Peel ply

Discussion in 'Techniques' started by rocketcharlie, Aug 11, 2019.

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  1. Aug 11, 2019 #1

    rocketcharlie

    rocketcharlie

    rocketcharlie

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    Hi all,

    I just started tip to tip lay up on a 54mm MD project. I thought I understood that when you apply the peel ply to the resin you wet the peel ply in as well. I applied resin on top of this material just as I did with the fiberglass cloth. Now I am questioning this. If I am wrong what is the best way out of this debacle?
     
  2. Aug 11, 2019 #2

    JimJarvis50

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    If you want to "finish" the epoxy to a smooth finish after you remove the peel ply, then you can apply some epoxy to the top of the peel ply if there isn't enough to wet it out from below. Try that first, then add extra if necessary. It is helpful to remove the air from below the peel ply. One trick to do this is to use the tip of a chip brush, perpendictular to the layup. Just tap/tap/tap and the air comes out.

    Jim
     
  3. Aug 11, 2019 #3

    rharshberger

    rharshberger

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    Usually the peel ply will draw up the excess resin from the layup wetting out the peel ply, odds are if you see any dry spots after smoothing out the peel ply there are spots in the layup that didn't get properly wetted out.
     
  4. Aug 11, 2019 #4

    rocketcharlie

    rocketcharlie

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    So since I have put a full coat of epoxy on top of the peel ply, what will happen when I try to remove the peel ply? Will it be too hard and stiff to remove ?
     
  5. Aug 11, 2019 #5

    rharshberger

    rharshberger

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    It should still pull away, maybe a bit stiffer.
     
  6. Aug 11, 2019 #6

    rocketcharlie

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    Good deal, you are making me feel better about this
     
  7. Aug 12, 2019 #7

    rocketcharlie

    rocketcharlie

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    OK, so thanks to the help of this forum I have successfully removed the peel ply from my project. The peel ply leaves a textured surface. Would anyone tell me the technique you use to get a nice smooth surface on fiberglass?
     
  8. Aug 12, 2019 #8

    rharshberger

    rharshberger

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    Are you painting the FG? If so sand, prime, sand, prime, sand...until its good then paint. If not painting I sand (but not into the FG fabric) then apply another coat of clear epoxy.
     
  9. Aug 12, 2019 #9

    rocketcharlie

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    Yes I will be painting it. So enough coats of primer followed by sanding and it will fill in the surface, got it. Just for my own education in the case of not painting you just use a brush to spread a final coat?
     
  10. Aug 12, 2019 #10

    rharshberger

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    Yep, brush it on, one thing that really helps is having a motorized rotisserie for tubes like a bigger version of whats used for fishing rods, that way the epoxy coat stays even. When priming use a filler primer, and sand before priming to lessen the amount to be filled.
    Im getting better at the naked FG/Carbon look but still not quite where I want to be, so lots of stuff gets painted.
     
    Last edited: Aug 12, 2019
  11. Aug 23, 2019 #11

    Nytrunner

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    Does a release film (perforated or not) help get a smoother finish?
     
  12. Aug 23, 2019 #12

    OKTurbo

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    Yes. A release film will give a smoother finish than a woven peel ply. Peel ply is a woven cloth that the extra resin can flow thru easily. Release film are plastic films...either smooth or perforated.

    If I want a smooth, shiny finish, I use mylar film for my first layer on top of the reinforcement fabric. When doing it this way you have to be careful not to use too much resin. It actually takes very little. I use the "John Coker" method and wet out the cloth before putting it on the part.
     
  13. Aug 23, 2019 #13

    G_T

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    That promotes air bubbles trapped in the layup.

    You want to wet out the fin, apply DRY fabric to the fin, roll the dry fabric to pull epoxy through the fabric, add a little more and roll out to uniformly damp, apply next layer of DRY fabric, repeat... That way you are resin infusing the fabric from a wet source to dry fabric, without ever capturing air in a damp pocket. This approach also makes it far easier to get proper fiber to resin ratio.

    I think it wasn't all that long ago I made a long series of posts related to this.

    Gerald
     
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  14. Aug 23, 2019 #14

    Nytrunner

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    You did! It was very informative
     
  15. Aug 23, 2019 #15

    G_T

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    Last edited by a moderator: Aug 23, 2019
  16. Aug 23, 2019 #16

    timbucktoo

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    I can do that & pin it in top of this forum.
    Gerald's posts have been moved here
     
    Last edited: Aug 23, 2019

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