painting VE over Poly to seal inside tank?

Discussion in 'Materials' started by Jgfmobile, Mar 31, 2021.

  1. Jgfmobile
    Joined: Mar 2021
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    Location: Florida

    Jgfmobile Junior Member

    I took on a creative waste tank design, and have glassed it in-place inside my RV/box truck conversion.

    It is solid: i have kicked it, hammered it, sanded it like crazy, wiped it with acetone a few times, and i have run my razor inside of every portion of it.

    So far its made of poly and matte only; some of it being waxed, some not. (I know its NOT ideal, im learning). I plan on spraying acetone over the whole deal, saturating the surface then directly painting over the acetone-wet surface with my Vinyl-ester.

    NOW the question ive got is: since the tank is already "solid", do i have to add matte again, or can i simply coat the entire surface a few times with just VE? I have heard that VE can do its water block thing with about 10 mil thickness,which i can easily achieve with a few coats, right?

    I do plan on going over all this with Interlux 2000 also .... im figuring that since i used laminating VE, i will let it cure a day or two, then use my propane heater on it for a day or so (should get 100 degrees, as im in Florida) and then i will fill the tank with water for a couple weeks, to definitely cure the VE, and also test the tank.

    WHAT DO YOU THINK ?? ANY SUGGESTIONS !!???

    Thanks!!
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    You mean the outside of the tank, not the inside ?
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    If it is inside, and that is what the title says, try looking into phenolic-novolac epoxy tank lining coatings. I guess it depends what the tank will be holding.
     
  4. Jgfmobile
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    Jgfmobile Junior Member

    Its inside. I have these supplies already. The outside is 2 walls, a vanity back, and 3/4 plywood. This is inside my living space.
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    10 mil ? 10mm ? That is a lot. What is going into this tank ?
     
  6. Jgfmobile
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    Jgfmobile Junior Member

    10 mil. Thats 160 sq ft coverage from 1 gallon.

    Its sewage, this is a black/grey tank.
     
  7. Mr Efficiency
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    Mr Efficiency Senior Member

    Is the inside tack-free ? That would be what you would expect with waxed resin, that is is a possible snag.
     
  8. Jgfmobile
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    Jgfmobile Junior Member

    Yes it is tack free by now
     
  9. Mr Efficiency
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    Mr Efficiency Senior Member

    Probably best to consult member "Ondarvr" on this forum, what he doesn't know about resins probably isn't worth knowing. I am not sure that VE will take over polyester, even in well prepared.
     
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  10. Jgfmobile
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    Jgfmobile Junior Member

    It will. They are esters,they can mix. I suppose im just seeking validation on my ways here! Man this fiberglass thing can be a real challenge! Lol. Thanks for posting
     
  11. Mr Efficiency
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    Mr Efficiency Senior Member

    I know they mix up VE and polyester in lay-ups to avoid osmosis, but there would be no wax involved, that is the part that would concern me.
     
  12. ondarvr
    Joined: Dec 2005
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    ondarvr Senior Member

    You are over complicating this by a factor of 10.

    90%, well, 100% of your plan is wasted effort.

    You could use the container as it is now for the next 3 decades and it would be fine.

    Acetone will do nothing.

    Coating it with with VE would offer minimal benefits.

    The interlux 2000 will be worthless.

    Since you used waxed resin at times, you need to sand the entire surface before putting anything on it.

    A simple coat of the current resin with wax would probably be fine. VE would be better, but of little value for this type of tank. Anything more is a waste of time and money.

    And what does filling it with water have to do with helping it cure?

    I'm not trying to be mean, just stating it so others don't follow this plan as a good idea. There's a tremendous amount of poor advice out there on this kind of stuff, don't get sucked into it.
     
    Last edited: Apr 3, 2021
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  13. Jgfmobile
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    Jgfmobile Junior Member

    I was thinking that the acetone spray down would ensure that any leftover wax would not cause an issue, possibly floating to the surface like it would in styrene.

    Of course i will rough it up and acetone wipe it the best i can, beforehand.

    I already have the VE and interlux 2000e. The waxed PE is Bondo brand.

    I figured the water would air inhibit the resin, no? i planned on using a week or two of time and some days of aiming my propane heater towards the tank walls, to cure it. I figured id fill it with water for testing, with the bonus of it curing the tank ... No?

    This tank is going to be wet all the time, in Florida heat. You don't think the VE and Interlux would be of advantage?

    I have nightmares about this tank leaking, Lol. It would ruin my whole truck.
     
  14. ondarvr
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    ondarvr Senior Member

    Leaking would have nothing to do with VE or 2000. If it leaks its because there are defects in the laminate. How thick is the laminate?

    VE or 2000 won't make it more waterproof as far as leaks are concerned.

    Since you have the VE, use that with wax for a final coat, you don't need 10 mils, just one application.

    You need to sand the current surface, not just to remove the wax, but you need to scuff up the thoroughly cured surface the wax created.

    The 2000 adds nothing, save it for something that actually needs it.

    You don't need to blast it with heat, so forget that part. Water testing is good, but it does nothing to help cure the resin.
     
    Last edited: Apr 4, 2021
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  15. Mr Efficiency
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    Mr Efficiency Senior Member

    The structural integrity of the tank does seem the more important consideration, seeing any rupture will turn into an "international incident".
     
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