Israeli inventor has backers for cardboard bicycle

Oct 17, 2012 by Nancy Owano report

(Phys.org)—Don't tell Izhar Gafni that a bicycle can't be made of cardboard. An Israeli engineer working in industrial design, he was always fascinated by the potential that comes from the interplay of technologies applied to materials. Gafni was too curious about turning materials into new uses and he could not take no for an answer. What's more, bicycles, he said, went beyond "hobby." With him, it was "in my soul." That might explain his three years of efforts in coming up with a fully functioning bicycle made of cardboard, which has been accorded ample research and development to reach final stages and readiness to show the world.

Gafni says it all started the day he went to a bicycle shop to purchase parts and he overheard a customer talking about his building a canoe made of cardboard. "The idea stuck in my mind," he said. "Why not build a bicycle made out of cardboard."

This video is not supported by your browser at this time.

He consulted several engineers. They told him it was impossible. For an , "impossible" is often a green light. "At the time, I just knew cardboard was a material for making packages but I explored it further," he said.

Basically, he said, his method was like that in Japanese origami, as he demonstrated how cardboard can be cut and folded for strength. He said his very first prototype looked like something between a box and a . He knew he had real work ahead. Gafni worked for several years in his tool shed to make a suitable model. He studied how he was going to structure the frame, seat and other parts, prototyping and tweaking, planning, sketching, running plans through . He did not use any metal parts. Once the desired shape was formed and cut, he treated the device with what is generally described as "organic materials." The treatment he used made the cycle waterproof and fireproof. He coated the with lacquer paint. The tires were made from recycled rubber.

The estimated cost to make such bicycles would be between nine and twelve dollars. The obvious benefit would be usefulness as an affordable means of transport. Not only is the design now in its final prototype stage but plans are under way for production.

Gafni has secured backing for his project by partnering with ERB, which is managing business and financial aspects of the project.

ERB said that it is raising funds to reach the point where they can have a detailed manufacturing plan under way for the first two platforms, a commercial, urban bike and a kids/youth bike. According to ERB, "These models will be made of almost 100 percent recycled materials and will have the option of adding an electric motor. At this stage we have only the prototype for the commercial bikes as shown on the video."

Explore further: Japan firm showcases 'touchable' 3D technology

More information: www.erb.co.il/en/

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User comments : 52

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alfie_null
4.2 / 5 (5) Oct 17, 2012
Obfuscate slightly and sell for thousands (e.g. "cellulose frame").
tekram
4 / 5 (5) Oct 17, 2012
One really has to question the validity of the cost estimate:
"The estimated cost to make such bicycles would be between nine and twelve dollars."

Just the metal parts on this bicycle could cost $12.
antialias_physorg
3.7 / 5 (3) Oct 17, 2012
when the bicycle would be exposed to humidity for prolonged time, which would limit its strength.

At 9 dollars a pop - who cares? It would almost be a throwaway article (and in countries where it would not be prolonged humidity is motsly a non-issue.)

And as you can see quite plainly in the video: The surface can be impreganted with a resin that makes it weather proof.
cantdrive85
2.7 / 5 (17) Oct 17, 2012
First, it's cheap plastic crap from China, now it's cheap cardboard crap from Israel. I doubt we'll be seeing these bikes at the next X-Games comp.
antialias_physorg
4.7 / 5 (15) Oct 17, 2012
But you will be seeing this 'crap' in some village in Africa (and probably not the 10000 dollar crap you see at the X-games which wouldn't last a month down there for lack of specialized tools and parts for maintenance)

This is a bike that can actually make some people's lives better. Not some toy for rich kids with nothing better to do but bike off walls.
kochevnik
3.5 / 5 (11) Oct 17, 2012
$20 materials. $20,000 in labor. Nice art project.
PhotonX
4 / 5 (4) Oct 17, 2012
Mass urban transport. These are something that a city could buy in the tens of thousands, to distribute within the urban core. Ride one across town and leave it for the next rider, and pick up another one for the ride home. Will people steal them? Sure, but who cares at that price. Once that local 'demand' is saturated, there will be bikes everywhere.
.
I should add that the cost cited in the article doesn't sound realistic, though. Also, it doesn't appear to have gearing. Okay for flat terrain like the Netherlands, lousy for a hilly place.
TheGhostofOtto1923
2.4 / 5 (39) Oct 17, 2012
This is a bike that can actually make some people's lives better.
-Until they hit a curb, or let someone who weighed over 120lbs ride it, or until stress cracks caused the thing to fall apart under them.

