# If you can make a cycle frame from flax, could you make one from hemp?



## Yellow Fang (7 Dec 2011)

Several years ago, I read an article in Cycling Plus about a road cycle frame made mostly from flax with a bit of carbon fibre. I believe it was a Museeuw frame.

Now I see Schwinn have made a cycle frame entirely out of flax.

I am currently reading a book about hemp. Its fibres are at least as strong as flax. It's pretty hard to tell them apart, although one way is to wet it. On drying, flax will twist clockwise and hemp will twist anticlockwise. If it is possible to make a bicycle frame out of flax, then surely it is possible to make one out of hemp.

(Hemp is such an incredibly useful plant, but is illegal to grow without a licence in the UK because people like smoking some forms of it. Hemp's other names are cannabis and marijuana. Marijuana is really the drug, while hemp is the name of the fibre as well as the plant, like cotton. According to the author, the plant was banned in the US because the US Tresury Secretary, Andrew Mellon was also a major financial backer of the DuPont petrochemical company. He perceived hemp as a threat to his business interests because it was a cheap source of cellulose from which plastics could be made. Another scumbag in the conspiracy was William Randolph Hearst, whose company used Du Pont's chemicals to make paper. He was was also a major logger. Paper from hemp is better quality than paper from wood pulp, and you can get four times as much per acre of land. Hearst owned a newspaper chain and ran loads of scare stories about Mexicans getting high on marijuana and going on violent rampages. Another of Mellon's allies was Harry J. Anslinger, who was appointed head of the Federal Bureau of Narcotics. Anslinger collected any newspaper scare story he could find about marijuana, and when that wasn't enough, fabricated some more. Then they effectively got the drug banned by dressing it up as a revenue tax bill, so that it could be rubber stamped by other allies without it undergoing discussion in the full house. By the time hemp farmers were aware of what was going on it was too late to stop it. One reason why the hemp industry were slow to react was because they were not aware marijuana was hemp. Marijuana was a name picked out for the drug by Hearst, taken from a Mexican song. Industrial hemp had very low concentrations of THC, the chemical that makes you high. The way it was farmed entailed cutting it down while it was still green and laying it out on the ground for a few days to get wet, a process called retting. By the time it had retted, the leaves had fallen off, so there was no THC left. The book does not explain why hemp was banned in so many other countries, except that Anslinger was involved in drawing up the UN Single Convention Treaty on Narcotic Drugs in 1961.)


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## Gareth (7 Dec 2011)

I have built prototype frames from flax and from hemp and from a 50-50 combination of the two, in association with the Incrops team from the UEA.


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## Yellow Fang (7 Dec 2011)

Gareth said:


> I have built prototype frames from flax and from hemp and from a 50-50 combination of the two, in association with the Incrops team from the UEA.


 
Can you tell us any more?


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## Gareth (7 Dec 2011)

No, and I may have said too much already.


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## MontyVeda (10 Dec 2011)

now that is a nice looking bike


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## dan_bo (10 Dec 2011)

Gareth said:


> No, and I may have said too much already.





Ooooh you big tease.


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## Vikeonabike (17 Dec 2011)

Planning on building a bamboo bike after xmas..may be using hemp and resin to hold it all together...although I would prefer carbon tow and resin as it looks better.


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## Red Light (17 Dec 2011)

Yellow Fang said:


> Several years ago, I read an article in Cycling Plus about a road cycle frame made mostly from flax with a bit of carbon fibre. I believe it was a Museeuw frame.
> 
> Now I see Schwinn have made a cycle frame entirely out of flax.
> 
> I am currently reading a book about hemp. Its fibres are at least as strong as flax. It's pretty hard to tell them apart, although one way is to wet it. On drying, flax will twist clockwise and hemp will twist anticlockwise. If it is possible to make a bicycle frame out of flax, then surely it is possible to make one out of hemp.


 

You could make one out of hemp but while hemp has the same specific stiffness as flax (stiffness to weight ratio) it has a much lower specific strength (strength to weight ratio). Of all the natural fibres, flax is the best one to use for a composite.

I'm wondering if the Schwinn tubing comes from these people?


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## Yellow Fang (19 Dec 2011)

Red Light said:


> You could make one out of hemp but while hemp has the same specific stiffness as flax (stiffness to weight ratio) it has a much lower specific strength (strength to weight ratio). Of all the natural fibres, flax is the best one to use for a composite.
> 
> I'm wondering if the Schwinn tubing comes from these people?


 
Where did you get your information?

It does look like flax fibre is slightly stronger to hemp fibre. The Youngs Modulus for flax fibre is 58GPa, while for hemp fibre it is 35GPa.

http://en.wikipedia.org/wiki/Young's_modulus

Although another source says the Youngs Modulus is 18.4GPa for hemp filbre and 21.4GPa for flax. Tensile strength is slightly better for flax (512MPa) than for hemp (507MPa).

http://www.fidiaglobalservice.com/eng/tessuti_lino_canapa.html

I read another document that says hemp yarn has a tensile strength of 550 to 900MPa, but it does not give the figures for flax.

http://www.ijimt.org/papers/130-M534.pdf


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## Yellow Fang (23 Dec 2011)

Again it seems like flax is a stronger fibre than hemp, but hemps seems to be the best of the rest.


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## Yellow Fang (23 Dec 2011)

Most of the reports I've read seem to compare natural fibres against glass fibre in composites (such as fibreglass). I wonder how it compares against carbon fibre. You get cars and boats made of fibreglass, but I've never heard of a bicycle made of fibreglass.






The other part of the composite seems to be a plastic like polypropylene. I wonder if polypropylene could be made from hemp hurds, which is a rich source of cellulose.


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## dellzeqq (23 Dec 2011)

two young women turned up to an FNRttC with bikes made out of bamboo and carbon fibre sticky tape that they'd made themselves. I can tell you, we were darned impressed.

http://bamboobikestudio.com/


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## Yellow Fang (23 Dec 2011)

Every time I try and find a report with some numbers that compares hemp fibre to flax, flax is stronger (sigh).






Spider silk is surprisingly strong, though a bit stretchy. It doesn't look like any natural fibre can compare to carbon fibre though. That really does look like the stuff. I suppose that is why the Museeuw decided to keep a proportion of carbon fibre in their frames: carbon fibre in the high stress areas and flax for the rest.


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## Yellow Fang (29 Dec 2011)

dellzeqq said:


> two young women turned up to an FNRttC with bikes made out of bamboo and carbon fibre sticky tape that they'd made themselves. I can tell you, we were darned impressed.
> 
> http://bamboobikestudio.com/


 
Looks like fun, as well as theft proof.


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## seadragonpisces (3 Mar 2012)

MontyVeda said:


> now that is a nice looking bike


 
Here it is in the flesh, my one (Schwinn Vestige)


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## steveindenmark (8 Mar 2012)

I have been working on the "Flax Capasitor" with the Doc. We are aiming to get it working below the standard 88mph, the speed which it has operated at since 1955.

But like Gareth, I think I may have said too much already. 

Steve


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