Alameda County Exhibit - Page 1 | 2  

The Alameda county display was designed to have several boats slowly making their way around a 12" wide channel of water.

I spent the majority of my time at the fair this year building the Alameda county display.

The channel was made by dropping a triangular island into a shallow pool. I mounted a powerful pump in the center of the island, and built a small manifold (splitter) to distribute the output into the three separate hoses. 

The hoses thrust water around the pool, and the pump pulls it in from the center.

Toy boat kits are available, so I built a few of them for the channel. Only when they were finished did I discover that the wooden boats were barely buoyant enough to survive the turbulent water.

The little boats were also dwarfed by the rest of the display, so at Richard's urging, I began experimenting with longer boats made of styrofoam instead of wood.

This photo shows a chunk of foam we were using as a test boat. The large size looked good, so we decided to scrap the tiny boats and build five larger boats.

To the left of the water channel, a tower of the Bay bridge rose up into the air. Alameda county is on the east end of the Bay bridge.

In this photo, you can see the center island tipped up against the background.

I cut out and assembled a cargo ship, a pleasure boat, a tugboat, a ferry and a sailboat. The cargo boat was the longest and the ferry boat had a blunt front end. These small differences in the hull shapes gave me fits when it came to keeping the boats moving.

The display featured four layers of plywood, cut at the top to look like various landscapes of Alameda county. There were mountains, hills and city, spatter painted in gold, green and blue.

The blue background, leaning against the paint cart.

Closer to completion.

The boats usually went around the track with ease, but they would get hung up from time to time on the corners. I spend an awfully long time troubleshooting the boats. I tried making the water go faster, adding fans, adding keels, adding water and rounding the corners of the channel. I repositioned the water jets and coated the sides of the channel with cellophane tape.

It was frustrating, because the effects of little changes were hard to test... unless the boats stopped immediately, it was hard to tell if the latest modification was having a positive or negative effect.

Finally, two days before the fair opened, the boats went around all day long without stopping once. I was thrilled.

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