I bought a cheap sears bike once that developed spiral cracks in the crank after climbing a few hills standing up. So then I bought a cannondale and felt SAFE.

It is funny how so many people fail to appreciate the VALUE of engineers.
At 9 dollars a pop - who cares? It would almost be a throwaway article
Right. For throwaway people.
Estevan57
2.6 / 5 (39) Oct 17, 2012
According to the inventor (AN ENGINEER) it will support up to 485 pounds. Even your fat ass, Otto.

http://www.fastco...o-485lbs

"In testing the durability of the treated cardboard, Gafni said he immersed a cross-section in a water tank for several months and it retained all its hardened characteristics."

From this article.
http://news.yahoo...689.html

This would be just the thing for a city or town looking to start a bicycle sharing or rental system. The low price would overcome the two most common hurdles - maintenance and theft.
TheGhostofOtto1923
2.7 / 5 (29) Oct 18, 2012
Hello scummy troll,

Well if I was wrong I would promptly admit it, but since Im not, I wont. Radical designs such as these require much stress- and field-testing before they are sold to the general public. Theres no indication that this 'engineer' of whatever sort he might be, has done this.

Go to a bike shop and look at how bikes are constructed. Or simply take a look at your own sitz bath very closely. You will see that great pains are taken to reinforce joints and attachment points.

I bet that if this cardboard wonder is ever marketed it will weigh at least 10 more lbs and cost many times as much because it will be full of carbon fiber and composites. Or it will be made in china where entrepreneurs dont care much about lawsuits and criminal negligence.
TopherTO
3.8 / 5 (4) Oct 18, 2012
I bought a cheap sears bike once that developed spiral cracks in the crank after climbing a few hills standing up. So then I bought a cannondale and felt SAFE.


Yes well most people cannot, or chose not, spend $1500/$2000 on a Cannondale bike. Moreover, you spent all that money on a top end brand to "feel safe" as you said. Just like people buy $100,000 cars to feel luxurious or $500 sun glasses to feel fashionable.

But affordable means or transportation like this could transform someone's life. Your feelings are just the byproduct of a company's marketing department who sell feelings.
TheGhostofOtto1923
2.7 / 5 (28) Oct 18, 2012
Try this one. I am sure it wont break.
http://www.rei.co...ike-2013

-The sears cost me $325. Also bling glasses wont get you killed unless you get mugged for them.
Estevan57
2.7 / 5 (36) Oct 18, 2012
Well, Otto I didn't actually say you were wrong. I just pointed out that the inventor (an actualy real life engineer!) has tested this device for months (years actually) and his tested limit of 485 pounds is very slightly different than yours, of 120. Read, stupid.

The article DOES mention that the bike has been stress tested through computer simulations. Perhaps not enough to suit you, my porcine pal, but enough testing has been done to secure the investment of thousands of dollars. Bicycle software is easy to use. So is Solidworks.

The basic design IS strong, for a bike. A parallagram frame, with a reinforcement bar to triangulate the front section, and the wheels have only a little rake forward and backward. The riders weight is to the rear, etc.

The bike has never been touted as a hill climber anyway. At twice the weight and cost, it still fulfills its purpose. I wouldn't buy one though, I have a Cannondale.
TheGhostofOtto1923
2.6 / 5 (28) Oct 19, 2012
Sorry I couldn't find parallagram in the dictionary. I do not see anything parallel on this bike at all, even before you sit on it.
The basic design IS strong, for a bike.
No it is strong for a lawn chair. It is obviously weak for something expected to carry a person through traffic, over potholes, and through screeching emergency stops.

But you or your idiot gf are welcome to try it. Maybe you could talk your poor little niece into trying it? For a whole dollar?
I have a Cannondale
I did not know cannondale made walkers. Must be pretty snazzy. Shimano brakes?
Estevan57
2.4 / 5 (34) Oct 19, 2012
Try parallelogram, dumbass. By the way it's Sears not sears. Cannondale, not cannondale.

