CARTHAGE, Mo. —
Randy Ridings ruined the perfect name for his invention. He had invented a vehicle that combined a tricycle with a kayak. The words combined for the perfect name: A triak.
But he had to add a fourth wheel, meaning triak no longer worked.
So how about "quack" for the four-wheeled kayak? No way. He's going with "quayak."
"If you look up 'quack,' you'll see all kinds of stuff," Ridings said. "But with 'quayak,' it's just me."
Ridings is the only one with such a vehicle, and will likely remain so for a while. In the spirit of hovercrafts or amphibious tourist vehicles that travel from highways into lakes, Ridings' vehicle can be pedaled straight into waterways such as rivers, creeks and lakes.
It was inspired by his love of kayaking and his annoyance of lining up transportation details just to go kayaking.
"I've always had the opinion that there's a flaw in the system," Ridings said. "If I went to go kayaking, I had to go down river and have someone pick me up, or hire a pickup service, or talk a friend into coming along. For years I did that."
The solution for this problem lay in one of his other favorite activities: Bicycling.
Inside a quayak
Ridings' quayak combines the shell of a kayak and pedal-based locomotion of a bicycle. A set of pedals powers two large wheels in the front, and handlebars steer the vehicle by controlling two smaller wheels in the back.
On land, the vehicle works just like a bicycle. Ridings pedals, it moves. He has a transmission that lets him shift just like he was on a mountain bike, so he can keep a brisk pace.
Converting the vehicle for water requires no adjustments or transformations, however. Similar to the paddle-wheel steamboats of the turn of the century, the front wheels of Ridings' quayak are equipped with paddles.
The back wheels feature another ingenious detail: Covering the spokes are large plastic discs that transform the wheels into rudders.
With his adjustments, Ridings has the maneuverability of a canoe. He won't speed down a river, but he can float with no problems. And when he's done, he can ride back to his launch point without the need for a pickup or complicated plan for moving cars.
"I've done trips where I leave a bike at one end," Ridings said. "I call those trips 'surf and turf.' I'm glad I figured out how to solve that problem. When something is in front of me, I can't leave it alone."
Ridings is pretty happy with how his vehicle performs. He said that he may not be able to go as fast as a kayak, but the minimal exertion of energy used to pilot the quayak enables him to stay on the river much longer.
Ridings has made adjustments to his initial design. Sheets of corrugated plastic fit over the wheels to control water jets that the paddles push up. More corrugated plastic has been folded and sealed to make pontoons along the sides.
From a distance, the colorful patchwork of the quayak looks like it could have been thrown together with spare parts in a junkyard. But the heart of the quayak is an intricately designed differential, custom built by his father, Jim Ridings, of Oronogo.
Ridings thought up the entire vehicle concept and built a small model with PVC pipes and plastic sheets.
"I'm not a graphic designer, or good with CAD," Ridings said. "I had to build it. That gave us a really good idea how much steel we'd need, what angles we'd have to work with."
From there, Ridings consulted with builders of human propelled vehicles. Through Internet forums and message boards, he got some good, practical advice on what to build.
"Those guys focus on racing," Ridings said. "But they were really positive and helpful. They said it would be a pack mule, but it would do whatever I wanted."
So he took the plan to his father. Jim Ridings is a retired engineer for Eagle-Picher, who worked for the company during its space-age glory days, Ridings said. Now a cattle farmer, he still has a shop filled with tools for heavy-duty craftsmanship.
Jim Ridings took one look at the design and saw a key problem, Ridings said -- he couldn't accommodate a differential, the system of gear switching.
Heading back to the drawing board, Ridings found designs for double differentials similar to what cars use, and proposed another idea.
"He looked at it for 10 seconds, and said, 'Sure, we can do that.'"
The solution called for creating a heavy-duty axle system and other custom parts. Ridings said his father built a complex, sophisticated transmission component, complete with two disc brakes, that fits in the space of a kickball.
"It's a marvel of engineering," Ridings said. "I had ideas of where we wanted to go, but my father's engineering and fabrication skills are what made this happen."
Construction started in March in his father's shop. Built on his old kayak, they added the wheel frame by cutting some holes in the top of the kayak's shell. No holes are cut below the water line.
Still, water gets in, but nothing Ridings can't handle with a few large-capacity sponges. He also has converted the pump of a caramel dispenser into a handheld bilge pump.
And the design is continually improving. The first version had three wheels, but steering problems led to experimenting with a fourth wheel. Ridings also wanted to maximize land speed.
Now, Ridings is working on the vehicle's paddles, so that he can go faster in water. But adjusting paddles is tricky, he said. For them to work, they have to hit the water at a specific angle. Too shallow, and they don't push enough water. Too deep, and they push water downward, not behind.
In order to learn more, he's asked for advice from paddle boat captains.
"As it turns out, there's no real formula for paddles," Ridings said. "Each captain said they build whatever works. Each hull design and paddle works differently."
He's also working on cargo platforms that would double as aerodynamic aids.
Ridings said he has no current plans to market his vehicle. Unless some rich billionaire throws money at him, he'll keep working on his own vehicle, improving his design.
But he sees potential in his quayak, as evidenced by his thoughts about the name.
The vehicle could become popular with tourists who want to explore natural areas by both land and water. Another application could be as a rescue vehicle -- a fit swimmer could use the quayak to maneuver to places where a Humvee or boat could not go. It would be perfect, Ridings said, for flooded cities with rolling hills.
But his immediate plans include working on his vehicle for rides. In September, he plans to take a 400-mile trip across the Katy Trail, plotting a route that takes him over pavement and waterways.
He'll also build at least one more quayak in the future, for his 10-year-old daughter. Right now, his designs are built specifically for someone's height and weight, because of the issues relating to balance and paddle propulsion.
"It's on the list to build her one," Ridings said. "I need to wait until she's past her major growth spurt."
After that, they'll hit the road. Or lake.