March 2009 - There's a certain cool factor in being able to climb walls like Spiderman. In fact, there are people who have been doing this using steel walls and magnets for some time.

But they had to overcome a lot of obstacles, such as when to place a magnet on a wall and how it will act to a person's movement. Also, the right magnet can have plenty of holding power, but as soon as you try to put downward force on it, it'll slide rather than stay in one place.

After years of developing a successful entertainment system, Spider Climbing Inc., Ann Arbor, Mich., has overcome these obstacles.

"The company started because a good friend of mine who teaches physics came to me with an idea," says Dave Barnes, president of the seven-year-old company. "He always had an idea to climb steel structures using magnets. It started out as a physics project. He showed me a video of his class trying to climb a 2-ft.-by-4-ft. sheet-metal wall, and the kids were climbing all over it. I thought it was hilarious, but the cool factor was high.

"He asked me if my company that sold science equipment to schools would be interested in developing it. At this point, it was more conceptual, but I helped him with it. Finally, I started spending so much time on it that if we were going to commercialize it, I wanted part of the company."

From the point Barnes and his friend went in together on the business, it took about a year and half to make the concept functional enough to commercialize it. With the first sale of a system in 2005, it's been an ongoing process to improve it.

"We were lucky enough early on to go to a trade show put on by the [International Association of Amusement Parks and Attractions]," Barnes says. "We exhibited our concept and got a handful of initial customers who understood the concept and purchased them for parks and science museums. We had real-world R&D to get instant feedback on the system. It was definitely a learning process, because no one had ever done it before."

Hitting a wall
Barnes says the company had issues with the system because it works with aluminum and steel for some of its equipment, along with rare earth metals, for the magnets, and they all had to work together properly--they didn't at first. Then there were challenges with the climbing walls themselves. The company could build a steel wall, but it weighed 4,000 lbs. It had to be lighter and modular so the components could be shipped easier and at a lower cost. The company also had to figure out how to take a large wall superstructure, put it in crates and ship it. The company also had to design it so that it could be put together without having an engineer on-site.

"We had bonding issues with the climbing gear," says Barnes. "We have a custom magnet made for us and it uses neodymium. There's only one place in the world we can get this--China--and we had issues getting the neodymium alloy right to get the proper magnetic field strengths we needed. At the same time, we were going through a patent process on everything."

"Most people who have used magnets for climbing have employed electromagnetic systems. This system is effective but not cost-effective. You have to press buttons to engage and disengage the system while you're climbing. It's not simple. There are circuitry and mechanics of making this work that cause it to be incredibly expensive."

"Our vision was to use the basic rules of physics. We wanted to make this work without any buzzers or buttons but just the natural movement of the human body. We perfected it and patented it, but we had to learn a lot of things about friction and the forces that needed to work to have a functional system."

Some of the challenges Barnes came across included whether a child and adult could use the same magnet.

"We make four magnetic cartridges," he says. "We just change the placement and quantity of magnet material to take care of the various lift capacities we need. Our cartridge system allows us to control the magnetism for a child and up to a 250-lb. adult. It's how we configure them within the climbing gear that allows us to do different weight capacities. We had to control the shearing forces, the weight of the body being acted on by gravity and then the magnetic field that engages the steel. We worked on the friction coefficient between these two."

"We needed a sufficient magnetic field to carry the weight without letting the person slide," he says. "We stopped side slippage by using a polyurethane coating. We had to come up with our own molding process because within the polyurethane molded pocket are magnets that have to be bonded to an aluminum plate, and the entire assembly has to be placed in a polyurethane shell. With this setup, if you try to pull straight away with our magnets, you can't do it. But you can peel them off, which mimics the natural motion of the body."

Striking a deal
Although Barnes and his partner had the idea of how to do this, they didn't have a metal fabricating facility to make the steel climbing wall and steel framework to support it.

Barnes came across Storch Magnetics, Livonia, Mich., a steel fabricator with its own product line. It was a perfect match because the company has many years of experience producing magnetic conveyor systems and magnetic assemblies for industrial applications. It has a Mitsubishi CO2 laser that was used for the precision cutting that Barnes demanded for the Spiderwall system. Barnes found Storch also had a better source for his magnets. "It turned out to be a great partnership," he says.

To build the Spiderwall, Storch Magnetics uses a jig to build the framework using 1-in.-by-1-in. peripheral 14-gauge tubes and 1-in.-by-2-in. 14-gauge stringer tubes mounted behind the 14-gauge steel plate that's used for the climbing. Then it welds the steel plate wall panels, which have to be perfectly square to the framework. For the bottom framework that supports the overall system, Storch uses10-gauge, 2-in.-by-2-in. square tubes. After constructing the frame, the pieces are either welded or bolted together.

"The frame stays with the sheet steel," says Barnes. "We have a vertical and horizontal system. Our vertical system is more popular. You might think you have to go high to be exciting, but actually the long wall horizontal is more in demand. We have a number of struts that attach the 4-ft.-by-4-ft. sections together. It's simple. The verticals are more involved, averaging 20 ft. to 25 ft. If you're thinking about going upside down, you can't. The forces change and the vectors of the magnets change, but you can climb a slight incline, like that of a ship's hull."

Who would have thought that climbing like Spiderman could be such fun? FFJ