Look at the frame, stupid. That's Otto, dense by design.
The top member is parallel to the bottom.
The back is parallel to the front.

Ok, so whats obviously weak? Beside you?
Osiris1
3.7 / 5 (3) Oct 19, 2012
As an engineer, I see where the effort has been put to make the thing stronger. However, I might notice that the axle bolts are small. The entire weight is carried on these tow axle bolts. The major weight is carried in the rear as can be seen by the thick structural members below the seat. The chord gusset rear of the triple clamp in the front resist torsion forces normal to the axis of the triple clamped steering shaft axis. Back to the axle bolts, the load is imposed entirely on the projected cross sectional area represented by the bolt diameter times the loaded length of the bolt. This has to be resisted by the strength of the material. More specifically the tendency to be split by the bolt acting as a wedge, splitting the material upward along the centerline of the loaded member as a splitting wedge would split a log. Such would be exacerbated according to the integration of the formula dF=M(summation[da d2a d3a...dna] the impact compensated force eq as taylor series.
Osiris1
3.7 / 5 (3) Oct 19, 2012
Of course again in the real world we have the issue of everpresent eccentric columnar loading represented by the cyclist...pedaling!....an alternating series of semi-random variable eccentric loads through the axle support members as directly or indirectly transmitted through the statically indeterminate frame of the much debated 'parallelogram'..actually part of a modified frame truss when the front fork load is considered. Never the less, how they get there, the axle bolts DO together receive in sum the entire load of the rider and frame thence to the wheel instantaneously directly under the axle bolt to the resistance from the traveled surface as directly opposed resistance vectors acting vertically from the ground. These eccentric loads will impose greater loads at the ends of the axles, and if failure occurs,then there is where they could start unzipping the fork material directly above the axle bolts. First the ends of the axle guide holes will deform in a horiz hourglass shape
Osiris1
3.7 / 5 (3) Oct 19, 2012
The deformation will allow the wheel to wobble, with increasing force arm to smaller retained diameter of the now increasingly and progressively deformed axle guide holes. Like ponding on a roof eventually the fork material, front or rear, fails in a crack, and the bicycle falls as a rude jacknife shape with one or the other, probably the front wheel after a hard bump..folds sideways under the layed down failed fork side member. Such failure may rupture both upper and lower chords of the axle retaining hole, or just one of them. So much for failure mechanism, that leaves the issue of the absolute section modulus of the material, the cardboard. And its known issue of compressibility....plastic deformational compressibility! Absent a little 'cheating' soaking the cardboard in epoxy resin or coating with fiberglass resin roving, this should be straightforward. All the support members are rectangular sections so moments of inertae and bending moments 4 slope deflec analyses simple.
Osiris1
3.7 / 5 (3) Oct 19, 2012
I might add that a working functional knowledge of multivariable vector calculus and and multivariable vector differential equations of several degrees will be necessary to carry through either the virtual work method of extracting the solutions to the statically indeterminate frame, or the simpler more intuitive slope deflection methods of advanced structural analyses. Such could also easily lead to higher level matrix problems....with each term being multiple integrals or diff. equations. I do not think this system will be productive of the more difficult partial differential analyses. That is why our engineer used computers which are happy to cluck along in Linux to get a solution. All really depends on the modulus of elasticity of a compressible material, cardboard. However much this can be strengthened by some process no one has dared to ask about...and that engineeer probably will not tell! A patent may be involved.
TheGhostofOtto1923
3.1 / 5 (21) Oct 19, 2012
By the way it's Sears not sears. Cannondale, not
Yeahyeah I know and it's God not god.
Try parallelogram, dumbass
okay

"Noun
A four-sided plane rectilinear figure with opposite sides parallel."
The top member is parallel to the bottom.
No it's not.
The back is parallel to the front.
No it's not. Idjit. But I understand visual distortion is common with REALLY thick glasses.
Ok, so whats obviously weak? Beside you?
-See the comments from the engineer above.
progressively deformed axle guide holes. Like ponding on a roof eventually the fork material, front or rear, fails in a crack
Yeah I would think fatigue failure would require 'cheating' with more resistant materials at many points, exacerbated by lack of rigidity. And I doubt cardboard seats or handlebars would survive for very long at all.

