DIY Carbon fibre frames?

LockH

LockH

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Ummm.. Started out in Victoria BC Canada, then sta
Hehe... ESB "Search found 3191 matches: +carbon +fiber".

American company ALLIED CYCLE WORKS ("a brand by HIA Velo") in Little Rock, AR shows us how it's done.

ALLIED CYCLE WORKS: Lifting the curtain on carbon fiber
[youtube]XMnegeYuLW4[/youtube]
 
Lots of work and equipment required to make a simple road bike frame, and they don't show the research and testing in the development process. Now with the higher requirements of a FS high speed bike, it does make it a long process and a big investment that is only affordable to the big players. I'd say: I you want to make your own custom frame, metal work is much cheaper, simpler, easier... With much better chances of a successful first attempt.
 
Hehe... OK, OK... "DIY" was a "bit of a stretch". :wink: EVen in this vid they reference to the MANY hours spent in "development"... aka "trial and error". Still nice to see NA folks helping to "lead the charge" towards "smaller", "light-weight" vehicles. ... and as usual in manufacturing, higher volumes of units sold tends to "push" selling prices lower. :)
 
The only DIY part of their shop was the lack of an autoclave. I liked how they made sure to use every bit of the pre preg roll. No wasted material. Yes carbon fiber is time consuming, but I got to say carbon fiber is a material that is actually very nice to work with even for the DIY crowd. Even without an autoclave you get perfect result when using vacuum bagging like they did. Most DIY project probably would not be able to use pre preg carbon fiber, but the use of vacuum bagging ensures that the resin is drawn in correctly and spread evenly. Vacuum also remove air bubbles and help with perfect layer bonding. Prices on carbon fiber has really dropped that past decade and is now really affordable.

Biggest problem for DIY crowd is that the time and effort to make a great mold. And when mold is finally done the polishing and prepwork to get it ready for use can be daunting. The nice thing is that when the mold first is made, you can re coup some money by making more then one frame or whatever carbon fiber part you are making and sell what you don't use.

I guess if you are a skilled 3D designer you could draw up the mold in 3D and have it CnC machined with very high level of accuracy. That should cut down on the labor intensive pre work of the mold.
 
I used to build using carbon fiber for custom projects. Kayak's was popular for a while. Also we did some custom car parts and various racing parts in cf.

You got to remember that many of the manufacturers that build cf frames have one overall goal. Lightest possible weight. Secondary goal is to make money. Often those two goals don't blend well if the parts needs to be heavy duty for tough use. I think that wrong focus is the main issue with cf frames. Either by cutting corners to save on man hours, or by using cheap products or fake products like no brand cf and china resin.

I can asure you, it is not that cf is complicated or weak. In fact entire wheels are made out of cf these days, lighter and stronger then even the best magnesium alloy racing wheels. And you can get those DOT approved as well. In racing cf has proven useful even for drive shaft for hi torque engines with launch control. And that launch control takes a toll on all moving parts.

If you do your mold right, the prep work right you then just need to make sure you are choosing the right number of layers to get the strength you need. We already had a home made cf frame here at ES several years ago, they guy who did Phasor frame maybe?? He did 6 foot drops onto flat land without any issues with his cf frame. Ride it like he stole it and bike held up.

If you ever worked with fiber glass you got skills to master cf. Easier then you might think. And stronger then steel when cured.
 
Alan B said:
So many commercial CF bike frames have failed in service, I think making your own is taking great risks.
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Hehe... And I might suggest that in the history of "new tech" there has been lots of folks trying "stuff" based largely/only on their tools and experience working with "old tech"?

As a sailor, my first "whisker pole" (used to pole out a "jib" foresail to go "wing-on-wing" "down" wind/in the same direction as the winds) was made of wood w/plastic end pieces, though my last whisker pole WAS CF. Sorta super light-weight, and never broke. Didn't even bend. Can guess it was made (hollow) on a simple metal mandrel. :)
 
I have no doubt about CF advantages, but someone building a first bike frame with CF is likely to find the learning experience very expansive if he want to achieve structural and finish quality. Once in the resin, CF can't be recycled. Every try does require starting over with new material. Then, layering fibers without quality testing can produce too weak or too heavy, or both. My guess is that I would spend the price of a good frame long before succeeding to produce one that I find barely acceptable. Just making a good mud guard did require a lot of time and money, and even though I am satisfied with the finished result it does weight more than Alu.
 
