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  1. #11
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    Quote Originally Posted by LBCrew View Post
    After the patches are down and cured, and you've faired out the edges to make them smooth, you take a little resin and paint the area. It's called a hot coat because you can make it "hot" with a little more catalyst so it goes off quicker. Once your hot coat is hard, sand it smooth and call it done. To help confine the hot coat resin to the patched area only, tape it off with masking tape.
    Got it, that makes sense. I will try it this weekend, thanks!

  2. #12
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    One more (dumb) question. I always thought you had to use the heat catalyst. I understand it increases the dry time exponentially, but do you really not have to use it? I always thought you had to.

  3. #13
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    Quote Originally Posted by stoneybaloney View Post
    One more (dumb) question. I always thought you had to use the heat catalyst. I understand it increases the dry time exponentially, but do you really not have to use it? I always thought you had to.
    You need the catalyst. Depending on the amount you add will determine the dry time. The more you add the faster it will harden. Now resin WILL technically harden all by itself. But it will take a loooong time. Like weeks. or longer.... I had a bottle of resin with a little left in it sitting around for a year. I couldn't get it opened so I cut a hole in it to try and get some out. The resin was like a solid rock. Test it out for yourself....grab a brush and paint on some resin without catalyst on something useless. You will see eventually it will harden. But it will take forever.

  4. #14
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    Quote Originally Posted by Aguaholic View Post
    You need the catalyst. Depending on the amount you add will determine the dry time. The more you add the faster it will harden. Now resin WILL technically harden all by itself. But it will take a loooong time. Like weeks. or longer.... I had a bottle of resin with a little left in it sitting around for a year. I couldn't get it opened so I cut a hole in it to try and get some out. The resin was like a solid rock. Test it out for yourself....grab a brush and paint on some resin without catalyst. You will see eventually it will harden. But it will take forever.
    Ok, so you can mess with the ratios then. I guess there is also such a thing as drying too fast. In my case, I'm looking for dry time of less than 24 hours.

  5. #15
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    Drying and curing are 2 different things.

    Drying can be done in a couple hours or less. Curing well..... takes weeks.

  6. #16
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    Quote Originally Posted by Aguaholic View Post
    Drying and curing are 2 different things.

    Drying can be done in a couple hours or less. Curing well..... takes weeks.
    What would curing be consider? The complete drying throughout the entire material?

  7. #17
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    Quote Originally Posted by stoneybaloney View Post
    What would curing be consider? The complete drying throughout the entire material?
    Yes........

  8. #18
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    A catalyst is a chemical that speeds up a reaction by creating a "short cut." Add more catalyst, and you get a faster reaction. You need catalyst for a proper cure when dealing with thermoset resins... which both polyester and epoxy resin systems are. "Thermoplastics" is another term you might hear. However, if you use too much catalyst, you will build up so much heat (exotherm - the heat generated by a chemical reaction) that you will alter the physical properties of the end product of the reaction. In the case of catalyst and polyester resin, you make the resin become brittle and change color. So... don't add too much catalyst! Ideally, you want a kick time of no more than 20 minutes. Even that's a long time. "Hot" batches should be much faster than that. Check the manufacturer's instructions on how much catalyst you can use, at what ambient temperature.