Bike frames are simple on the surface, but can quickly become complicated if you want to fabricate one yourself. Brazing and welding tend to be less common skills than knowing how to bolt things together, so [Arquimaña] has brought us the OpenBike to make the process accessible to more people.
An open-source set of files designed for CNCs and 3D printers, the OpenBike uses readily available materials like sheet plywood to make a sturdy, if unconventional-looking, bicycle. Like many other consumer goods, most bike frames are currently built in Asia. This allows for economies of scale, but removes locals from the design process. By using simpler tools, OpenBike allows for more local direction of what features might be needed for a particular region.
Shifting even a small portion of trips to more active forms of transport is an important part of lowering carbon emissions, so making bikes a more attractive means of transportation is always welcome. What might be important in one region might be superfluous and expensive in another (multiple gears in a hilly region, for example). OpenBike could be especially useful as a way to rapid-prototype different feature sets for a particular region before committing to a more traditional frame-building technique for larger batches of bikes.
If you want to see some other bike hacks, why not check out this extending bicycle, this steampunk recumbent trike, or these bike hacks from around the world?
via Yanko Design
This has a big flaw in my mind: The lack of a horizontal connection between the rear hub and the the bottom bracket makes all the force of braking transfer across a torque arm to the frame. This missing element is normally called a chain stay on a conventional bike frame. This wood frame will work, but a heavy load and a slam of the brakes could cause frame failure over time.
The chain would be taught on the bottom half under braking providing some support 👍
It’s your teeth, not mine.
The main braking force will be on the front wheels anyway, which never has such a provision for reasons of being able to steer.
How much is this bike
I’ve seen properly designed and manufactured aluminum bike frames fail from repeated impacts from uneven road surfaces, I find it hard to believe this would stand up to real-world conditions. Also, while one might expect a two-wheeled vehicle does not experience sideways forces on the frame and wheels, that’s not always valid, when a wheel starts sliding sideways and then regains traction, there can be a significant force, which may end badly if the wood, that would be loaded very unfavorably in that case, would snap.
Some “features”, such as brakes, seem to be completely missing, probably because brakes would exert large forces on the frame. Who needs brakes anyway?
Bicycle frames aren’t very material or labor intensive to produce, and can last almost forever. It’s a novelty, let’s not pretend this is a solution to an actual problem, or a viable or safe vehicle for anyone to use for actual transportation.
Pedal backwards for brakes?
The evolution from wood to aluminum alloy airframes came about not because of any great superiority of aluminum over wood, but because of greater manufacturability on production lines. In fact, there were several successful wooden warplanes in WW2. The fact that aluminum frames fail in extreme applications does not necessarily mean that wood will fail in the same application.
This. Aluminum can fail from fatigue even at relatively low loads if the cycle count gets high enough. Wood on the other hand has a fatigue limit, and can sustain minor repetitive loads indefinitely. This is why springs are never made of aluminum, but can be made of wood (e.g. a longbow) or steel (as in vehicle suspensions).
Well, for aluminum as a spring, you would be looking for something with a high Young modulus which it as an element does not have but there are several other factors as well that generally discourage aluminum as a spring material.
That said, wood cannot sustain getting wet or mold or mildew or swelling or being eaten by bugs or cracking or combusting or loads along certain axes though.
Wood most certainly fails in it’s own set of applications. Not to mention it’s rather heavy, warps and is affected by humidity in several ways plus not terribly strong. Among several other problems for many applications.
At least it’s somewhat cheap by comparison.
You realize the vast majority of problems you posted are solved by varnish or paint, right? People have known how to build things with wood for awhile, you don’t need to worry about it.
There is impregnated plywood – it will resist mold and bugs, and will also resist humidity too.
Just give it layer or two of fiberglass or carbon fiber. They’ll be just fine.
I wouldn’t think it would hold up in real world use and I bet anything if some child would ride one that child would be made fun of from his or her peers.
If the bullies break his bike, they will be surprised by how quickly and easily it is repaired.
Pointless, until he _hurts_ the bully, she will continue. Standing up to a bully is a growth experience for both.
Teachers with their ‘violence never solves anything’ lie are just wrong.
The kid doesn’t have to win the fight, just hurt the SOB so he doesn’t quickly forget.
I don’t know why I have such a bad reaction to these particular YouTubers, must be the shoe covers and shiteating grins. Plywood bike frames are a _terrible_ idea, but those are common as dirt. Hope they test to destruction by personally riding it. I’d click on that video.
What a great bicycle hack! They’re absolutely lovely :-)
Caution that front “seat” is dangerous even with a dead load as it’s mass screws with steering response.
I had a front basket years ago, never again.
You just aren’t Dutch enough.
A front basket is something that a rider can get used to. I’d be more concerned about the lack of a chain guard.
