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  • How long must paint dry before rubbing out?

    I'm still smelling some paint smells on these cabinets...



    I put the last coats on them several days ago and they still smell a bit. Do I need to wait until the smell dissipates before wet sanding and polishing? It only smells now if I get withing 4-5 feet or so.

    I used Krylon ColorMaster acrylic crystal clear gloss paint by the way. It went on really nice and looks beautiful in person. It's not extra thick looking, just like you put maybe 7-8 coats of rub on poly on it
    I applied probably 6-7 coats or so, then put on 4-5 more coats a day or two later. I put it on a smidge thicker than I should have, it looks like it started to 'droop' in two places.
    Not exactly a drip, but just a bit thicker there, like a sheet of it slid a little bit. I don't care, they came out really nice and I don't think I'll have trouble getting these super-shiny once I start polishing them.

    Interesting, on the can, it says recoat in 1 minute, dries in 10 minutes, Recoat anytime. Most stuff you need to do it within an hour or wait a day, not this stuff... just because it's clear as opposed to color? Anyway, It's good stuff and I'll certainly use it again, at $3.50 or so a can, it was a bargain.

    So do I need to wait for the stink to pass before messing with it, or can I have a go sooner?

    Thanks,
    Tomz
    Zarbo Audio Projects Youtube Channel: https://www.youtube.com/channel/UCEZ...aFQSTl6NdOwgxQ * 320-641 Amp Review Youtube: https://youtu.be/ugjfcI5p6m0 *Veneering curves, seams, using heat-lock iron on method *Trimming veneer & tips *Curved Sides glue-up video
    *Part 2 *Gluing multiple curved laminations of HDF

  • #2
    Re: How long must paint dry before rubbing out?

    3x as long as the mfr says. You are right to do the sniffer test, but there is also the fingernail test - if you can leave a dent with your fingernail, you will wreck it with a polish job.
    Don't listen to me - I have not sold any $150,000 speakers.

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    • #3
      Re: How long must paint dry before rubbing out?

      According to my daughter, who works in the paint industry, for almost any paint to fully "cure" it takes about 25 to 30 days(depending on temp/humidity) from application date.

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      • #4
        Re: How long must paint dry before rubbing out?

        Originally posted by CokewithLime View Post
        According to my daughter, who works in the paint industry, for almost any paint to fully "cure" it takes about 25 to 30 days(depending on temp/humidity) from application date.
        this is correct. if you can put them near a moderate heat source it will speed things up. I purchased a couple of aluminum reflectors that you use for plants for small projects. a couple of 100 watt bulbs and you can cut your wait time in half.
        craigk

        " Voicing is often the term used for band aids to cover for initial design/planning errors " - Pallas

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        • #5
          Re: How long must paint dry before rubbing out?

          You can rub it out while waiting for the paint to dry.

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          • #6
            Re: How long must paint dry before rubbing out?

            Get your advice here but I'd also call Krylon and ask the apps people.
            Also ask them what type of Acrylic it is.
            You should not have to wait a month if it is like automotive Acrylic,
            still I'd probably wait double what they tell you, and certainly if you
            have those very thick spots wait extra and use gentle heat or as
            much as the apps people tell you is safe.

            Toluene and Acetone, those are pretty powerful and volatile solvents:
            http://www.paintdocs.com/docs/webPDF...C=724504013013

            Can you explain how you got that look, are you just talking about the
            top clear coat as far as drying goes?

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            • #7
              Re: How long must paint dry before rubbing out?

              Wait.
              30 days is usually good. The parts that sagged could take longer.
              Give them plenty of fresh air, use a fan if needed. Warmer is better but good airflow is more important than temperature for most evaporative finishes.

              You can level off the sags a little tomorrow with a single edge razor blade. Scrape with the blade held almost perpendicular to the surface, leaning slightly forward as you scrape. Just hit the tops of the high spots. Stop at the first hint of pulling or crumbling. Repeat the next day if needed.

              The reason you can recoat anytime is the finish is an evaporative finish, a lacquer. The solvents will melt or dissolve existing dry finish and create a near perfect bond between coats.
              Enamels and varnishes, which are generally reactive finishes, do not meld between coats once the finish has begun to polymerize or harden. The solvents used have little or no effect on the dry film.
              Same holds for any of the catalyzed finishes (they are even more critical to recoat times).
              ~99%
              Make me an angel that flies from Montgomery
              Make me a poster of an old rodeo
              Just give me one thing that I can hold on to
              To believe in this livin' is just a hard way to go

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              • #8
                Re: How long must paint dry before rubbing out?

                I know lacquers take forever... Even after a month, the paint would peel off in chunks rather than sand finely... You can test in a small spot and see what happens, but if you still can smell the paint, it is still releasing solvents which means it has not cured. Patience is a virtue, painting is a work always in progress...

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                • #9
                  Re: How long must paint dry before rubbing out?

