Urban Transport

Your next bike could be made from folded sheet metal

Your next bike could be made f...
Ronin Bicycle Works is planning on manufacturing a line of bicycles with frames made from hand-folded sheet metal
Ronin Bicycle Works is planning on manufacturing a line of bicycles with frames made from hand-folded sheet metal
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Ronin's finished frame weighs under three pounds
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Ronin's finished frame weighs under three pounds
Ronin bike-builder Mark, working on one of the prototype's chainstays
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Ronin bike-builder Mark, working on one of the prototype's chainstays
Ronin bike-builder Rob, riding the prototype in San Francisco
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Ronin bike-builder Rob, riding the prototype in San Francisco
The prototype, before being painted
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The prototype, before being painted
Ronin Bicycle Works is planning on manufacturing a line of bicycles with frames made from hand-folded sheet metal
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Ronin Bicycle Works is planning on manufacturing a line of bicycles with frames made from hand-folded sheet metal
It took under three weeks to design and build the prototype
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It took under three weeks to design and build the prototype

Go into any bicycle store, and pretty much all of the bikes in there will have frames made from metal tubes or carbon fiber. A few manufacturers have gotten a bit more adventurous, offering frames made of bamboo or wood, while some have even experimented with things like aramid panels and nylon. A trio of San Francisco-based entrepreneurs, however, have created a prototype bicycle using yet another frame material – hand-folded sheet metal. They claim that their product is lighter, stronger and cheaper to produce than an aluminum-tube frame, and they’re hoping to be able to sell you one.

Rob, Mark and Andy are three mechanical engineers, who make up the company known as Ronin Metal Masters. They have devised a patented system for cutting lines of perforations into laser- or punch-cut pieces of sheet metal, that allows those sheets to be folded by hand. In the folding process, if desired, some sheets can be curved into pre-stressed self-reinforcing tubes. The individual folded sheets are then riveted together, or glued using automotive chassis epoxy. This allows them to be formed into items such as bracket joints for sheds, funky furniture ... and now, a street bicycle.

After some experiments using heavy stock paper, the current prototype was built out of 0.024 inch (0.6 mm)-thick 6061-T6 aluminum. The entire process took less than three weeks, and the frame itself weighs under three pounds (1.4 kg). According to the designers, it delivers a spritely, rigid ride.

The prototype, before being painted
The prototype, before being painted

While the frame certainly has a unique “iron bridge” look to it, the choice of material goes beyond aesthetics. Because no welding is required, there is no risk of weakening the metal where welds are applied – a definite concern when building conventional metal frames. It also means that the frames wouldn’t have to be built in factories with industrial-strength welding equipment. Instead, it is hoped that the perforated sheets could eventually be “printed” at local outlets, then glued and riveted on location. This approach would greatly reduce transportation costs for Ronin (which would presumably be reflected in the price tag), although it would no doubt introduce some logistic complications, such as making sure that all the outlets had the proper machinery and metal stock.

Presently, the three bike-builders plan on offering buyers five options for the type of metal used: regular or high-end steel or aluminum, or a single grade of titanium. Estimated prices range from US$199 for a regular steel frame, to $999 for a titanium model. The first model that they plan on producing, made from high-end aluminum, should be priced around $499 – frame only.

They are currently raising funds on Kickstarter, to finance an initial run of 100 frames. A pledge of $300 will get you an unpainted frame, when and if they reach production, while $1,000 will score you a complete painted bicycle.

More information is available in their pitch video below.

Source: Ronin Bicycle Works

26 comments
Edgar Castelo
Why not stamped sheet metal? They make even firearms that way!
Mr Stiffy
I like that....... Rather than serving up the kids the usual packed crap for Hexmas, it would be good to say, "Heyyyy lets BUILD a bicycle!!!" I am a bit wary of pop rivets, especially on things that are subject to stress reversal, and I am frightened to death of bicycles coming apart underneath me, down hill at great speed..... But as I am a big fellow, if I could be satisfied that this frame would hold together for say 10 years without "loosening up" I'd endorse this. Partly because I like things "you get to do", partly because you can include other people in it, and partly because I like the "Built by people" look, over the factory blandness. I also like it because of all the rivets and "cleverness much", and one of my friends was the late great professor Charles Slack - who with Timothy Leary pushed the LSD in the 60's. And you know the while LSD does have some "unique" poroperties, all the drug users really talked out their rear ends, LSD isn't mind expanding - "LIFE is mind expanding, and life is a wonderful addiction - and there is so many fascination things to do - and this bike just reeks of endless fascination and while the stoners are sitting around on the couch - this bike and things like it - is where life is happening." I can just see myself "Oooo I want to do this too!" and just enjoying making them..... Dammit - it just LOOKS like something that you just HAVE TOO tinker with.... and polish and.....
Matt Rings
Give it a tarnished copper color paint job, and voila! Steampunk Bicycle. Nice look.
Michael Crumpton
Not sure what the point is here. The frames are expensive and need lots of hand work and have holes in them to allow water and other stuff inside the frame. I Love folded stuff, but this just looks like a solution for the problem of how to separate hipsters from their cash.
Josie Herbert
Cool concept, but isn't this what Orange has been doing with the Orange 5 frame for a number of years? As demonstrated by Guy Martin in this video http://www.youtube.com/watch?v=mlIYEdRFQu4 filmed at the Orange factory. Guy shows how a flat metal sheet is formed into the downtube of the bike, using a folding machine.
jonoxn
Josies got it right; but pressed or hydroformed sheet-metal frames still require a weld to join the two shells together. However I fail to see how a piece of perforated, folded sheet-metal could have any strength advantage over a "weakened" welded frame. Good welds should only reinforce the strength of the structure it is holding together. But if I see this as a giant jigsaw puzzle with novelty as its core marketing tactic then I think it is pretty cool.
mommus
looks cool, and it could lead to all sorts of interesting styling too.
Mirmillion
Why not just print the frame on your industrial 3-D printer (material notwithstanding)? In any event, I'd like to see a latticework frame and adjustable on-the-fly crank length.
The Hoff
Someone said it is very expensive but for it's weight it is fairly priced. I like it because it looks heavy but it is very light.
William Volk
I saw a recumbent bike built like this in the 1990's at an event in Long Beach. It worked.