Four groups of North Surry students showed off their team creations this week in a prep version of ABC’s Shark Tank.
Members of the Project Lead The Way engineering and design class presented their projects to parents, teachers and friends in the school cafeteria Thursday night.
On the reality show Shark Tank, budding entrepreneurs give presentations to a panel of “sharks” that include Dallas Mavericks owner Mark Cuban.
At North Surry, the four teams showed sketches, renderings, photos, charts, logos and prototypes for their creations. After a short presentation (10-12 minutes long), the audience was encouraged to ask questions and grade teams on their work.
This feedback is essential in helping students fine-tune their work, both now and in their future endeavors, noted teacher Jonathan Sutphin, PLTW leader.
The four groups include five students who plan to pursue engineering in college and some who will take their engineering skills into the military, Sutphin told the crowd.
Hydro Absorbent Sole
Noah Sadler and twins Jeremiah and Isaiah Griffin investigated ways to keep feet dry in wet conditions.
Many shoes aren’t water-resistant, and athletic footwear is especially problematic because of its built-in venting.
Waterproofing spray doesn’t work on some shoes and doesn’t last very long, said Sadler.
After looking at some existing designs in footwear, the team chose to create a waterproof lining using the nylon fabric like that found in a rain slicker.
Sadler said they cut the upper half of a shoe off the sole and then applied the nylon. However, putting the shoe back together was problematic.
The team went to a Winston-Salem shoe-repair company to see what could be done, but the repairman said too much damage had been done, Sadler told the group.
The next attempt was a liner that could be inserted into the shoe and glued into place.
The product needed to be effective and durable, but also affordable to make so it could be affordable to purchase if it ever reached the marketplace, explained Jeremiah Griffin.
Loctite fabric adhesive held the nylon inside the shoe, said Isaiah Griffin. Then to keep water from splashing up and running down into the shoe, the team created an elastic top to the liner to go just above the ankle.
In the meantime, Jeremiah said they designed a logo with the three initials of the title, H.A.S., were stacked together, with the curve and splash of a wave encircling the letters.
The logo was sewn into the tongue of the shoe, said Isaiah.
Once the prototype was assembled, Isaiah said he submerged his foot in a bucket of water, and the waterproofing failed. But from that failure, the team figured out what to do next.
The next attempt worked fine.
And with a store-bought Dr. Scholl’s liner, the shoe was comfortable to wear all day and even when jogging at track practice, said Isaiah.
Up next were Barrett Slate, Tyler Cook and John Smith.
Slate and Smith were starters on the Greyhounds tennis team, and they pursued a question related to their sport.
A tennis ball doesn’t have a long life in a tournament, Smith said. Balls come out of their container strong and bouncy, but in as little as seven games, the balls have lost some bounce.
That’s not even long enough to play one full match, he noted.
Their project looked for a way to create a tennis ball that could last twice as long and survive one match.
At last year’s U.S. Open, an estimated 70,000 tennis balls were used throughout the week, said Smith. Now imagine the other three majors, plus the regular weekly tournament. Then there are tens of thousands of college and high school teams.
At a department store, a three-pack of ball is $2, so enough balls to supply the U.S. Open alone would cost about $47,000 at retail, Smith pointed out.
If a company could develop a ball that lasted longer, the field is wide open, he said.
What they discovered is that tennis balls lose some of their air during use. Two halves of the ball are attached together, but a tiny drop in air pressure can lead to less bounce.
A regulation tennis ball is tested by dropping it from 100 inches and seeing that it bounces back up to 53-57 inches, said Smith.
A basketball loses air, but it can be pumped back up. Cook said the team looked at opening the ball up and inserting an air valve like a basketball would use. However, tennis balls flex a great deal on impact, and they couldn’t keep the valve airtight.
Next the team tried removing the felt from a ball and coating the surface with a flexible sealant called Leak Stopper Rubber Flexx.
That did the job of holding air in longer, and retained almost all the required bounciness.
Then came applying the felt.
The first adhesive was a Loctite product from a caulking gun, but that product hurt the performance, said Cook.
Gorilla Glue was really bad, said Cook.
Smith said he was holding the felt onto the ball with his bare hands, and the glue soaked through and attached the felt to his palms.
The best result came from a Loctite spray adhesive.
While the ball bounced well, however, the spray adhesive wasn’t strong enough to stand up to the rigors of a tennis match, said Slate. The prototype’s cover was pulling free by the end of the testing phase.
If the project were to continue, the next step would be creating a thinner coat of flexible seal to improve the bounce, then an industrial-strength adhesive such as what companies already are using would need to be applied to the felt, said Slate.
In his spare time, North’s Trey Stamper is a dirt-track racer who has found the winner’s circle at Friendship Speedway in Elkin.
In order to keep his car going, Stamper spends a lot of time in the garage.
A common complain from mechanics is when a tool or small part slips from their hands and fall in or under the engine.
Auto parts stores sell magnetic wands to extend under the car to reach fallen nuts, bolts and screws, but Stamper in his team (J.D. Sawyers, William Tate and Eli Combs) wanted a work glove that could hold onto metal.
Sawyers said that a big magnet in the palm could help with holding tools, but tests showed it didn’t help reliably with small metal pieces like nuts out at the fingertips.
The team considered some sort of thimble-like magnet in the ends of the gloves, said Tate, but rejected the idea because touch sensitivity is needed in the tips.
There are many kinds of work gloves available in stores, but some materials were unsuitable for a hot glue gun, said Sawyers.
The heat melted a big hole in one glove tried, said Tate. Synthetic leather and leather had the heat resistance and the durability necessary.
Nylon thread was the strongest of their samples for sewing in the magnets, said Combs.
When trying the gloves, the presence of the magnets was noticeable at first, but after a few minutes, Combs said he’d forgotten all about them.
Someone with more experience with sewing could do a tighter, better job with the seams, Combs admitted, but that’s something that could be improved in future prototypes.
Tate said the team surveyed their fellow students and the faculty to see if this was a product they would be interested in. Positive feedback showed a possible marketplace for such a product.
Tailgating is an American tradition, but not all vehicles come equipped with a tailgate – a problem the final group looked to remedy.
Small off-road vehicles like the Jeep Wrangler don’t have space to pack a folding table to take to the ball game or a country picnic.
Abby Andrews, Andrew Cave, Grace Swift and Jacob Shelton looked at ways to satisfy this need.
A solution was to attach a table to the Jeep itself.
Cave said they considered ways to mount a table surface to the outside of the space tire bolted onto the rear of the Wrangler.
A hinge on the bottom and levers/straps on the outside could allow the table to fold down from the tire to create a tabletop, Cave said.
The team looked at creating a round, plastic tabletop, but they didn’t have any way to manufacture their own tops, and searching through local stores didn’t reveal any ready answers.
Instead, they chose to work with a local company to create a metal tabletop.
The metal surface held up well in testing, said Swift, but the hinge used was a little weak. And it did show some signs of rust after being exposed to the elements for days. A stronger hinge with rust-resistant properties would be a better choice in the next attempt.
The side supports did their job. Cave said they used nylon straps from a ratcheting tie-down strap system; the nylon had a test strength of 400 pounds.
But they might have reconsidered how the straps attached to the tabletop if given more time, said Andrews. And because the table is metal and sturdy, the weight makes the top a little cumbersome. She suggested adding a handle near the top to aid with folding out and repacking the top.
While the initial testing was with a Jeep in mind, a product could be adapted to fit other vehicles with spare tires on the back like some models of the Honda CR-V and Toyota Land Cruiser and others.
Reach Jeff at 415-4692.