Nice analysis. You a coffee drinker?
baudrunner
2.7 / 5 (7) Oct 19, 2012
That's right Izhar. Skip right over the wooden bike and shoot straight for the Yugobike.

Hey, balsa bridges strong enough for a truck? So why not balsa bikes? Stronger than paper, I'll bet, and lighter too.
packrat
3.3 / 5 (8) Oct 19, 2012
If this thing sells for less than $50 he is going to sell a whole lot of them to tourist type places because it will be very easy to have them labeled or monogrammed. The design is strong enough to last long enough for them to make money renting them out. ProtonX is right. Cities and places wanting to start ride-share programs will jump all over them.
TheGhostofOtto1923
3.1 / 5 (23) Oct 20, 2012
If this thing sells for less than $50 he is going to sell a whole lot of them to tourist type places because it will be very easy to have them labeled or monogrammed. The design is strong enough to last long enough for them to make money renting them out. ProtonX is right. Cities and places wanting to start ride-share programs will jump all over them.
No because people will be killed and maimed on them and businesses would be sued a lot.
Mike_Massen
3.3 / 5 (7) Oct 20, 2012
Lets be a bit more positive for some of you arrogant knowitalls !

The cardboard is effectively a composite and very likely tougher than it looks, the important issues brought up by Osiris1 are manageable with the appropriate attention.

I wouldn't be surprised to see this design and relevant tweaks successful and for a very reasonable end user price and may well attract subsidies for 3rd world where many are in dire need of cheap transport for water, food and medicines. ie. As a kit for end user assembly.

An innovative advance for sure and potentially a means to recycle some materials and indirectly a means to educate and improve companies long term outlook to shift some semblance of their packing materials to match some structural components for this type of end product and associated similar needs such as chairs, beds etc where feasible :-)

Lets just hope its not sent to the much colder climbs where heating wood is in short supply...
ValeriaT
1 / 5 (3) Oct 20, 2012
$20 materials. $20,000 in labor. Nice art project.
Well, it could be said about every prototype. But the iron is recyclable quite easily (probably better than the cardboard soaked with glue and varnish) and I even don't see an impressive contribution to life environment at the case of cardboard bicycle. It still contains many metallic parts, so it cannot be simply burned - its disposal may be actually more difficult and life-environment demanding, than at the case of classical bicycles.
TheGhostofOtto1923
3 / 5 (24) Oct 20, 2012
The cardboard is effectively a composite and very likely tougher than it looks, the important issues brought up by Osiris1 are manageable with the appropriate attention.
No it's not. There are materials much better suited. Even a composite paper product made for the purpose would make more sense.

Why not make it out of pasta? You could weave it like carbon fiber and be all ecological to boot. It would be big in Verona.
Mike_Massen
3.3 / 5 (7) Oct 20, 2012
TheGhostofOtto1923 doesn't understand English
No it's not. There are materials much better suited...
Of course there are other 'possible' options but, it doesn't change the fact that the 'cardboard' bike is a composite of cardboard and resin so in general and rather appropriate terms it IS a 'composite'. ie. A composition of two or more parts - don't you understand English ?

Husky
4.5 / 5 (4) Oct 20, 2012
i would like to see you guys decide this battle in a cardboard bike race, should be fun to watch
TransmissionDump
2.6 / 5 (5) Oct 21, 2012
"Why not make it out of pasta?"

Because hungry people will steal your bike and eat it.
TheGhostofOtto1923
3.2 / 5 (20) Oct 21, 2012
Of course there are other 'possible' options but, it doesn't change the fact that the 'cardboard' bike is a composite of cardboard and resin so in general and rather appropriate terms it IS a 'composite'. ie. A composition of two or more parts - don't you understand English ?
Well if you read what I wrote again you will see that this is exactly what I said. The english word 'another' is implied. And you forgot to mention the surface coating which is a functional component of the composite.

