Monday, July 21, 2008

Pedals on the Pedal Tractor


This weekend I put the pedals on the pedal tractor. I also figured out a way to take the sprockets off the crank sets and replace them with tiny, 15-tooth sprockets. It looks pretty silly but I need to gear down a lot in order to make the pedal tractor easy to ride. With these small sprockets on the front plus the gearing in the back, it should take almost four complete rotations of the pedals for each complete rotation of the six-foot diameter drive wheels.

Today, I took a little time away from real work to make a tray that sits between the rear seats. This tray can hold drinks, etc,. and it also protects the main shaft gears from the weather.

The next project is to remove the big wheels, rig rear brakes, put the gear on the main shaft and put it all back together. Once that is done, I can put the chains on and we might even be able to do a test drive at that point. I am still getting shoes for the big wheels. I think I only need four more pairs.

Saturday, July 12, 2008

Pedal Tractor Progress Report


The extended bicycle frame was welded to the main axle housing a couple of weeks ago. Last week I made the jack shaft and mounting brackets separately and then today I welded the assembly to the main axle housing. I designed adjustable seats out of two old plastic chairs. I mounted the seats and put the three bicycle freewheels and a small main drive gear on the jack shaft. The gears and freewheels aren't locked down yet. I need to make the pedal parts and then I can lock down all the gears after I line everything up.

Below is a photo of the jack shaft mounted to the main axle housing. The jack shaft is 3/4 inch diameter solid steel. The main axle is 1-inch diameter sold steel. The main axle housing is 2-inch schedule 40 pipe.

The main shaft is a solid axle from wheel to wheel. This is turning out to be a problem. It's really hard to turn the tractor with both big wheels locked to the shaft. I think I will have to cut the shaft and make it a one-wheel-drive pedal tractor. The other big wheel will just roll along. I am contemplating putting splines on the inside ends of the split axle and then making a spline sleeve that I can slide from the drive axle over the free axle in case I need two-wheel drive.

There is still a lot to do. There will probably be a lot of bracing needed. I won't know exactly where until we give it a test ride and see what's too flexible. I also want to weld on cup holders,
umbrellas and shade canopies for all riders, and maybe mounting brackets on the back for a sound system or maybe fire cannons?. Then will come paint, decorations, and maybe lighting for night travel.

I'm not the only person making strange pedal-powered tricycles. In fact mine is fairly tame compared to the ones made by a group of people who call themselves the Department of Spontaneous Combustion. They have made some three-wheeled pedal powered vehicles that shoot fire. Some of these have two big wheels in front and a single wheel in back. See a smaller one here.
And this is a link to a spectacular photo of one of their large ones.

Wednesday, July 2, 2008

Lawn Chair Larry

Today is the anniversary of Lawn Chair Larry's famous flight.

On July 2, 1982 in San Pedro California, 33-year-old Vietnam veteran Larry Walters filled 45 weather balloons with helium and tied them to a lawn chair. He floated quickly up to about 16,000 feet. To descend, he shot some of the balloons with a pellet gun. He landed in some high-voltage power transmission lines but did not get electrocuted. After hanging there for awhile the fire department got him down. This is not an urban legend. It's true!
More info on Larry's flight

Larry inspired others to imitate his craziness. In 1984, pilot Kevin Walsh tied 57 helium balloons to a chair and floated above Massachusetts for awhile. When he was done sightseeing he cut his lines and parachuted to safety.

In 2007, 48 year-old Kent Couch tied 105 balloons to a chair and floated 193 miles across Oregon. He was trying to make it to Idaho He also landed safely.

In April of 2008 in Brazil Roman Catholic Rev. Adelir Antonio de Carli tried the same trick. He tied hundreds of helium-filled party balloons to a chair and quickly ascended to almost 20,000 feet. It didn't work out for him. He is still missing. More info and photos.

These guys were definitely adventurers in the Zone. They aren't the only ones doing this either. Check out this website.

Below is a photo of Kent Couch floating somewhere over Bend, Oregon.