Customs: Polyurethane vs. epoxy

Discussion in 'Creative General Discussion' started by Fishdirt, Dec 3, 2010.

  1. Fishdirt

    Fishdirt Tin Toy Transformer

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    So here's the situation. I have no dough for more polyurethane casting and I'm being asked to sell castings. I have a couple good ones but my casting supply is running out. Without a pressure chamber I'm making heads with one or two small divots. I have clear epoxy resin I bought a while back and just started casting (slow cure time so I am not sure how they turn out but I am feeling good that the air issue will be better because of the slow cure).

    My question is, which is better as far as strength and appearance? I have this feeling epoxy may be really nice but I notice most casters use polyurethane or the polyester from alumilite. Is there a reason why no one really uses expoxy resin?
     
  2. Bigbot3030

    Bigbot3030 Well-Known Member

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    While there are many types of both kinds, I have found epoxy to be harder, but more brittle. It doens't "give" as much as urethanes do.

    Randy!
     
  3. Fishdirt

    Fishdirt Tin Toy Transformer

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    weird. I always thought of it as softer in the sense of products they sell being encased in it. It felt strong but with a weird soft type feel on the outside.

    I'll have to use it for specific things then.

     
  4. minsok

    minsok Well-Known Member

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    Seconded.
     
  5. Bigbot3030

    Bigbot3030 Well-Known Member

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    not sure what you mean by the above part. Specifics?

    Again, it's all about what kind you buy. there are some more expenisve epoxies out there that behave like urethane, but they are more expensive and hard to come by. sometimes they also only come in the giant tubes used more for commercial use.

    "It felt strong but with a weird soft type feel on the outside."
    That would worry me if I was trying to build something strong. I'd prefer it the other way around. :) 
    Sounds like you got a handle on it.

    Randy!