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Hot-coating bottom paint

Discussion in 'Chris Craft Roamer Yacht' started by q240z, Jul 22, 2009.

  1. q240z

    q240z New Member

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    Anybody have any experience hot-coating bottom paint? I'm going with Vivid on my Roamer and will be putting on the last coat of Devoe 235 barrier epoxy this weekend followed immediately by the bottom paint. Pettit says the paint is formulated for this no-sand approach, but they warn against allowing the primer to kick too far before laying on the bottom paint. I figure I'll do one half of the hull in primer, then do the same side with paint. They also say there's no maximum recoat window so long as you ensure the surface is clean.

    Thoughts?
  2. q240z

    q240z New Member

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    Are those crickets I hear chirping?

    lol
  3. NYCAP123

    NYCAP123 Senior Member

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    OK, I'll admit being ignorant. What is Hot-coating bottom paint? Maybe I know it by another term.
  4. acellist

    acellist Member

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  5. q240z

    q240z New Member

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    As I understand it, it's "putting on the last coat of...barrier epoxy...followed immediately by the bottom paint." In other words, while the epoxy is still tacky you're rolling on the Vivid. Acellist's links cover it well.

    Hopefully, I'll confirm in ten years or so that it works. lol
    Tugman likes this.
  6. NYCAP123

    NYCAP123 Senior Member

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    Thanks for the education. After reading that I realized there was a Forum discussion on that in another thread a while back. It sounds like a lot of work, but hopefully it will never be me doing the work. I'd guess the cost would be about triple a regular paint job which means it has to last about 5 years with no further painting to pay for itself. Does that sound about right?
  7. Capt J

    Capt J Senior Member

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    When the yards down here do an epoxy barrier coating, they usually let it sit for two days, then sand the epoxy coating and then put the bottom paint from what I have seen. They usually use interprotect from what I've seen. I've never heard of hot coating it.....
  8. q240z

    q240z New Member

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    It's actually less work than if you do what Capt J says the yards in his area do because you skip that last round of sanding. But this isn't something you'd do on a regular maintenance-type haul and bottom paint schedule. I'm doing it as part of bringing an old Roamer back from the dead, including sandblasting the hull to white metal and applying a modern epoxy barrier coat. I'm just sick of sanding this big ol' hull, so I was happy to hear about hot coating from the Pettit guru.
  9. NYCAP123

    NYCAP123 Senior Member

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    That, a virgin bottom or one that was pealed or a trailered go-fast sound like the perfect candidates for this.
  10. Seafarer

    Seafarer Senior Member

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    OK, I'll bite.

    Why would it cost more and/or be more work than letting the epoxy or barrier coat dry, then prepping that for the first coat of bottom paint? It seems like it would take less time and less work.
  11. Seafarer

    Seafarer Senior Member

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    A trailered go-fast wouldn't get bottom paint. Bottom paint increases drag and weight thereby decreasing speed.
  12. NYCAP123

    NYCAP123 Senior Member

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    If I remember the thread correctly they were stopping at the barrier coat on the go-fasts. No bottom paint.
    When I guessed the cost to be triple a conventional paint job I wasn't just referring to the prep.
  13. Capt J

    Capt J Senior Member

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    The bottom would have to be completely stripped in order to put an epoxy barrier coat.

    It would be cheaper to hot coat it. Meaning if you apply the last coat of epoxy barrier coat and then the 1st coat of bottom paint before the epoxy dries.

    If you let the epoxy dry, you then have to sand it before applying bottom paint therefore creating the extra work.
  14. Seafarer

    Seafarer Senior Member

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    I'm still confused as to how putting paint onto other paint (essentially) while the first is still tacky makes it more expensive.

    Go-fasts usually don't put barrier or anything else as a coat, they try to stay as close to gelcoat or a slick surface as possible. Especially trailer-kept boats, which get bottom washed pretty much after every use. What's to barricade during the few hours the boat is splashed?
  15. Minnow

    Minnow New Member

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    Q240Z

    Hot coating bottom paint works well, if you are using an ablative paint a nice trick is to hot coat a bottom paint in a color which contrasts that of the top coat bottom paint color and then continue in your regular color (i.e. If your bottom paint is black, hotcoat in blue) of course check manufacturers compatibility of all coatings. This will be great indicator of wear, impact damage and poor adhesion. After 9,000 or 10,000 miles (at 20kts.) the stem and leading edge of the stabilizers turn blue and any impact damage is evident as the soft bottom paint is the first to be scraped off revealing the contrasting color beneath. Also real handy if someone is sanding the bottom as when they start to see the contrasting color they will stop BEFORE damaging the barrier coat. Best of luck
  16. q240z

    q240z New Member

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    Thanks, Minnow. Hot coating appears to have worked well. I'm tossing on another 1.5 coats tomorrow, then calling the bottom done for this round.

    Some advice I heard and decided to follow was to go with hard bottom paint, like Vivid, for the first round, then do subsequent bi-annual maintenance coats in ablative. Of course, that will mean having to lightly sand the Vivid once in a year or two, but then you avoid having to do it again by running with paint that basically is designed to fall off over time. We'll use the two-color approach for the ablative paint, which should preserve the barrier coat nicely.