Electric Peel Ply!

Discussion in 'Materials' started by CatBuilder, Oct 14, 2011.

  1. CatBuilder

    CatBuilder Previous Member

    I was amazed today when pulling some peel ply and saw a huge blue arc (electricity) between the peel ply and the epoxy.

    It wasn't quite light out yet and every long piece of peel ply I pulled had a huge arc of electricity right at the line where it is just leaving the epoxy surface. The blue arc happened every single time.

    Anybody ever notice this before??

    I had read somewhere that epoxy bonded 3 ways: Mechanical (key), "some other way I am not recalling" and ionically.

    Are we tearing just the ionic bond when we pull the peel ply off?

    It was very interesting.
     
  2. waikikin
    Joined: Jan 2006
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    waikikin Senior Member

    I think its some kind of static phenomenon, I've noticed a blue dancing arc around the footprint of a grinder when used on the inside(lower light) of an epoxy/glass cat about 15 years ago, also the vacuum cleaner would happily give you a belt on the same job. Another issue I had once- I "cleverly" hung a tris' main hull from chain blocks via synthetic slings for a topsides respray, I could easily tilt the hull for easy access down each side, shot the hull & looked great but then I think every speck of dust in the shop became attracted to & stuck to the gleaming white finish- resulting in a re-sand & shot it again, this time with the sub waterline area grounded to the floor with damp toweling draped over some milk crates & cushions.

    May be the cats generate an ethereal & cosmic energy 'cos they're close to perfection:D

    All the best from Jeff.
     
  3. AndrewK
    Joined: Mar 2007
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    AndrewK Senior Member

    On low humidity day (rare here) the static build up is very high.
     
  4. Herman
    Joined: Oct 2004
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    Herman Senior Member

    Try demoulding a boat hull, (without water) then grap both the boat and the mould. Good for the hairstyle!
     
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  5. JRD
    Joined: May 2010
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    JRD Senior Member

    Hey Cat, This is a common occurence in industrial equipment, particularly where powder or dust is conveyed over non conductive surfaces. The higher the velocity the higher the charge. What you saw sounds similar to a phenomenon called "brush static" It has a relatively low energy level but has been known to cause combustable dusts, gasses or vapours to explode with catastrophic results.
    Not trying to suggest you are about to go up in smoke, but Id keep acetone well away from any source of static.
     
  6. susho
    Joined: Dec 2006
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    susho Composite builder

    Not only boat hulls Herman, I've got some carparts wich shock me every time, especially wet lay-up with epoxy.

    I was pulling some peelply out of a boathull(50 feet) once with a colleague when I saw the blue light. We turned out the light and had a lightshow :D
     
  7. Alan.M
    Joined: Sep 2005
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    Alan.M Junior Member

    First time I saw this I had just cleaned up some excess resin in one of my seat bases, then decided to remove old peelply to do some more glassing. The whole place was reeking of acetone, and I started peeling off the peelply - nearly **** myself!
     
  8. hoytedow
    Joined: Sep 2009
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    hoytedow Wood Butcher

    Just because we are in Florida doesn't mean we always have high humidity. In the winter I get shocked all the time getting out of vehicles or drying laundry. Always make sure there are no fumes present when peeling ply or removing synthetics from the dryer (Ours is in the garage).
     

  9. Niklas
    Joined: Nov 2018
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    Niklas New Member

    Old thread but physics never gets old! I managed to capture it on video during a peelply session on my latest kayak build.



    /Niklas
     
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