Unless there’s no freewheel clutch in the hub, the chain has about zero energy when coasting. If you are pedaling hard and somehow manage to get a body part between the chain and sprocket, you have achieved a near impossible feat. I’ve only had one bike in my life that HAD a chain guard. About the worst thing that happens is your trouser cuffs get greasy, and a clothespin or binder clip on the outside of the pant leg prevents even that. Maybe a little different if you have an e-bike that is powered from the front sprocket, but that’s not what this is about.
I’ve had my pants chewed by unguarded chains. Getting your leg suddenly stuck on the pedals is a recipe for falling over and breaking an arm instead.
It all depends on the vertical angle of the pivoting point of the steering wheel . I married my wife and drove her to the ceremony on the front shelf of my transporter bike from 1936 and it was very easy as the angle is very flat and the steering wheel wants to stay straight ahead of itself.
Moder bikes use a steeper angle. Very unstable for my taste.
Btw. Its my daily ride.
Of course i’m from the Neterlands…
At first, I was skeptical. I thought it looked like a significant portion of the bike was just pulled from a cheap used bike. e.g head-set, hub, rim, wheels, tire, brake pads/cables/levers, chain, derailleur, crank, cogs, pedals, seat saddle, seat post, grips, etc. I figured they’re basically recommending you buy a used bike and replace the frame and handlebars with something worse. But the more I looked into it, the more I realized that’s exactly what’s happening. The files are nearly identical to plywood bike designs that have been in boys life and pop mech etc for decades, but they require an email and monetize ithem.
Could someone explain the booties in the pic…
“Could someone explain the booties in the pic…”
I’m guessing the photographer didn’t want them messing up his nice “backdrop?”
That was exactly my guess. That’s a pretty big (read: expensive) piece of seamless paper. Probably they didn’t intend to be in the photo at all, but oh, wait: there’s no kickstand!
My kids have a wooden balance bike – made in the UK I believe – so still shipped half way around the world.
It has been a fantastic bike for them them to learn on and now after 3 active boys learning to ride the bike is showing some issues.
The timber tends to compress at the joints so regular tightening of nuts and bolts is a must. Leaving it out in the sun and rain makes it look scrappy rather quickly.
It’s had constant use for the last 6 years and while it has been great I don’t see it lasting through another 6 years ( all the boys have progressed to peddle bikes but they still love gliding around on the balance bike.
Just if anyway is interested I have found the balance bike to have been the lost effective way for the kids to learn to ride. No training wheels needed and all three of them were riding 2 wheeled peddle bikes within a week of their 3rd birthdays
More accessible to who? I learned to build steel frames from a noted British maker of tandems using nothing more than a hacksaw, a couple of files, and a brazing torch. I suspect in many low income parts of the world you’re far more likely to find these than a 3D printer and a CNC router.
This looks like one of those great ideas that come from someone with no actual working knowledge of what’s involved.
I bet with a steady hand one can cut the plywood parts with a jigsaw, too.
Sounds like another case of the engineer-savior trap to me: https://hackaday.com/2017/08/03/avoiding-the-engineer-saviour-trap/
It’s not solving any problem, just money sink for the people with disposable incomes. A complete bicycle is so cheap compared to the cost of that plywood and labor to cut it up.
If you’re hard-up for a bicycle frame, you don’t need a welder, CNC machine, or 3D printer to make one. Take a look at the next kerbside chuck-out, and you’ll find innumerable bike frames, most with all parts attached, just begging for some love. If you don’t like sending even more money east (is Taiwan east?), then it’s about re-using and restoring. Take the Cuban automotive situation as a shining example.
So many bikes are ending up in the landfill nowadays.
In college the police department had annual bike auction. Bikes are free-to-cheap if you want to go that route.
Yeah, I bought my first 10-speed at one for $30, a John Deere, fortunately pre-DRM.
Yes so many bikes at the waste tip with v little wrong with them. All that high energy use steel & aluminium gone to high energy use recycling, when they just need easy repairs.
Birch ply is great & doesn’t involve felling tropical forests. As pointed out, ply kids trainer bikes have been around for decades. It’s an interesting project for design / engineering students. You could build one entirely with hand tools, use headset etc from broken bikes (plenty of bent bikes out there for parts). There are definitely sideways forces on bikes, front forks / headstock / wheel in particular. To some extent those areas can be reinforced & would hold up to gentle riding. Fat tyres for a little suspension would help. 20 stone riders need not apply! As noted it can be finished in grp resin so water damage is less likely. But £150 plus for a sheet of 18mm birch it might be cheaper to buy some steel tube & learn to braze or weld!
Built a few fiberglass frames here. Now looking at polypropylene honeycomb 5mm x 48” x 96” , for fairings and panniers.
Plywood though absorbs water, can warp or rot .
There was an Israeli man who inherited a 55 gallon drum of lacquer, and he made cardboard bicycles until the lacquer was gone.