But a cardboard composite with properties specifically designed for the continuous flexing and point-loading and moisture found in a bicycle might be more appropriate, dont you think? An advantage of composites is they can be better tailored to suit specific applications. An off-the-shelf material is rarely optimal. Quality control becomes critical on such a small structure for instance. A defect acceptable in a box would be disastrous in a chainstay.
Sonhouse
5 / 5 (3) Oct 21, 2012
Well I think the answer to reliability will be seen if and when this bike is mass produced. All the engineering problems listed above may amount to nothing when it hits the road by the thousands, that will be the true test.
Mike_Massen
4 / 5 (8) Oct 21, 2012
TheGhostofOtto1923 makes odd stuff ups
Well if you read what I wrote again you will see that this is exactly what I said.
NO, you said its not a composite and I said it is, can you make up your mind please ?

Does the quote of yours remind perhaps TheGhostofOtto1923 ?
No it's not.
Please stop trying to change history, the evidence is there for all to see, either you dont understand English or cant quite get a handle on writing sentences... Since you 'mis-spoke' it makes sense to apologise...

TheGhostofOtto1923
3.1 / 5 (21) Oct 21, 2012
Mikey dear,

Let's try again. Otto says

"No it's not. There are materials much better suited [than cardboard]. Even a[nother] composite paper product [which is actually] made [or more specifically, engineered] for the purpose would make more sense."

-This is the long version for dweebs and Ausländern. But they are equivalent. Mike[y]. No apologies necessary. But you could be polite and apologize anyway.
TheGhostofOtto1923
3.2 / 5 (20) Oct 21, 2012
There are all sorts of things made starting with paper
http://atlas.medi...s4/4807/

-But it is usually best to select materials specifically designed to accommodate the conditions you are trying to satisfy, or to design these materials from scratch. Especially where the application has such a critical weight-to-performance ratio as a bicycle.
antonima
5 / 5 (2) Oct 21, 2012
This reminds me of a mythbusters episode which was going to test a boat made of frozen newspaper. Apparently the stuff is REALLY strong! like 500 lbs on a little two by four of frozen paper, and thats with the sheets parallel to the ground. I'm sure the cardboard could be dipped in some cheap-ass glue to make it 2,3 times stronger.

10$ for a bicycle would be perfect for tourists. They could just sell them at supermarkets, why bother renting? As a cyclist I know the pain of being unable to bike when I travel. Foldable, lightweight bikes cost 2,3 thousand dollars and then extra for luggage. Not to mention the fear of getting it stolen in some exotic locale. If they can really make a reliable bike (even for a month or two) for 10$, there has got to be a market for that.
Estevan57
2.3 / 5 (31) Oct 21, 2012
What if the conditions you are trying to satisfy are cheap materials, lowest cost possible, and easily mass produced?

In this interview the inventor says he will sell it for approx.
$60 U.S.
http://www.greenp...-photos/
Looks like he's using Solidworks for modeling and perhaps stress calculation.

At $60 it comes close to the cheap bikes available from Walmart and other discounters. For an unknown (for this application) material it might not be the best bike for the buck. Time will tell.
TheGhostofOtto1923
2.8 / 5 (24) Oct 21, 2012
Speaking of dweebs
What if the conditions you are trying to satisfy are cheap materials, lowest cost possible, and easily mass produced?
-You keep forgetting the most important one - safety. Melamine baby food was cheap and easily mass produced in china. Hey - they make furniture out of melamine... Maybe the Chinese could outsell a paper bike with a melamine one - !?!??
Because hungry people will steal your bike and eat it.
-Another advantage in third world countries. Just so there's no melamine in it.
Estevan57
2.3 / 5 (30) Oct 21, 2012
Take your meds, Otto, noone said anything about Melamine but you.
200 pound bike - doh.
Made in Israel, Mr. stupid.
Estevan57
2.4 / 5 (29) Oct 21, 2012
Note to Otto - dude, don't eat the bike.
TheGhostofOtto1923
3.1 / 5 (21) Oct 22, 2012
Hey dweebish troll
Take your meds, Otto, noone said anything about Melamine but you.
No, see, I was giving an EXAMPLE of a comparable instance where unscrupulous people chose to use something cheaper but less safe. This is comparable to you being so compelled to say something - anything - that it matters little to you whether it makes you look like moron or not.

