Chapter 2 Carbon Fiber Bike Build.wmv

[circusboy90210]

polystyrene? why not leave in intact this would be stiffer then.

[TheProjectJunkie1]

@circusboy90210

I didn't remove the polystyrene from all of the tubes. I left it in the seat-tube and most of the top-tube. I mainly took it out in places I needed to run the internal cabling. I thought it would save in weight but I think the weight savings was negligible.

[circusboy90210]

@TheProjectJunkie1 yes and the styrofoam is tremendous for extra strength, aviation uses it in a sandwhich operation to vastly increase strength.

[TheProjectJunkie1]

@circusboy90210

That's exactly how the wings are made on the Q200. It's just polystyrene wrapped in fiber glass- Super light and super strong.

[circusboy90210]

@TheProjectJunkie1 would like to add a layer of titanium honeycomb over the polystyrene myself . carbon fibe does not seem to take shock very well on it's own . f1 cars use some metal in the frames.

[TheProjectJunkie1]

@circusboy90210

Good Heavens! You must have some deep pockets but I like the ingenuity:-)

[circusboy90210]

@TheProjectJunkie1 not as expensive as you might think. dome some research only talking about a sheet a half inch thick at most and a qaurter inch everywhere else. 747's use this why not for everything else? still trying to find actual numbers for flex modulus etc tensile strength. my estimate is from it's application in other areas. however if the plane ends up costing $90k in materials that's no big deal . building this will give me leverage to borrow capital for other projects.

[TheProjectJunkie1]

@circusboy90210

If you're going to use this type of laminate then you could probably just make a monocoque wing without a core. You still may need a spar but I think most gliders are using this type of method now.

[circusboy90210]

@TheProjectJunkie1 forgot to mention self employed here. income is only limited by imagination in these great united states. unless being successful and rich is further demonized by those too lazy to get their own .

[circusboy90210]

just curious what's the difference between out of autoclave and vacuumbagged parts as far as strength modulus etc..

[TheProjectJunkie1]

@circusboy90210

I don't know the strength differences for sure, but using an autoclave produces superior parts because it removes bubbles in the laminate. To compensate you have to use more carbon fiber on non-autoclaved parts. I don't think the difference is that big but Polystyrene will crush if too much pressure is applied. I've had this happen with using too much pressure in vacuum bagging. I try to stay around 20"HG when vacuuming it.

[AZURA888]

My carbon fiber fabric comes around December 20-26, so I'm waiting for Santa, I'm practicing meanwhile with fiber glass, other question, the wood core you used here as pattern was first covered with release agent true?,was it hard to separate the carbon piece from this?, because is not like the Z frame wher the carbon piece was molded in two parts.

[TheProjectJunkie1]

@AZURA888

I don't think I use any wood on or in this bike. The pink plug or core that you see me wrapping is 2lb per cubic foot Extruded Polystyrene Foam made by Owens Corning- It is insulation foam. Dow also make this foam but the color is blue. This type of construction, with a foam core wrapped in a fiber reinforced plastic, is how a lot of composite airplanes are created. It produces a strong yet lightweight structure-I left the foam in some tubes and burned it out in others using acetone.

[AZURA888]

Thanks, I don't know but I remember that I saw a show in discovery "how it's made" about doing rings and rods in carbon fiber, a guy rolled each one inside an aluminium mold, I think is easier to do just a disk as wheel.

[TheProjectJunkie1]

@AZURA888

The video you watched shows the bladder and clam-shell method. Most bike manufacturers are using some variation of this method now. If you did a monocular disk wheel, you'd probably have to make it in 4 molds that fit together. You could use the axle hole as the inflation point. Then hopefully you can use this point as a way to get the bladder out too. It will be a tough project but I have faith in you :-)

Good luck and keep me posted!

[AZURA888]

@TheProjectJunkie1 oh thanks, I will buy the fabric to begin, your vids will really help me, if the mine results as your frame it will be perfect. Which is the price of CF yard there?. Here is 46US$ the m2.

[TheProjectJunkie1]

@AZURA888

The cost of carbon fiber cloth can vary greatly depending on the kind your considering (e.g. weave type, tow size, weight, modulus, manufacture, etc.). $46 m2 isn't the cheapest you'll find but it's not on the high end either. Best thing to do is shop around.

[AZURA888]

that is like to roll sushi. how many mts2 takes to do a frame?.

[TheProjectJunkie1]

@AZURA888

LOL! I love sushi.

Sorry I can't make out what you mean by "mts2" ?

[AZURA888]

@TheProjectJunkie1 which is the area per square meter m2 of carbon fiber that takes to build a frame. I think that 1,8m2.

[TheProjectJunkie1]

@AZURA888

If I remember correctly... I used about 2 yards of 50" cloth. So about 2.7yd2 or about 2.3m2.

[LxTxSURGE]

is this easy to make and build

what whas the cost of the bike like in materials

im trying to make my own carbon fiber disk rear wheel

you think you can make one

or will it be easy

[TheProjectJunkie1]

@LxTxSURGE Building a bike wasn't as hard as I thought it was going to be. However, the build took a lot longer than I had expected. A lot of time was from doing research- That is why I documented everything, so others didn't have to as much. The Frame Cost about $160 in materials. I've thought about making a cf wheel, but in order to make a decent one there would be a lot of work and the process seems too big an adventure for me right now. It's a great project so let us know how yours turn out.

[LxTxSURGE]

@TheProjectJunkie ok here is my plan i'm just going to use a stock rim and cover it with some carbon fiber like one of those home made discs but

i have to order the sheets and then cutting and molding them into the right shape

so will that be hard and expensive

[TheProjectJunkie1]

@LxTxSURGE

If you're just making covers it wouldn't necessarily be as hard to make as it would be time consuming. You'll have to build two different molds since the rear wheel's spokes aren't the same on both sides- the cassette creates an offset. Your fist set is going to be expensive and then each set after that will probably cost around $75 just in materials. $90 can get you a decent wheel cover- Search "Aero Disk Cover." But if you want a good and challenging project I say go for it.