Gravity bike

This bicycle has no pedals and really nothing that resembles a seat. It’s not so much a way to get around as it’s a way to get down. Down from the mountain, and down low to the pavement. This is a gravity bike built by the guys at S.I.N. Cycles.

The frame is a long triangle which stretches the wheel base to make room for the rider. After getting the layout just right and welding the frame together they added the rather unorthodox building step of pouring molten lead into the hollow frame tube. This bike is used to descend a mountain road with the force of gravity, so the extra weight will help pull it just a bit faster. There’s one thing you’ll want to make sure is working before you climb aboard — the single front brake which you’ll need when coming into the curves. Check out some ride footage on this thing in the video after the break.

Continue reading “Gravity bike”

Teens pulled over while driving their wooden roadster

From this view we would think the handmade wooden roadster (translated) was street legal. But it’s missing a few items that are required to take it out on the highway. The teenagers that built it were pulled over the other night (translated) and cited for driving without a speedometer or side indicator lights.

The image above shows the mark II of their design. Sadly they crashed the first version, which gave them a chance to overhaul the entire design. Now they have a proper frame which was welded from steel square tube. It’s got an impressive rack and pinion steering system and shock absorbing suspension in the front and rear. A dirt bike engine mounted behind the seats drives the rear wheels via a chain. They’ve used an Arduino to add turn signals, and have headlights for night driving.

[Gerrit] sent in the tip on this one and he figures that with an Arduino already being used in the vehicle it should be a quick fix to add a speedometer and get back on the road.

128-inch silver screen for your viewing room

This huge projection screen fills an odd alcove in [Dodge Boy’s] screening room. He built it himself for under $200. The materials, tools, and techniques make this a possibility for anyone who wants their own projection setup.

The frame is made of pine 1×3 dimensional lumber. To keep the fabric from touching the supports in the center of the frame he added quarter-round trim to around the perimeter. From there he painted it black and went for a test-fit. The bad news is that the drywall is neither perfectly flat, nor parallel/square. He ended up taking the trim off and ripping down one side of the frame. That did the trick and he went on to stretch spandex over the whole thing. The frame hangs from a french cleat on either side of the opening. From what we can tell, the surface is just fabric and not painted as we usually see with these setups.

[Dodge Boy’s] utility room shares the back wall of the screening room. That’s where he stores the HTPC which feeds he project, with an RF remote to control it through the wall.

[via Reddit]

CNC milled bicycle frame jig

This bicycle frame jig is cut from MDF. It’s the latest in a growing trend that we love to see: the increasing availability of manufacturing techniques for the common hacker. This is a Kickstarter project, and alas it appears the designs are not available for you to cut your own. But we love the potential this shows, and maybe you can use the concept the next time you’re welding together a frame for something.

We really never look at building traditional frames at home. Mostly it’s the oddities that catch our eye. But if you’re into cycling and want to get your own custom-fit frame this has got to be the lowest-cost option available. In fact, you can get the jig and a tube set for under $600. The frame can be fit with just a few hand tools (a hack saw and a file). It uses lugs so the joints will be strong as long as you get the pipes fitting well enough for a quality welded joint.

Pactuator: Mechanical Pac-Man Frame

As a proof of concept for his long term work in progress “The Pac-Machina” (an electro-mechanical reimagining of a Pac-Man cabinet), [Jonathan] needed some way to make a mechanical Pac-Man, flappy jaw and all. After working through a couple different design possibilities, he decided on an interesting setup which includes using a cog with only half its teeth to make the mouth open and close. Unfortunately, NAMCO BANDAI has asked him nicely not to sell these as kits, but he has helpfully included just about all that is required to make one of these from scratch. [Jonathan] even cut and laser etched his own faux-Victorian frame to keep his proof of concept Pac-Man ready until needed for the main project.

Web-enabled LED pegboard

[Norm Santos] whipped up an LED light board that you can draw on through their web interface. We tried it out but unfortunately the live feed is currently offline. That doesn’t diminish our appreciation for the time-lapse build video after the break. Indeed it was a mountain of hot glueing and a couple of days of soldering. Our only beef is that for every LED on the board there are three empty peg holes. To us this is just begging to be augmented with blue, green, and white LEDs for a more spectacular result. What they have now encompases 350 LEDs managed by five microcontrollers, which took about two days to solder (for five people) and to hammer out some code. Continue reading “Web-enabled LED pegboard”

Server enclosure from 22 rolls of tape

Who needs metal, wood, or acrylic if you are talented with duct tape? This server is housed in a 20-sided enclosure made entirely of duct tape, 22 rolls of it. A team of seven completed the project after eight build session over the course of about ten days. It’s currently in use at this year’s MillionManLan 9 as confirmed by this incredibly boring live feed.

However whimsical, we do appreciate the build process. Tubes are rolled until they reach the specified thickness, then cut to length on a chop saw. More sticky stuff is applied to the joints and piece by piece the frame comes together. From the diagram laying off to the side in one of the pictures it looks like they did the smart thing by designing this in CAD before getting their hands dirty sticky.