to be used as leg elements, a propane tank for the body, a hanging lamp for the abdomen, and the arm from a scroll saw to form the upper body.

Step 2: Pinchers

Since this piece basically began in my head with the discovery of the gas pumps I decided to start there. I also realized that this could potentially be the most complicated mechanical aspect of the project so it made sense to get it roughed out quickly to determine if my concept was going to work. The idea was to combine the gas pumps, curtain rod brackets, and some drafting table parts to mimic the design of a backhoe arm. The intended effect was to be part earth moving equipment, part insect.

Step 3: Fixtures and Mounts

As eager as I was to test the front arms, I had to finalize how some of the main body parts would fit together first in order to get everything to the point were testing it would be possible. One major hurdle was how to attach the scroll saw arm to the curved surface of the propane tank. This connection also had to be removable to make servicing and transport of the piece possible.

Step 4: Wings

Since the basic pincher test went well it was time to move on to the next puzzle. The wings. I knew that I wanted to use halves of a street lamp cover, but I had not decided if it was worth the trouble to make them move. The discovery of the "kneading" mechanism from a massage chair at the dump helped me make up my mind. This mechanism produced such a perfect elliptical rotation that I had to give it a try. While this saved me trouble of designing the moving parts, it presented me with the challenge of integrating it into the gas tank and connecting it to the wings.

Step 5: Head

In the research phase of this project I looked at a lot of photos of Praying Mantis's. They have very small heads relative to their bodies, and nearly all of this small area is taken up by their eyes. I wanted my sculpture to maintain a likeness to the actual creature but still convey a lot of character. This would mean the Sci-Fi inspired trick of evil glowing red eyes. I selected some brass wide angle peep holes from apartment doors. With a single small LED placed behind the lens I got the effect I wanted. They were then mounted via black plastic into the bag attachment portion of old Kirby vacuum cleaners.

Step 6: Final Assembly

The title of this step is a little misleading as it did not signify the completion of the project. In order to move on to the actual final step, the electrical work, I had to be sure I was done with all the welding and cutting. Once motors, switches and wires are involved it is no longer safe to add the heat that welding requires. So, at this point I had to shift gears and settle on how to build and attach the legs, and mount the motor that would drive the front pinchers.

Step 7: Electrical System

The only truly off-the-shelf part that went into this project was a little timing relay. In years of building kinetic sculpture I have learned that people cannot be expected to understand that they have to turn something off when they are done with it. To preserve the life expectancy of these pieces I came up with a system (with a great deal of help from my friend CTP) where the viewer presses a button to activate the motors. The piece runs for a few moments and then turns itself off. While this system is relatively very simple, it adds to the complexity of the final wiring. Since I am an artist and have no training in electrical engineering I have had to come up with a notebook full of "maps" of how to put different systems together. I have included a scan of the basic design which went into this piece as well as the relevant parts numbers for different suppliers of this particular relay.

Step 8: Its Alive!

At long last the beast is up and running! In general I am very pleased with the way that everything worked out. I feel like the sculpture is a good balance of menacing and delicate, two things I try to keep in nearly equal measure in my work. I hope that this instructable has been enjoyable to some of you. If you did like this project please visit my website: www.nemogould.com to see my full portfolio.
Thanks.
P.S. thanks to Siblia Savage for the classy final photos.