                  How long did you wait between each of the first 6 or 7 coats? Without proper 'flash' between coats, you may trap un-evaporated solvents under your new coat, which will slow down your dry time significantly. If the coats went on heavy and quickly, I agree with the others in that you should wait a few weeks before doing anything.

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                  • #10
                    Re: How long must paint dry before rubbing out?

                    I agree with the add heat recommendations. I work with a multitude of chemicals that can take from several hours to several days to cure at ambient temperatures, but pretty much all of them only need an hour when heated up to around 150 degrees.
                    http://jaysspeakerpage.weebly.com/

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                    • #11
                      Re: How long must paint dry before rubbing out?

                      Originally posted by Jay1 View Post
                      I agree with the add heat recommendations. I work with a multitude of chemicals that can take from several hours to several days to cure at ambient temperatures, but pretty much all of them only need an hour when heated up to around 150 degrees.
                      right, when something cures it is a chemical process, heat almost always speeds it up.
                      craigk

                      " Voicing is often the term used for band aids to cover for initial design/planning errors " - Pallas

                      Comment


                      • #12
                        Re: How long must paint dry before rubbing out?

                        True for reactive finishes, not so for this evaporative lacquer.
                        There is no appreciable catalytic reaction taking place no polymerization, just evaporation.
                        Nitro laquers and those acrylics formulated with alkyd resin/oils will benefit more since there is some polymerization and oxidation going on.

                        I'd also suggest caution subjecting a wood substrate, especially a veneered one, to extreme temperatures.


                        Originally posted by craigk View Post
                        right, when something cures it is a chemical process, heat almost always speeds it up.
                        ~99%
                        Make me an angel that flies from Montgomery
                        Make me a poster of an old rodeo
                        Just give me one thing that I can hold on to
                        To believe in this livin' is just a hard way to go

                        Comment


                        • #13
                          Re: How long must paint dry before rubbing out?

                          Originally posted by bobbarkto View Post
                          True for reactive finishes, not so for this evaporative lacquer.
                          There is no appreciable catalytic reaction taking place no polymerization, just evaporation.
                          Nitro laquers and those acrylics formulated with alkyd resin/oils will benefit more since there is some polymerization and oxidation going on.

                          I'd also suggest caution subjecting a wood substrate, especially a veneered one, to extreme temperatures.
                          So what is leaving the lacquer when it is "evaporating" to make it cure ? all lacquers are composed of resins and solvents, in water based lacquer the main solvent being water. for resins to be compatible with water you need an emulsion, in which water is essentially the carrier. the chemicals used to create the emulsions called surfactants. the main emulsion in water based lacquers is glycol ether, which is compatible both with water and the resins. The water evaporates after application, leaving the resin and solvent (glycol) to cure on the surface. Once the glycol evaporates, the resin droplets form a smooth, hard finish. the glycol evaporates due to breaking of oxygen bonds with the resin, a chemical process that heat will greatly enhance the speed of. so in reality it is still all about chemical reactions and heat.
                          craigk

                          " Voicing is often the term used for band aids to cover for initial design/planning errors " - Pallas

                          Comment


                          • #14
                            Re: How long must paint dry before rubbing out?

                            The solvents.
                            It's not curing, it's drying.
                            There is practically no polymerization or oxidation, hence no heat generation. No heat generation, no heat needed to cure, or more correctly, dry. There is no glycol or oxygen bond to break since the mix is not an emulsion.

                            The water emulsions are a different animal and behave as you describe, they're a combination of reactive and evaporative processes and reactions. Note that the products sold all require a minimum application temperature.

                            Purely evaporative finishes have no temperature requirements other than practical ones.

                            Originally posted by craigk View Post
                            So what is leaving the lacquer when it is "evaporating" to make it cure ? all lacquers are composed of resins and solvents, in water based lacquer the main solvent being water. for resins to be compatible with water you need an emulsion, in which water is essentially the carrier. the chemicals used to create the emulsions called surfactants. the main emulsion in water based lacquers is glycol ether, which is compatible both with water and the resins. The water evaporates after application, leaving the resin and solvent (glycol) to cure on the surface. Once the glycol evaporates, the resin droplets form a smooth, hard finish. the glycol evaporates due to breaking of oxygen bonds with the resin, a chemical process that heat will greatly enhance the speed of. so in reality it is still all about chemical reactions and heat.
                            ~99%
                            Make me an angel that flies from Montgomery
                            Make me a poster of an old rodeo
                            Just give me one thing that I can hold on to
                            To believe in this livin' is just a hard way to go

                            Comment


                            • #15
                              Re: How long must paint dry before rubbing out?

                              Tom - was this the first time you've tried a clearcoat of veneer?

                              I don't remember seeing that approach before and I'm curious if it's common and the pros/cons in relation to a more traditional wood finish (shellac, poly, etc...)

                              What was the prepwork on the wood before painting?

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