EDMONTON, Alta. – Two horrific highway accidents involving tractor-trailers in the late-1990s got the wheels turning in Dennis Mottershead’s imagination.
An engineer by trade, the Edmonton resident set out to try his hand as an inventor and put a stop to wheel-off accidents.
“I was watching the news one evening and there was a story about a wheel coming off a trailer and hitting a Buick, killing one woman and injuring the other person inside the vehicle,” recalls Mottershead. “About four days later, in Ontario again, I heard another tractor-trailer carrying cows had its two back wheels come off, tip over and there were dead cattle all over the highway.”
Mottershead went to bed that night and awoke the next morning with a new purpose. On his way to work the next day he picked up some studs and let his engineering mind go to work.
Before long Mottershead had developed a wheel nut locking device, designed to eliminate the need to re-torque wheel nuts and reduce the number of wheel-off accidents on the road.
To lock the wheel nuts in place, Mottershead engineered a socket to cover the nut with a dome cap to lock the socket in place. But some adjustments to the stud were required to fasten it all together.
“The first thing we do is machine the end of the stud and then we drill into the end of the stud and thread it,” explained Mottershead. “Then we needed a way to keep these (the socket and dome) from flying off, which is why we drilled and tapped the end of the stud.”
A bolt is then placed through the top of the dome and into the threaded stud, to lock all the pieces together.
“You can see there’s a nylon mark on the screw that makes the bolt shake- and vibration-proof,” Mottershead told Truck News.
The dome of the wheel nut locking device is adorned with red indicators as well, to give a driver some indication if there is a problem.
“The red indicators will give you an indication if the studs are breaking, because we know these won’t get loose,” added Mottershead.
Mottershead began development of his product in 1998 and has had the unit tested at Waterloo University; and patented in Canada and the US.
Mottershead then teamed up with John Perrotta, owner and president of J.Perrotta Trucking in Edmonton, to have the device road tested.
“I knew Dennis from before and said, ‘Hey, I’m in the perfect position to help since I own a trucking company,’ let’s try it out,” said Perrotta.
Perrotta operates a 22-truck and 30-trailer outfit of mostly 53-foot tridem drop-deck trailers.
Perrotta installed the wheel nut locking device on all three axles of one of his trailers and during its use, Perrotta never had to re-torque the wheel’s nuts.
“We tested it all the time and I never had to re-torque in the two years we had them on the trailer,” explained Perrotta. “The only way it will come loose is if the stud breaks, and if that happens, then there’s nothing you could do.”
Even with the device’s ability to lock wheel nuts in place for an extended amount of time, the process has had some growing pains.
“I’m not going to sit here and tell you everything was perfect right from the beginning,” Perrotta told Truck West. “The one problem we had was a corrosion issue and it was hard to get the caps off if you had to change the wheel.”
“The only problem we’ve come across in all the miles and miles and miles, was the corrosion, but that’s why we’re going with plastic,” added Mottershead.
To avoid future problems of corrosion due to the touching of aluminum and steel, the socket will be designed in the future using a heavy-duty polyurethane plastic.
With the final adjustments made and with a road-tested product, the pair of entrepreneurs are looking to team up with a manufacturer to get the product mass produced.
“I could never afford to equip all of my trailers because of the cost of machining, but if these were mass produced I can’t see anyone not buying them,” said Perrotta. “We’ve gone this far with it, now we’re looking to get these on the market. Guys that make the studs are pounding out thousands a day, but to do them individually costs a lot of money. If we were maybe 15 years younger – I’m 60 right now – I’d borrow up to the hilt and do it myself.”