Most would consider this sort if compulsion unsafe, at least for their self-respect. It's sort of like you paying little girls to gangrate people who make you look like a moron, and not caring that this practice makes you look like a moron. At least.

Oh hey I just used another EXAMPLE. Maybe you and your gf pussytard both share a jug of port before you get on the internet? That would explain much-
TheGhostofOtto1923
3.2 / 5 (20) Oct 22, 2012
200 pound bike - doh.
Made in Israel, Mr. stupid.
?? Nobody said anything about 200# bikes. People shouldn't post here when drunk or stoned.
Mike_Massen
3.3 / 5 (7) Oct 22, 2012
TheGhostofOtto1923 admitted
Let's try again. Otto says
Thats your problem, you need to get it right the first time, that way you might save time and argument and have some sense of linguistic precision.

Here is my proposition again so you can clearly understand you need tutelage in grammar and interpretation when I said
The cardboard is effectively a composite and very likely tougher than it looks, the important issues brought up by Osiris1 are manageable with the appropriate attention.
So whey you retorted with "No its not." Which of the following three propositions from my sentence were you denying:-

- its a composite
- likely tougher than it looks
- issues brought up by Osiris1 are manageable

Which of those 3 items did you refer to when you retorted "No its not." ?
Mike_Massen
3.9 / 5 (7) Oct 22, 2012
Yep TheGhostofOtto1923 does need to upgrade his meds when he totally misrepresents issues such as
Melamine baby food was cheap and easily mass produced in china. Hey - they make furniture out of melamine... Maybe the Chinese could outsell a paper bike with a melamine one - !?!??
There is no such thing as "Melamine baby food". Baby food was contaminated by melamine as a means to fake conformance of the protein test only. Some batches of milk also had melamine added for the same reason.

TheGhostofOtto1923 would save a lot of time, effort and noise by not misrepresenting issues.
TheGhostofOtto1923
3.2 / 5 (22) Oct 22, 2012
Thats your problem, you need to get it right the first time, that way you might save time and argument and have some sense of linguistic precision.
-But it still wouldn't deter trolls like yourself now would it? Unless you really are too dense to understand that 'melamine baby food' really does mean 'melamine-tainted baby food' -? Like orange soda really means orange-flavored soda?

Let me try again [for you because you are either trolling or you really are pretty fucking dense]. 'Orange soda' means 'a carbonated beverage containing among other ingredients an artificial flavoring which is recognized by most people as resembling the taste of oranges'. How's that? Anybody ever explain to you what vegemite really is? Troll.
Mike_Massen
4.1 / 5 (9) Oct 22, 2012
TheGhostofOtto1923 is missing so much with a knee Jerk
-But it still wouldn't deter trolls like yourself now would it? Unless you really are too dense to understand that 'melamine baby food' really does mean 'melamine-tainted baby food' -? Like orange soda really means orange-flavored soda?
What a DUMB thing to say, orange flavour is intended by the food designer/manufacturer as a marketable aspect, Melamine poison is NOT by any means comparable, U Nut.

To suggest its comparable is IDIOCY & scientific negligence !

You are missing the fact many who know little of details of chemicals, foods, science etc & are reading these posts, your vagaries are testament to your laziness gets impressed in peoples minds not the essential details that avoid more stuffups.

Its people like you who's linguistic casualness & lack of precision spreads misinformation & dangerous misunderstanding of what should be very really simple issues for others.

Please LIFT your game, you should know better !
TheGhostofOtto1923
3.1 / 5 (21) Oct 22, 2012
Please LIFT your game, you should know better !
OK let's back up here a bit:
The cardboard is effectively a composite
No, it IS a composite as I said.
and very likely tougher than it looks
Well how 'tough' does it 'look'? I see no cardboard in the picture. And what do you think you mean by 'tough'? Osiris addressed functionality in his posts.
the important issues brought up by Osiris1 are manageable with the appropriate attention.
And how could you possibly know this? You're obviously have no structural or material engineering training. 'Tough' is not an engineering term, it is a meat tenderizing term.

