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[Closed] Would you buy a bike made from recycled carbon fibre?

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With an estimated 3000 tonnes (6.6 million lbs) of carbon fibre composite (CFRP) scrap (so-called ‘black junk’) being generated annually in the USA and Europe, some 6000 to 8000 commercial planes expected to reach end-of-life dismantlement by 2030, and the production of virgin carbon fibre (VCF) on the rise toward 100 000-plus tonnes (220 million lbs) annually by 2018, something’s gotta give. Where will all this black junk go?

For any company involved in the development of the CFRP recycling industry, there is a performance perception problem to be dealt with. This is the idea that recycled carbon fibres are of secondary or “lesser than” quality than VCF

Plenty of people doubt CF for DH bikes, and MTBs in general. Would you expect your expensive bike to be made from virgin carbon fibre? Would you ride one that wasn't?


 
Posted : 25/08/2010 10:33 am
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I'd be interested to see how it was achieved. Part of my love of CF is the look of it (being able to see the weave) but assuming I'd accepted that may go with recycled CF, and assuming they've proven it's as capable as VCF, only a muppet would demand VCF.


 
Posted : 25/08/2010 10:37 am
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Assuming it has the same properties as new stuff yes why not?


 
Posted : 25/08/2010 10:43 am
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The weave is almost always just a cosmetic layer on top of the 'proper' structural cf below so you could have a recycled frame that still had weave on show.

Presumably recycled cf will be short strand stuff so inherently not as good as the more expensive longer strand cf but as I understand it short strand is in use in bikes so it shouldn't be any worse than that - eg it'd be fine.


 
Posted : 25/08/2010 10:45 am
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I'd have thought short strand stuff would be more used in places like boat building where weight is important, but not that important?


 
Posted : 25/08/2010 10:48 am
 cb
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Presumably the length of the fibre for recycled cf will be dependent upon the process used to reclaim the material at the end of service (1st time around)? Have no knowledge of the mfg process - do they use a resin to bind the material or is it just heat that is used?


 
Posted : 25/08/2010 10:49 am
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he weave is almost always just a cosmetic layer on top of the 'proper' structural cf below so you could have a recycled frame that still had weave on show.

Not on any of the stuff I've made 🙂


 
Posted : 25/08/2010 10:51 am
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Won't the novelty of seeing the weave wear off? Has for me anyway.


 
Posted : 25/08/2010 10:54 am
 tron
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I reckon this is a problem that will solve itself.

At present, carbon fibre is used mainly for Carlos Fandango bits, and as far as I know, laid up by hand. As a result, the cost of carbon parts is going to be heavily weighted towards the cost of the labour making them. Saving a few bob on recycled carbon isn't going to be a great move, particularly if it means more weight.

Once carbon stuff starts being commonplace, and mostly machine made, we'll see recycled carbon fibre become more useful. The savings on materials will be more worthwhile, and there'll still be a weight advantage over stuff like glass reinforced nylon.


 
Posted : 25/08/2010 10:57 am
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Won't the novelty of seeing the weave wear off? Has for me anyway

That's a good point. It's not quite as futuristic anymore.


 
Posted : 25/08/2010 11:00 am
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Carbon Fibre Reinforced PLASTIC (CFRP)
Is it the plastic that is being recycled or the fibres?

"do they use a resin to bind the material or is it just heat that is used? "
http://www.substech.com/dokuwiki/doku.php?id=carbon_fiber_reinforced_polymer_composites

Some CFRP has as much as 70% carbon fibre in it, the rest can be thermo or thermosetting plastic.

Some people can be a bit fussy about the materials they use
http://www.formula1.com/inside_f1/rules_and_regulations/technical_regulations/8697/fia.html
"10) Thermoplastics : monolithic, particulate filled, short fibre reinforced.
11) Thermosets : monolithic, particulate filled, short fibre reinforced.
12) Carbon fibres manufactured from polyacrylonitrile (PAN) precursor. (*)
13) Carbon fibres manufactured from polyacrylonitrile (PAN) precursor which have :
- a tensile modulus ¡Â 550GPa ;
- a density ¡Â 1.92 g/cm ;
- unidirectional or planar reinforcement within their pre-impregnated form, not including three dimensional weaves or stitched fabrics (but fibre reinforcement using Z-pinning technology is permitted) ;
- no carbon nanotubes incorporated within the fibre or its matrix ;
- a permitted matrix, not including a carbon matrix."


 
Posted : 25/08/2010 11:00 am
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CF layup isn't that labour intensive TBH, and most of it is done in china where labour is cheap as chips, it takes time and heat to cure which is one problem, and the materials are pretty expensive. Last time I bought some it was (for the cheapest grade I could find) £25 per metre, a metre wide.

Won't the novelty of seeing the weave wear off? Has for me anyway.

No, I don't think so. I love the look of carbon bits, especially wet carbon.


 
Posted : 25/08/2010 11:01 am
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This is the article I was quoting from, quite long but covers the main processes at present.

http://www.reinforcedplastics.com/view/8116/launching-the-carbon-fibre-recycling-industry/


 
Posted : 25/08/2010 11:05 am
 tron
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china where labour is cheap as chips

That'll soon be "was cheap as chips" 😆


 
Posted : 25/08/2010 11:14 am
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That'll soon be "was cheap as chips"

At which point production will move to Africa, which is kinda (economicaly/politicaly) where China was 20-30 years back (unstable/unsavoury but getting better, and an endless supply of cheep labour.

The difference is it will be the rise and afluence of Chinese middle classes not Western middle classes that drives this.


 
Posted : 25/08/2010 11:25 am
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There's an awful lot of poor Chinese people to keep unskilled salaries down but of course the unions won't allow that. Fair enough but I wonder how things will work out there as the better off get richer and the poor continue to scrape a living.


 
Posted : 25/08/2010 11:54 am
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Not so long ago Carrots were the future
http://www.bikebiz.com/news/25734/Carbon-fibre-famine-could-be-ended-by-carrots

Complete the following: Snap like a C.....

But recycling plastic should be commended, although its more likely to get burnt in a power station like some old tyres are.


 
Posted : 25/08/2010 12:55 pm
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http://www.guardian.co.uk/environment/green-living-blog/2010/aug/24/racer-rosa-bicycles-bike
"If you've bought a high-end bike from a big name manufacturer recently, then it may well have been air-freighted and its production certainly involved planet-damaging chemicals – particularly so if it was made from carbon fibre."


 
Posted : 25/08/2010 2:09 pm
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"Multinational bike companies are like McDonalds. They produce disposable products for maximum profit."

Ouch! He has a point though.

Has anyone seen a bike manufacturer offering recycled alu frames? The energy required to recycle alu is apparently only 10% of that required to make virgin alu.


 
Posted : 25/08/2010 2:37 pm