Spinningmangnets, I would be very careful working with cf without the use of an autoclave or vacuum bagging. Weakness in CF constructions are more often then not caused by delamination. Especially in complicated curves in a structure there can be complicated to get the cf saturated with resin. If there is air trapped, or saturation is not complete the inner structure of the construction will degrade and decay and will inevitable fail.

Why does this happen? Unskilled, lazy workers, to tight schedules to give crew enough time to do the layering correct, too fast curing or not curing correct or fake or bad products to save pennies.

Vacuum bagging draws resin into all the layers, soak thru and excess resin goes in the evac bin. While under vacuum the bonding of layers are optimal and evenly compressed. Any trapped air or bubbles get drawn out and leaves a super layered structure that will stay bonded even under heavy use.
 
Option: Hire someone who can draw up a 3d program . I think there are many people these days that can do that .

BTW.

I see Carbon as the Material that should be used in the , Not Yet Designed/Made , more upright seating and comfortable, Velomobiles that many of us want.

over 10 years ago I saw a article on the internet where someone in Phoenix AZ. I think, had made his own carbon fiber recumbent bike. DIY at home, sure it was heavier than professional made , but it worked fine and was probably very strong.
Carbon Frames can be made very strong when laminating in different directions for the different layers .
And from past video's I have seen, making your own in home/garage vacuum bag is easy.






macribs said:
I guess if you are a skilled 3D designer you could draw up the mold in 3D and have it CnC machined with very high level of accuracy. That should cut down on the labor intensive pre work of the mold.
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MadRhino you are correct, the amount of work for a one off in cf compared to alu or steel is crazy. And the hours needed to make that one off better come off your free time or the end result will be very expensive. But that is the thing with DIY. If you can spread things out over several months and can do the work yourself without loosing money or your wife, that I say I might very well be worth it in the end.

I've seen men buy old rotten wooden sailboats nobody ever thought was gonna roam the sea again. 10-15 years later the former wreck has transformed into a true aye candy of a restored beauty. All rotten wood replaced, carefully crafted by hands or with minimal profession tooling. The overall cost of this transformation might not be much in nickel and dimes, but count in the endless long nights, the loss of two divorces, and the the final bill often adds up :)

The nice is that if they make it come together and it turns a beauty suddenly there is even a resell value. That would hold true for a custom made cf e-bike too. If you succeed and have the stamina to power thru the hard work not many others will do what you just completed. And thereby many will be willing to part with their money to have your ride.
 
Just going to leave it here. I'm sure it's all been considered but if this is an offroad bike you will eventually put stress on the frame. If that starts to show visibly your at risk of losing the entire frame. Once it's been roughed up at all that's it.
 
I think you need to see the difference between an e-bike carbon frame and those tiny walled racing carbon frames for the lycra riders. In the early days of carbon frames a few lycra riders had carbon frames split on them. But that was not because carbon fiber is bad. It was all due to poor fabricating, rushing production and not removing trapped air in the laminates. The guy behind the Phasor frames had the first carbon fiber frame e-bike here on ES. He rode that thing like he stole it. Fat hub, big battery. Regularly doing 4-5 feet drops. Jumping etc. Frame held up fine.

Point is layer up in stress areas. Don't chase the grams. Make the frame for longevity rather then paper thin super light. After all you will bolt on battery, motor, controller and possible even mc rims. If you feel the thick walled carbon fiber is too heavy I recommend a 3 month subscription to the local gym with cardio and power lifting until you dropped body weight matching your dream target frame weight. If a strong carbon fiber frame weigh in at say 10 kilo, and you are dead set upon max 5 kilo, leave the frame at 10 kilos and remove those 5 kilos from body weight and ride a carbon frame super structure.

Check the with the various NYX owners here on the forum. Some of them running 20-30 kw motor(s). Yes even dual drive. AFAIK no frame fractures yet.
 
macribs said:
Make the If you feel the thick walled carbon fiber is too heavy I recommend a 3 month subscription to the local gym with cardio and power lifting until you dropped body weight matching your dream target frame weight. If a strong carbon fiber frame weigh in at say 10 kilo, and you are dead set upon max 5 kilo, leave the frame at 10 kilos and remove those 5 kilos from body weight and ride a carbon frame super structure.
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Hahaha! These are words to live by. I dropped 10 lbs of body fat in the last month and a half and all of my mountain bikes feel lighter because of it.
 
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