composite materials and pvc forms

Discussion in 'Fiberglass and Composite Boat Building' started by cattlehound, Jan 29, 2011.

  1. cattlehound
    Joined: Jan 2011
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: new zealand

    cattlehound New Member

    having done several hours reading and researching I have some idea of what I want do. I would like to form 2 identical 6' long, 2" OD (roughly) tubes out of Carbon Fiber (with an arcing profile). after toying with some ideas I thought...

    Using PVC bent under load, lay up a glass sock or sleeve over the top (applying pressure with heat shrink tubing?)... wait for an intermediate cure.

    Carefully cut the glass fiber away from the pvc and use this as a form for laying up carbon fiber (as per my requirements, not important for this post)

    Question, would a vacuum and or heat shrink cause the glass (at only 1 ply thick) to implode / crack / deform, under the carbon fiber layers? Is this a terrible idea, ie would the thickness of glass required to hold up to vacuum negate the weight loss of using carbon all together?

    further thought... joining two or more curves made this way, with straight tube and or what ever you might need, at the glass stage could produce a very clean, tidy form for CF tubes (depending on all the applicable strand orientation / epoxy / thickness variables)

    Any thoughts greatly appreciated...
     
  2. Mr Efficiency
    Joined: Oct 2010
    Posts: 7,390
    Likes: 233, Points: 63, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    I'm stuck on understanding what this vacuum stuff is all about, in fact I have " NFI " ! :confused:
     
  3. cattlehound
    Joined: Jan 2011
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: new zealand

    cattlehound New Member

    sorry, long day at work.

    having formed a fiber glass tube with the bend I need, I could vaccum form layers of CF over the top (or use heat shrink tubing to compress the composite-resin matrix to remove excess epoxy).

    If that makes sense... Imagine two or more curved tubes of glass sleeve joined, then vacuum form a nice, smooth, consistent double curve carbon fiber laminate tube ;)
     
  4. Herman
    Joined: Oct 2004
    Posts: 1,614
    Likes: 88, Points: 0, Legacy Rep: 1240
    Location: The Netherlands

    Herman Senior Member

    If you don't envelop the whole structure in a bag, you could get away with it. However, keep in mind that 1 layer of cloth very likely is not vacuum tight.
     

  5. rwatson
    Joined: Aug 2007
    Posts: 5,783
    Likes: 265, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    How are you going to 'carefully cut the glass layer away from the PVC" ?

    The bond is really good - it would be a case of grinding it away.

    What would be the problem with just hand laying the glass over the PVC for your 'former' ?
     
Loading...
Similar Threads
  1. KnottyBuoyz
    Replies:
    0
    Views:
    1,635
  2. fallguy
    Replies:
    6
    Views:
    486
  3. Steve W
    Replies:
    17
    Views:
    842
  4. massandspace
    Replies:
    2
    Views:
    466
  5. pescaloco
    Replies:
    0
    Views:
    1,062
  6. JimmyR
    Replies:
    3
    Views:
    1,138
  7. longcours62
    Replies:
    1
    Views:
    1,088
  8. isvflorin
    Replies:
    7
    Views:
    1,626
  9. ankitnehra1990
    Replies:
    28
    Views:
    2,631
  10. robwilk37
    Replies:
    26
    Views:
    3,911
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.