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  • Spray painting advice

    Doing some spray painting at work this week. Now, I'm not a professional painter, but I can usually get some alright results. Problem I've got is the paint is 'orange peeling' and I don't know whats causing it. Have I set the gun up wrong? Wrong pressure? Wrong techinque? I don't know.

    Someone wanna explain how to get a nice finish on the job, please?
    A cynic is a man who, when he smells flowers, looks around for a coffin.

    Dear god, it's some weird bastardized three wheeled two person go-kart.

  • #2
    too cold what you are painting or where you are painting needs to be warmer

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    • #3
      That would explain it. I normally have to chase the penguins out of the hangar before I start work in the morning. So if was to pre-heat the job with some heat lamps, it should smooth out then?
      A cynic is a man who, when he smells flowers, looks around for a coffin.

      Dear god, it's some weird bastardized three wheeled two person go-kart.

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      • #4
        Maybe the penguins are leaving oil on the surface of the piece you're spraying?
        For LAMS information and resources - http://www.perthstreetbikes.com/foru...thread-156358/
        For LAMS discussion and to ask questions - http://www.perthstreetbikes.com/foru...thread-143289/

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        • #5
          No, its not fish-eyeing. The surfaces are sanded, tack-clothed and chemically cleaned before paint application.

          I thought that initially, but a water-bead test ruled that theory out.
          A cynic is a man who, when he smells flowers, looks around for a coffin.

          Dear god, it's some weird bastardized three wheeled two person go-kart.

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          • #6
            Is its 2pac or acrylic?

            Originally posted by t bone View Post
            too cold what you are painting or where you are painting needs to be warmer
            I'm not 100% sure for acrylic but i know for 2pac you have that the wrong way round. If its to cold the thinners takes longer to evaporate and this allows the paint to flow out flatter, but can also lead to runs and sags in the paint.
            Ideal spray temp is about 24-25deg plus the surface you are painting shouldnt be cold to touch. If its metal ur spraying and its real cold try warming the panel up a bit with a heat gun.

            As for excessive orange peel that can be caused by a few things. If its smooth looking orange peel then you could be applying ur paint to heavy then combined with a fast thinners or hardener the paint is curing before it has a chance to flow out flat.

            If its a course really fine lookin peel then this is usually refered to as being "dry". This can be caused by-
            *Ambient heat to high 30deg+
            *Gun is dirty and isnt atomising the paint in a even pattern
            *To much thinners causing to much thinners and not enough pigment to be sprayed
            *Not enough thinners causing paint to be really thick and the gun is not able to correctly atomise the paint.
            *Uneven overlapping, basically not applying enough paint. You should overlap ur last stroke by about 1/3
            *Check the breather hole in the pot, if air isnt getting in then paint is getting about so u end up spraying more air than paint on the surface.

            Probably a few more but thats about all i can think of at the mo, but at a guess i'd say dirty gun or blocked breather as u said u can usually get a nice finish so unless ur've changed ur technique its shouldnt be the application.
            B19 Oakford V.B.F.S

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            • #7
              Its a 2 pack polyurethane mixed 2:1 by volume paint to hardener as per manufacturers specs with 10% thinners by volume for spray gun application.

              The panels are usually quite cold to the touch and this is in 10 degree temps indoors, so the panels are probably near freezing. Humidity has to be below 75% before I start applying, but thats more for the application of the strontium chromate primer.

              I'll try warming the panels up under heat lamps tomorrow morning and see if that changes things.

              The gun I use is cleaned at the end of every day its used, plus between applications. All the jets, needles and breathers are clear and clean.

              Thanks for the help peeps. I'll let you know how it goes tomorrow.
              A cynic is a man who, when he smells flowers, looks around for a coffin.

              Dear god, it's some weird bastardized three wheeled two person go-kart.

              Comment


              • #8
                ewww polyurethane hate that stuff, the other painter at work usually does all the industrial stuff and uses poly-u to paint the Western Power cranes etc. Horrible stuff gunks up filters and stays sticky in the air for ages.

                Pol-u is a fairly thick material so mayb try thinning it down a bit more if ur chasing a flatter finish. Mayb 15% but now u have to be carefull and allow a longer flash of time between coats as there is a greater chance of getting a run specially with cold ambient temp.
                B19 Oakford V.B.F.S

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                • #9
                  Okay, I'll give that a go as well.

                  Yeah, poly is a bitch to work with, but its the only stuff that resists stripping when the aircraft flys through rain at 200 knots.
                  A cynic is a man who, when he smells flowers, looks around for a coffin.

                  Dear god, it's some weird bastardized three wheeled two person go-kart.

                  Comment


                  • #10
                    I painted one of them redbull stunt planes a couple years ago. Had to put flex addidtive in the paint so it wouldnt crack when the wings and body flexed as they were pullin the big G turns
                    B19 Oakford V.B.F.S

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                    • #11
                      Originally posted by MrMike View Post
                      I painted one of them redbull stunt planes a couple years ago. Had to put flex addidtive in the paint so it wouldnt crack when the wings and body flexed as they were pullin the big G turns
                      ha ha its insane what those red bull planes do . . . .i think i would think twice before jumpin in one . . . anyway just spoke to a mate of mine who is a painter and he said adjust your room temp if you can . . . . hope that helps bro ! i f*cken hate orange peel on shiny new panels hey
                      Keep being awesome ^_^

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                      • #12
                        Thread Hijack -
                        Whats the cheapest, simplest and quickest way to paint race fairings? Also is white the easiest colour to use? or is another colour better?
                        Supported and kept fit by sigpic

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                        • #13
                          sand em off with 420 or 600, get a paint gun and acrylic (easier to use) and spray them. Very quick and easy. This only works for prepainted fairings

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                          • #14
                            I would have thought white or black would be the easiest.

                            It's a huge difference though. I know that using paint-on acrylics, I'm completely hopeless with yellow and greens can be a little hard to get consistent. Transfer that to spraypainting, one coat of black over yellow covered better and with more consistency than 6 thin and 2 thick coats of yellow over grey -- I've never managed to get good, solid coverage from any brand of yellow, so it's not just a weakness in the paints I've been using, afaik.

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                            • #15
                              Gloss? White shows up runs, sags, thin patches etc etc one helluva lot less than black. Matte black is pretty forgiving of most mistakes. but looks shit.

                              Rattlecans, cheap arse white export from Supercheap will be by far the easiest and cheapest way of doing this if you don't have access to the gear.
                              "Once upon a time we would obey in public, but in private we would be cynical; today, we announce cynicism, but in private we obey."

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