Best Epoxy for *Hand* Layup??

Discussion in 'Materials' started by CatBuilder, Nov 25, 2010.

  1. CatBuilder

    CatBuilder Previous Member

    I thought I had learned all about epoxy here once, but now I have new requirements. I am no longer bonding wood. I am doing hand layups, vertically. I'm bonding very heavy triaxial to Corecell foam.

    What epoxy would be best to do these hand layups of 34oz (1150gsm) triaxial?

    My conditions are: Florida, out doors!

    It seems to range from 50-100 deg F (10C-37.7C), with 50%-90% relative humidity.

    I need an epoxy system that will cover these temperature ranges and have no blush (humidity related).

    I also need an epoxy system that will allow me to completely wet out the 34oz (1150gsm) triaxial fabric on a *vertical* layup, by hand with rollers. I don't want the epoxy to be so thick that it can't wet out the triaxial, but I don't want it so thin that it just runs down the side of the hull.

    What would you suggest??? West System ProSet and Gurit Ampreg have been suggested so far.

    Suggestions? Ideas? Which do you use if you are in FL?
     
  2. War Whoop
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    War Whoop Senior Member

    SP Ampreg 22
     
  3. AndrewK
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    AndrewK Senior Member

    The only thing I dislike about ampreg 22 is the relatively low elongation.
    Previously you went through a thorough selection process and chose sytem 3, get a sample of all your cloths and see how easily they wet out with it.
     
  4. AndrewK
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    AndrewK Senior Member

    Also in your high humidity levels it is better to use peel ply as a means of dealing with blush rather than accepting manufacturers claim that their system is blush free.
     
  5. sabahcat
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    sabahcat Senior Member

    Personally, I prefer pulling a runny brew of epoxy/qcells over the finished job
    Cheaper and easier than peel ply
    and I'd rather sand bog than glass
     
  6. War Whoop
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    War Whoop Senior Member

    With epoxies a lot is relative to the hardener system and Post cure,I never had a blush problem either and use epoxies everyday repairing boats on the water in South Florida.SP used to make Awlfair for Akzo Nobel so I had a common source for lamination and Fairing material.
     
  7. CatBuilder

    CatBuilder Previous Member

    I should add that I can only achieve about a 100-110 Deg F post cure temperature. Ideally, I am hoping for a room temperature curing epoxy that doesn't need all the post curing.
     
  8. Submarine Tom

    Submarine Tom Previous Member

    You can also just use "regular" slow cure West System and thicken it with one of their many thickeners.

    -Tom
     
  9. AndrewK
    Joined: Mar 2007
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    AndrewK Senior Member


    I find that it takes about the same time for both approaches.
    Peel ply costs me $1.25sm and resin $12 - 16kg, even at say 200g of resin to make a brew to cover 1sm this turns out to be twice as expensive as peel ply.
     
  10. Landlubber
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    Landlubber Senior Member

    ..yeah Andrew, i seem to favour the peel ply for more reasons than the simple costs, there is also the semi finished surface that it creates, certainly makes any other work over it (as such), to be so much easier.
     
  11. Landlubber
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    Landlubber Senior Member

    ...also, take a sample of "real" peel ply to the local material shop, they regularly have products (polyester....dacron) that you can use. Spinaker cloth must be the same.

    Nylon tafeta is one choice I have seen used for epoxy.

    Try a sample piece before committing to a job. Ask Apex what he uses, i bet it is not the "real" thing....
     
  12. sabahcat
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    sabahcat Senior Member

    Strangely enough I have always found I had to add extra resin to make peel ply work
    But each to his own.
    I have to bog the boat anyway, so I may as well bog it as I go in my opinion.

    Another reason I went off peelply was an article posted in a magazine back in the 90's about a fairly major failure where peel ply was removed and glassed back into, and the join let go later.
    They discovered that peel ply has a silicone residue that was left in the surface, which compromised the bond.

    Further reading here http://www.google.com/search?source...peel ply silicone&btnG=Google Search&aq=f&oq=

    add: The nylon cloth sourced from material stores is suit lining
     
  13. AndrewK
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    AndrewK Senior Member

    I put up the cost comparison because the most often reason given by no peel ply proponents is the cost.
    I like it for many reasons too.
     
  14. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    No such thing in your working environment, so get over it and accept that you will have a blush. You can use peel ply, which is the expensive way or you can employ nylon "rip stop" which you can get at the local craft or fabric store for much less. There are also other techniques to mitigate blushing.

    This is more about technique then the resin system you select. You can use the expensive stuff if you want, but I see no need, particularly with the building conditions and techniques being employed on this project. Save yourself some money and use Marinepoxy. I also am not a Ampreg 22 fan and again considering your building environment and layup techniques, ProSet seems a waste of money too.

    I've developed a couple of proprietary mixtures from local formulators, but in all honesty, you can get by with just a standard and a slow from one a number of sources, with cost likely being the primary factor in selection, if only because you're so screwed in your working environment.
     

  15. waikikin
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    waikikin Senior Member

    Catbuilder, unrelated to brand, you will benifit from pre wetting your fabric, either use an fabric impregnator or just set up a "pre wetting" table- simply melamine faced chipboard covered with a few disposable layers of builders plastic- wet your fabric- then roll onto suitable lengths of pvc storm or sewer pipe & then unroll to apply to vert/overhead surface. All the best in your endeavours from Jeff.
     
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