Airless sprayer application of emulsion on new plasterwork

Discussion in 'Decorating and Painting' started by aspley, 6 Aug 2019.

  1. aspley

    aspley

    Joined:
    2 Jun 2005
    Messages:
    346
    Thanks Received:
    1
    Location:
    West Midlands
    Country:
    United Kingdom
    hi Guys, have just invested £1000 on a Q-tech spray gun. I’m a builder and thought it might be a good investment for spray painting new builds with my own lads who are skilled but not in painting (they are also quick learners:().
    A few questions I would appreciate some comment on are:-
    1...it’s all new plasterwork so would you advise mist coat @ say50% followed by either one or two top coats.
    2...the walls and ceilings will be white so is a Leyland super latex the best bet or should I use a Leyland contract paint. I always think contract paints seem a cheap and inferior alternative. But don’t really know what a ‘latex’ paint is.
    Thanks for any help
     
  2. Sponsored Links
  3. Notch7

    Notch7

    Joined:
    15 Sep 2017
    Messages:
    26,178
    Thanks Received:
    1,830
    Location:
    S. Uplands
    Country:
    United Kingdom
    Latex is more of American term.....its waterbased paint, not sure theres any diff from emulsion.

    Your Q tech airless gun will be powerful enough to spray emulsion straight from the tin, but you would be best to thin the first coat quite a bit as a mist coat. I expect you will need to keep the gun a bit further from the work and float a light coat on as a mist coat may run otherwise.

    Subsequent coats may need a little thinning to avoid orange peel.

    When you set the gun up, once its primed do some spray outs on some offcuts to get a feel. What you will find is that at low pressures the edges of the spray pattern will have a 'tail' which creates a line. Increase pressure until those tails disappear because the pressure has atomised them.

    You will find thinner paint can be sprayed at lower pressure -so for mist coats always adjust to suit.

    Tips for spraying:
    Fan pattern should be a nice oval. If its 'S' shaped the tip is blocked.

    If you cant get rid of tails -the tip could be blocked.

    Keep your paint really clean, dont let dry bits or build up from the tin lid to fall in the paint. You will get blocking tips.

    Clean main filter and gun filter often, they get clogged quite quickly.

    Have a few clean buckets for cleaning.

    Take tip off, put tube in bucket of water, pump paint in line back into paint tin.
    Then when it starts to run watery, sparay into a bucket.
    When it runs clear after 1 or 2 bucjets of water, put spray tip back on, increase pressure back upto spraying pressure and run some clean water through tip.
    You will find doing this leaves tips pretty clean.

    Some gun cleaner thinners is good to have for cleaning spray cap etc.

    I have lots of experience with air assisted airless, your gun has no air but the system is pretty similar.

    They are powerful systems which can push out a lot of material.

    There are some pro American decorating sites that discuss spray painting walls. From memory quite a few of them recommended using a roller after spraying to get the right finish texture and eliminate spray stripes.
     
    • Thanks Thanks x 2
  4. aspley

    aspley

    Joined:
    2 Jun 2005
    Messages:
    346
    Thanks Received:
    1
    Location:
    West Midlands
    Country:
    United Kingdom
    That is so useful......thanks for your advice

    ...From your experience is it likely I’ll get away with a mist coat and one finish coat?
    ...when you say clean filters regularly do you mean after each session of spraying or during spraying .
    Cheers
     
  5. LondonLad21

    LondonLad21

    Joined:
    14 Aug 2018
    Messages:
    48
    Thanks Received:
    3
    Country:
    United Kingdom
    A latex paint is essentially a vinyl, hence it is a more wear resistant paint that will take a scrub. I am not sure that you want to be laying that on too quickly post plastering, and if an older house, the walls maybe better off left to breathe with a porous paint finish as opposed to painting it in plastic.

    For new plaster, I sprayed with HVLP a diluted super matt to start with for ceilings and walls. The finish was amazing, you need it dilute for two reasons, as once it's airborne, you loose water content, and when it hits, you want to see it sucked in to the surface, not lay in top.

    I did a light mist coat, then another, heavier, and worked a treat.

    I sprayed subsequent finishes, you will find that

    - Matt paint, fine, will be beautiful, won't reflect, won't see imperfections...I saw nothing of fan spray coverage markings (Fuji XT tip)
    - Plaster finish, if it's not good, it's gonna show....a roller is more forgiving, Airless puts on more material, so you may find it fills better than HVLP
    - You can use a Floaterol additive if you find you aren not getting a smooth lay on, just helps the paint flow nicely,

    You will need to mask everything, the overspray carries more than what you think. the painting takes minutes, the prep doesn't.

    You'll be wanting to spray everything
     
  6. opps

    opps

    Joined:
    16 Jun 2006
    Messages:
    5,399
    Thanks Received:
    880
    Location:
    London
    Country:
    United Kingdom

    Super Latex paint- I agree I think the word latex may in fact mean vinyl. I also suspect that the word Super just means "more vinyl than a contract paint but less than a regular emulsion". Personally I would only ever use the first two classes of paint on plaster that was still slightly damp- ie a "needs must" bodge. They are impossible to keep clean but have the advantage of allowing the damp plaster to breathe.

    50/50 mist coats- I do not understand why anyone thins paint that much. No manufacturer recommends thinning paints that much. I just follow the advice on the tin (admittedly I don't have an airless gun though).
     
  7. opps

    opps

    Joined:
    16 Jun 2006
    Messages:
    5,399
    Thanks Received:
    880
    Location:
    London
    Country:
    United Kingdom

    Which Fuji turbine do you have?

    My Fuji turbine predates the Q series (about 15 years old). From memory it was the only one that they made at the time. The gun was awful. In the summer I had to wear thick rubber gloves because the handle became too hot to hold. The 7.5m hose was a rigid plastic which only became pilable when hot. And worst of all, when you turned the turbine on the air from the gun blew dust all over the place.

    When the Q series was released I purchased its 7.5m rubber hose (which I connected to my existing 7.5m hose- giving me 15m), the whip hose and the new XT bleedless gun. On Fuji's advice I drilled a small hole in to the pipe that runs to the hose fitting- being a bleedless gun the pressure has to go somewhere when not spraying. In time I also purchased a remote control switch so that I could turn the turbine on and off given that I try to keep it in a different room (in part because it is sooo noisy and so that it doesn't suck in the over spray. The (now) 15m hose also helps to cool the air before it gets to the gun.

    Given that it was only a 3 stage and that I have drilled a release hole in to it I have never managed to successfully spray anything as thick as emulsion. It is pretty much used exclusively for acid cat paint (which works well)

    With your set up, how much floetrol do you need to add for the finish coats? Given how small the cups are, do you use their larger pressure pot as well? And how do you spray a ceiling without some kind of extension pole.

    Perhaps I need to upgrade to the newer models, however I may decide to buy an airless and keep the old Fuji just for acid cat given that it does what it is supposed to.

    My experience of spraying is limited to HVLP but my understanding is that whilst airless is much faster, HVLP provides a finer finish (albeit with caveats).
     
  8. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
  9. Sponsored Links
Loading...

Share This Page