You should endeavor to lift your game by not pretending to know things you do not. People as ignorant as you might read your stuff and think they know enough to post inanities too, thereby adding to the clutter. I think this should be actively discouraged don't you? Mike?
obama_socks
1.6 / 5 (13) Oct 24, 2012
Please LIFT your game, you should know better !
OK let's back up here a bit:
The cardboard is effectively a composite
No, it IS a composite as I said.
-Blotto

Mike_Massen is correct. TheGhostofOtto1923 is a liar. Blotto did NOT say that the cardboard is a composite in his reply.

At the bottom of page 1, Mike_Massen says: "The cardboard is effectively a composite and very likely tougher than it looks, the important issues brought up by Osiris1 are manageable with the appropriate attention"….to which Blotto replies, "No it's not. There are materials much better suited. Even a composite paper product made for the purpose would make more sense."

The crucial part of Mike's post is ""The cardboard is effectively a composite and very likely tougher than it looks...." We establish that the cardboard IS a composite AND tougher than it looks, otherwise it could not be used as a bicycle.
[contd]
obama_socks
1.9 / 5 (13) Oct 24, 2012
When Blotto said, "no it's not", he evidently was referring to the second part of Mike's sentence, that the composite is "very likely tougher than it looks", but not denying that it's a composite. Of course, Blotto is too lazy, as usual, to explain clearly what he meant.

While Blotto is known to be a liar who misinterprets and misquotes the posts of others and twists their words to suit himself to try to make them look bad and unknowledgeable, unfortunately, this time he did say on the first page that the cardboard is full of carbon fibers and composites. However, Blotto failed to explain this in his reply to Mike_Massen, thereby once again wasting time and space and argument and missing out on a sense of linguistic precision...as was said.

Blotto is the only "dweeb" in this website but doesn't recognize that fact. Someday, he might have a rude awakening. :P

antialias_physorg
not rated yet Oct 24, 2012
It still contains many metallic parts, so it cannot be simply burned

Standard procedure in thermo-powerplants (those that burn garbage) is to shred the incoming garbage and extract any metal using a magnet. This is very low tech. This kind of bike would be exceedingly easy to recycle (much easier than one made up of other materials)

But it is usually best to select materials specifically designed to accommodate the conditions you are trying to satisfy

In this case the conditions are: extremely low cost and ease of manufacture in a low tech environment while having adequate performance.

I'd say the design fulfills these admirably.
Sonhouse
not rated yet Oct 24, 2012
Magnets work fine for ferrous metals but not so hot for copper or aluminum. It looks like the bike has a belt drive not a chain and the back sprocket looks like it is aluminum. The other parts are probably steel based but not sure. It could be aluminum too, which would somewhat complicate the recycle steps.

The cardboard would have a problem recycling because of the resin for the binder, that complicates recycling, as opposed to vanilla cardboard from grocery stores, for instance.
antialias_physorg
not rated yet Oct 24, 2012
There's several ways you can do this: Aluminium and copper are usually not 100% pure so susceptible somewhat to being extracted via magnets. The stuff is shreddered very small and if you've seen the magnets they use in these sort of sorting facilities... well...I wouldn't bring my credit card for a tour.

Modern, automatic sorting of non-magnetic materials works mostly via the differing specific weight (i.e. just dumping the shredded stuff into a basin of water and having it separate accoring to how far/how fast it sinks). This is done in a continuous process.

As a last method you can just burn everything and collect what's left over.

The hardest stuff to recycle is actually things like milk cartons (because they are laminated plastic, metal and paper layers)
Mike_Massen
4.3 / 5 (6) Nov 06, 2012
Eddy effect separators handle non-ferrous rather well though there are issues with power consumption. After shredding, vibratory columns can work with almost all metals, glass, ceramics reaching the bottom, aluminium foil in things like tetra paks arent worth the trouble, not yet likely to worry about that many tetra paks though affecting level of easily recoverable metals in ash. Depends on volume if worth doing for combustion though, a switched on plant manager will rerun their spreadsheets whenever source costs undergo change...

TheGhostofOtto1923 could be rather more precise and understand an 'effective' composite doesn't start out as a composite just because there are other materials - huh ? OttO ? It becomes that by way of a different process etc How can I possibly know something is manageable TheGhostofOtto1923 *doh* its obvious, one manages, one has a goal and addresses well known processes to achieve the intended result tis not rocket science you know TheGhostofOtto1923