A brief history, in photos, of the steps that went into building the Balletmobile entry to the 2015 Baltimore Kinetic Sculpture Race. I could not have built Balletmobile without help from friends. Hopefully, my friends all know how much I appreciated their help, but I want to single out Renée Myers from Ballet Mobile, Inc., and Rod from Pedal Pushers in Severna Park, Md. (see links at bottom)
Words and pictures by Chip Walsh, all rights reserved.
Last edited May 19, 2016
|Cutting and grinding during February’s cold spell, I destroyed four junker bikes, turning them into bike halves.
|Lacking precision jigs, I made do with 2x6s and C-clamps.
|I tried to add the second tube near corners of the bike frame 'triangle,' which I felt would offer more support. But what did I know? I am not a bike builder. I was also teaching myself to weld while I went along and trying not to blow too many holes in the frame, which is easy for unskilled welders to do.
|The half bikes are connected with steel 1x2 tubes. Cutting the tubes to precisely match each bike's tubes was tedious and time-consuming. The seat stays from the blue Roadmaster were reused to support the ‘rack’ on the back.
|Riding the first assembled bike pair down the driveway, there was a frightening amount of wobble. It would not have made a very good tandem.
|A second pair of bikes was assembled and is here ready to have the frame painted. I only painted bare metal because I wanted the junker bikes to maintain their identity.
|A long chain, assembled from multiple chains, connected the large chain ring of the front and back cranks, so they would move together. By luck, the chain on the first bike pair was just the right length. The chain kept falling off the second pair, and I had to add a tensioner, salvaged from a discarded deraileur, to keep the chain tight.
|Here the two bike pairs are aligned for addition of the connecting beams. Using different bike frames made this more difficult because various frame components did not line up between the two bike pairs.|
|With the addition of the connecting beams, we had a basic, 4-seat, 4-wheel bike.|
|The first steering linkage had a turnbuckle allowing adjustable length. After many test rides, we thought we had zeroed-in the length and went to a more tightly fitted, one-piece tube. Steering continued to be an issue. The bars vibrated a lot and it felt like a fight to control the steering.|
|After consulting with boating friends, we decided to build the floats from foam insulation board and plywood. In the water, we planned to get off the bikes and ride on the floats, so I wanted them to be strong enough to walk on. The picture at right shows float materials prior to assembly.
Water weighs 62 lbs. per cubic foot. I guessed the sculpture and riders would weigh 1,500 lbs and I wanted each pontoon to be able to float all the weight, in case for some reason the weight all went to one side. I did some arithmetic and came up with float dimensions. The floats worked well. We were great in the water. The trouble is, the floats have to go with you around the whole course, and they weighed lots.
|We applied liquid nails construction adhesive between layers of foam. After every third layer of foam, we layered quarter-inch plywood. In retrospect, we didn't need all that plywood, and it adds a lot of weight. Furthermore, a year later I discovered the adhesive gets soft when wet, and it really didn't stick that well to the outer, foil layer on the foam boards. Fortunately, the water section of the race is brief, and the glue softens slowly.|
|Students and parents from the Ballet Mobile school applied art to the floats. This is what "visionary art" is about, right?|
|Susan Moore is a principal artist with Ballet Mobile and she drew this sketch of the dancer we dubbed 'Kitri'.|
|Tom Saddler and his crew at Metal Benders turned the sketch into a 3-D aluminum cut-out.|
|Susan and Renee, Director of Ballet Mobile, painted and decorated Kitri with authentic, ballet, flourishes.|
|KSR Rules require everything the team uses must be carried on the sculpture. For us, that included PFDs, water, and wheels. Lacking an effective suspension, we expected to 'taco' some wheels, so we carried extra. From fencing, I fabricated baskets within the cross beams.|
|Testing day: April 16. We took everything over to Centential Park, put it together and drove it around, including into the Lake. Onlookers looking for interesting youtube material were disappointed we didn't sink. After a lap of two around the Park, we concluded the Balletmobile was a better boat than road vehicle. We gave a lot of thought to what to use for the beams to hold the floats on. As seen in the photo, we finally opted for 2x4s.|
|The Race was postponed due to the Baltimore riots. We reasoned our team members all had the day free, so we threw a party. A highlight of the party was taking the fully assembled Balletmobile for a spin around the neighborhood. The kids thought it made a good jungle gym.|
|When I started this KSR project, I said I would consider it a victory to if we could just get to the starting line. I fully expected something to break at some point in the race, but I didn't know what I was doing and just pushed ahead—just get to the starting line. In this photo, Balletmobile sits at the start on Covington Street. Victory!|
|The race started. Here the team crests Federal Hill. The floats ended up weighing 130 lbs each, and none of us knew if we could push all that weight up this first hill.|
|We intended for Balletmobile's floats to ride 8" off the ground. While mounting the floats, we did not take into account the weight of the sculpture and the riders would fully depress the suspension forks of the front wheels. So, we lost an inch or two, which helps explain why the floats were plowing in the sand pit. We did not make it through the sand or the mud.|
Balletmobile completed the Race. Some of the safety kayakers told me Balletmobile was one of only two entries that made it through the water, and out of the water, without assistance. We had many compliments on our bribes (Kitri cookies) and our mini-Kitri sock puppet. We might not have been the best at anything, but we were good or very good at everything, so the judges recognized us by awarding us the "Fill in the Gap," aka, Judges Discretionary, Award.
I had a lot of help from friends including Rod at Pedal Pushers in Severna Park, MD. and the whole team from Ballet Mobile. Here are their links: