The American Birkebeiner is the second largest cross-country skiing race in the world and is quite a big deal within that sport. At 55 kilometers it’s not a short event, either, requiring a significant amount of training to even complete, let alone perform well enough to be competitive. Around a decade ago, friends [Joe] and [Chris] ran afoul of the rules when [Joe] accidentally won the race wearing [Chris]’s assigned entry number, a technicality that resulted in both being banned from the race for two years. Now they’re back, having learned their lesson, and are strictly adhering to those rules this time using these tandem cross-country skis.
The idea for this build was to make sure they could both compete in the race and win because they’d compete in a category no one enters, mostly because it effectively didn’t exist before these two invented it. This required a custom set of skis, but since ski manufacturers don’t typically make skis for two people, they had to get creative. The duo picked up the longest pair of skis they could find at their local ski shop, moving the bindings forward on the skis to make room for the second set of bindings that were added to the back.
This presented a few unique challenges, the first of which is that cross-country skis typically use a special material on the bottom of the skis which grabs the snow to make uphill travel possible, and with the wider distribution of weight this material wasn’t functioning at peak efficiency. The other problem was the stress on the bindings caused by two riders, especially during a crash. This eventually resulted in a broken binding while [Joe] and [Chris] were training. They then upgraded to a more modern pair of skis rated for a single 269-pound rider, had the bindings fitted for two riders, and added a special grip tape over the larger area on the bottom of the ski.
After four months of training and getting in sync, the two were ready for the race. The results are covered in a second video linked below, and while neither of them won the overall race this time, they did finish the event with in-tact skis, first in the new “tandem” class, and completely within the bounds of the strict rules of the race as well. Although winter is winding down in the northern hemisphere, for any of our southern friends looking for some other things to do with an old set of skis for the upcoming winter season, take a look at this sled which adapts some alpine skis to achieve some extremely high speeds.
Continue reading “Hacking Skis, Rules, And Friendships”
With all the futuristic technology currently at our disposal, it seems a little bizarre that most passenger vehicles are essentially the same thing that they were a century ago. Four wheels, a motor, and some seats would appear to be a difficult formula to beat. But in the 3D printing world where rapid prototyping is the name of the game, some unique vehicle designs have been pushed out especially in the RC world. One of the latest comes to us from [RCLifeOn] in the form of a single-wheeled RC snowmobile.
While not a traditional snowmobile with tracks, this one does share some similarities. It has one drive wheel in the back printed with TPR for flexibility and it also includes studs all along its entire circumference to give it better traction on ice. There are runners in the front made from old ice skates which the vehicle uses for steering, and it’s all tied together with an RC controller and some lithium batteries to handle steering and driving the electric motor.
There were some design flaws in the first iteration of this vehicle, including a very large turning radius, a gearing setup with an unnecessarily high torque, and a frame that was too flexible for the chain drive. [RCLifeOn] was also testing this on a lake which looked like it was just about to revert to a liquid state which made for some interesting video segments of him retrieving the stuck vehicle with a tree branch and string. All in all, we are hopeful for a second revision in the future when some of these issues are hammered out and this one-of-a-kind vehicle can really rip across the frozen wastes not unlike this other interesting snowmobile from a decade ago.
Continue reading “RC Snowmobile Makes Tracks On Ice”
A little face protection is a great idea when first testing out your homemade bow. [Austin Karls] made this recurve bow during what he calls an engineer’s Spring break.
He settled on the idea after seeing a few other projects like it on Reddit. After first drawing up a plan he headed down to the shop to cut out the wooden riser (the middle part of a bow). Unlike traditional recurve bows this is made up of three parts. Traditionally you would laminate different types of wood to achieve the flexibility and tension levels desired. But [Austin] went with a synthetic material: the tips of two skis. Each were cut to the final length and affixed to the riser with a pair of bolts.
After a few test shots he gained confidence in the design and did away with the face mask. Now if you’re in the market to take your existing bow and add some firepower to it you’ll want to look in on this shotgun enhanced compound bow.