100mm Castors Wheel

This article is from the November 2014 issue of Wired magazine. Be the first to read print articles prior to WIRED’s online release and receive tons of additional content with an online subscription.
When his 10-year-old son asked about building a roller coaster in their garden, Will Pemble, a management consultant and founder of the web hosting company web.com, offered to help. Six months later, the result was a 55m course costing around £2,000 which, according to Pemble, was “a little out of hand”. Here’s how to build your own roller coaster.
Stringers 12 x 1.7 m four by two Stands 11 x 3 m four by four, 5 dowels 40 mm x 10 mm, 400 Torx screws with a head of 100 mm, 40 bags of concrete 25 kg each
Plan your route To plan the route of your roller coaster and calculate the height of the poles and the length of the track you want to build, Pemble recommends NoLimits 2 roller coaster simulator.
Bury your poles. Dig a post hole every 1.5 meters along the route. “Each of them should be about one third of the height of the column and 25 centimeters in diameter,” Pemble said. Cut the posts to size – remember one third will be in the ground – then place them in the holes and fill them with concrete.
Prepare guides. Drill two holes at both ends of each cable tie, then use wood screws to attach them to the top of each rack in a T shape.
Drill two holes in each PVC pipe – “make sure they’re buried from the outside,” Pemble says. Then screw them to the end of each tie.
Trace Repeat this to connect every 30 cm along the pipe. Each 5m section of track is then connected to the next section of track by placing 40mm pins inside the ends of the PVC pipe, then holes are drilled and screws are driven in to attach the tie to the connection.
Fixed straight sections For straight sections of track, connect a longer four-by-two stringer between each stanchion running along the center line of the track. Attach the cables with deck screws to prevent the track from bending under the weight of the vehicle as it passes.
Attaching the Casters in Place Screw the casters to the ends of a 610mm four by two wheel with a distance of 420mm between the center lines of each wheel. Screw the other two casters to the center of the two 270mm four-by-two casters.
Screw the wind deflector to the center of the two 190mm 4×2 wheels and attach the end of each roller to the 270mm 4×2 wheel at right angles. The ends should hook onto each tube, with all wheels moving along it. Screw the plywood to the outside and repeat on the back.
To apply for a child car seat for the main car, screw the large car seat onto the wooden platform. To attach the wheel assemblies, place a Susan inert bearing between the top of each assembly and the bottom of the cart platform and use a large bolt to tie them together in the center.
Searching for Crash Test Dummies “When you do a project like this, it’s very, very important to first test it at 200% of normal load,” emphasizes Pemble. “I can’t tell you how many sandbags I killed while testing the roller coaster, but I can tell you that none of the kids got hurt.”