working with carbon fiber?

Discussion in 'The Garage' started by scorch, Sep 16, 2008.

  1. Gumbydave

    Gumbydave motorcycle doofus

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    here is a carbon fiber side panel i made for the 07 GS to cover the TPS

    Just find some CF cloth and 2 part epoxy resin such as "West Systems" Make a positive mock-up using bondo spread over some expanded aluminum screen for home ventilation, use duct tape also . sand the bondo smooth then cover the positive mock up with non-abrasive car wax, mold over the positive using inexpensive polyester resin and fine weave fiberglass cloth remove the positive from the mold and wax the mold, lay up some CF fabric well soaked with the two part epoxy. Sandwich the part in the mold between two layers of polyuethane plastic sheet, seal the edges down with window sealing putty rope, insert a vacuum pump and leave it run unbtil the epoxy gels
    Remove the part, grind the edges and install

    nothing to it

    [​IMG]
    #21
  2. DELTATANGO

    DELTATANGO Motorcyclist and Dog Walk

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    Nothing to it:lol3
    #22
  3. Donkey Hotey

    Donkey Hotey De Jo Momma

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    :lol3 No shit. It's just like the instructions to sculpt an elephant:
    1. Get a very large piece of marble
    2. Remove everything that does not look like an elephant
    Easy peezy. :deal
    #23
  4. drhach

    drhach We can't stop here, this is bat country!! Supporter

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    You're getting a lot of free advice here. I think the truth of the matter lies somewhere between "you'll poke your eye out" and "it's really easy". I assume that you are going more for looks than any kind of weight savings. Yes? If that is the case, you probably can skip all of the BS about prepregs, autoclaves etc, etc. The part that you want to make has a very simple shape. Honestly, you could nail a couple of boards together that have those bends in them. Nail a couple more together that have the same bends again. the two would form a sandwich that you could press your layers on to and there ya go. Clamp it togetrher overnight, cout out the shape, spray a clear coat over it and your good to go. Try it. ou'll learn something, the part will look pretyt cool and it'll probably be fun. Most important, be safe. Modern epoxies really aren't too bad as long as you work in well ventilated area. Whatever you get on your clothes will be permanent. Wear rubber gloves. The most dangerous thing is any dust from grinding or cutting the fabric. For that, wear a dust mask.

    Check out www.fibreglast.com. They sell small batches of epoxy and you can also buy "sample" sized fabric quantities. They also have a forum where you can ask all kinds of questions. I'm not affiliated in any way, just happy customer. Good luck, post pictures when you are done.
    #24
  5. Inane Cathode

    Inane Cathode Cheated Anion

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    Is carbon fiber a suitable material for making more structural components like rear set brackets and the like?
    #25
  6. bomber60015

    bomber60015 tikkun olam Supporter

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    you can make damn near anything outa cf . . . . . witness F1 tubs and aircraft bodies and the like

    if you're gonna sand the stuff, though (edges, where the CF strands are exposed from the resin), wear some decent gear -- that stuff ain't good fer yer lungs
    #26
  7. Inane Cathode

    Inane Cathode Cheated Anion

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    Another question. For the structural pieces, and cf in general, is the vacuum bagging process extremely important or can it simply be pressed into shape? Is it that important at all for a piece to be pressed or vacuum bagged or is that more for weight savings?
    #27
  8. dhubbard422

    dhubbard422 Adventurer

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    It has been a while since I worked with carbon fiber... I built race cars in the early 80's and things (epoxies, in particular) may have changed a little bit in the last 25 years. But, based on my experience, the epoxies used to glue carbon together and to shape it into a form are very, very nasty. They are hard on the lungs and skin. Use a professional respirator to protect your lungs. Wear a tyvek suit to protect your skin. Wear goggles to protect your eyes.

    It's worth repeating... finishing the part after it has been laid up is the most toxic step in this process. Avoid all contact with carbon/epoxy grinding dust! Eyes, lungs, even the pores of your skin should be completely covered.

    You can work with carbon fiber and epoxy much like fiberglass (lay the sheet material in the mold and then saturate it with epoxy via a brush) or you can work with pre-pregs (pre-glued sheets that activate the expoy via heat. Ovens, vacuum bags and even autoclaves can be used to create lighter and stronger parts. You might use an oven to control/activate the epoxy glue. You could vacuum bag the part to remove excess epoxy; the atmospheric pressure also increases the strength of the bond. And an autoclave could be used to increase the pressure above that of one atmosphere; structural parts may require the pressure of an autoclave for sufficient strength.

    Expect a lot of trial and error to get parts that are professional looking and professionally crafted. As previous posters have indicated, creating one off parts in carbon fiber is usually, fairly expensive.

    I feel I shouldn't sound so negative... it is very cool to finally get a professionally crafted carbon fiber part. The bling factor can be very high.

    Hope this helps.
    #28
  9. Mikas

    Mikas Been here awhile

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