How to tell if I got bad paint? Or thinner?

Discussion in 'Painting Questions, Tutorials and Guidebooks' started by RGaspar, Sep 29, 2013.

  1. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    Working on and eduard bf110e lately, and was finishing up the paintwork with RLM74 and my airbrush started sputtering and eventually no paint would come out, just tiny mists of thinner. Also, I noticed hundreds of chips had formed inside my iwata big mouth bottle when spraying my RLM 71 yesterday. I use model master paints, and I've recently been trying a new(cheaper) thinner called Klean Strip, it's kinda milky white and it's extremely low fumes and non flammable, which makes spraying in my basement more tolerable, less fumes in the house when I'm done. Anyway, can someone help out with some advice? FYI I use and iwata neo siphon feed brush with and iwata ninja jet compressor which has worked flawlessly up until this issue arose.
     
  2. Wurger

    Wurger Siggy Master
    Staff Member Administrator

    Joined:
    Jun 19, 2005
    Messages:
    47,801
    Likes Received:
    1,568
    Trophy Points:
    113
    Occupation:
    A retired military Navigator/ATC, FIS controller
    Location:
    Poland
    Are these ModelMaster colours the acrylic ones or enamels? And where did you buy the thinner?
     
  3. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    Enamel. Been using them since I was 8 . I got the thinner at Wal Mart. Starting to think it was a dumb idea, but maybe y'all can set me straight
     
  4. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    I bought the model at my local hobby shop for the heavy hitters GB, but a move into my first home kinda set things back just a wee bit lol still trying to decide what to build for the nose art GB, just can't make my mind up!
     
  5. Rogi

    Rogi Active Member

    Joined:
    Aug 1, 2011
    Messages:
    2,161
    Likes Received:
    12
    Trophy Points:
    38
    I usually just use the Brand your painting's thinner if I want to cheap out I use a generic thiner (theres a specific one for each type of paint) that is purchasable at hardware stores. I've never bought items like food or thinners from Walmart after I'd had their Future Floor Wax and Mars bars recal incidents.
     
  6. Wurger

    Wurger Siggy Master
    Staff Member Administrator

    Joined:
    Jun 19, 2005
    Messages:
    47,801
    Likes Received:
    1,568
    Trophy Points:
    113
    Occupation:
    A retired military Navigator/ATC, FIS controller
    Location:
    Poland
    It is possible the thinner isn't for enamels but for these acrylic paints judging by its milky white tinge. Are these chips of white as well?
     
  7. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    No just paint chips. It says on the bottle for enamels and that it won't change the color of the paint, which it hasn't done so far. Maybe the paint is bad because I dump the excess paint/thinner mixture back into the paint bottle when I'm finished? Hey, I hate to waste! I've only been using this airbrush for a short time, this is the first plane I've used an airbrush on, before that it was all paint brush work. il post pics up when I find my camera, and pics of my other warbirds as well
     
  8. Wurger

    Wurger Siggy Master
    Staff Member Administrator

    Joined:
    Jun 19, 2005
    Messages:
    47,801
    Likes Received:
    1,568
    Trophy Points:
    113
    Occupation:
    A retired military Navigator/ATC, FIS controller
    Location:
    Poland
    It is said that any thinner shouldn't be added to a basic can ( bottle ) with a colour. The process of thinning has to be run with a separate container where mixing can be done. So it might have been the reason. Anyway I would suggest giving up of the thinner. Again the rule what is cheap is no good, comes true.
     
  9. Airframes

    Airframes Benevolens Magister

    Joined:
    Aug 24, 2008
    Messages:
    47,730
    Likes Received:
    1,425
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Cheshire, UK
    That sounds like the problem! The unused paint in the bottle is being contaminated by the paint/thinner mix being poured back. The excess of thinner building up, is causing separation of the paint pigment, which in turn is clogging the air brush.
    For the price of a bottle of thinner, dump the remaining paint/thinner once used. It's cheaper in the long run, as air brushes cost far more than a bottle of thinners!
    With enamels, the use of any good quality enamel thinner, or 'White Spirit' (Turpentine substitute) is fine, but that thinner with a milky look sounds suspect to me! It should be clear, like water - or vodka!.
     
  10. Wurger

    Wurger Siggy Master
    Staff Member Administrator

    Joined:
    Jun 19, 2005
    Messages:
    47,801
    Likes Received:
    1,568
    Trophy Points:
    113
    Occupation:
    A retired military Navigator/ATC, FIS controller
    Location:
    Poland
    I agree with the post above entirely.
     
  11. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    Thanks for the help guys, much appreciated. I just figured pour it back, less thinning later lol well now to toss a couple $3.97 jars of paint and buy some high quality testors airbrush thinner
     
  12. mikewint

    mikewint Well-Known Member

    Joined:
    Feb 17, 2010
    Messages:
    5,690
    Likes Received:
    432
    Trophy Points:
    83
    Gender:
    Male
    Occupation:
    Retired and living on the dole
    Location:
    Lakeview, AR
    Total agreement with Terry, I use "Mineral Spirits" which you can get in gallon cans at any hardware or paint store. I then pour from that gallon can into smaller jars. Two to clean brushes and one to thin paint/clean airbrush.
     
  13. Airframes

    Airframes Benevolens Magister

    Joined:
    Aug 24, 2008
    Messages:
    47,730
    Likes Received:
    1,425
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Cheshire, UK
    Thanks Mike, I didn't know the American name, or term, used for what we call 'White Spirit', but it's almost certainly 'Mineral Spirits'.
    There is very little, if any, difference, between this and the thinners bearing a paint company label, such as Humbrol, Testors, Model Master etc etc. It may be that the 'branded' variety are slightly more refined, but unlikely. Given that the white/mineral spirit is used once for thinning, it should work exactly the same as the more expensive stuff. For brush cleaning, once it's showing obvious signs of contamination, dump it and use fresh.
    I have two cleaned-out yoghurt containers for brush cleaning - one for dipping to remove the bulk of the paint from a brush, the second, with clean thinners, for a final 'thinners rinse', then the brush(es) are wiped dry on a piece of kitchen towel, then washed in warm, soapy water and allowed to dry naturally.
    I get my thinners in a 5 liter /1 gallon container from the local DIY 'shed', and decant as required. It costs roughly the same for this size, as a branded 'modelling' thinners would cost for a small can or bottle !
     
  14. mikewint

    mikewint Well-Known Member

    Joined:
    Feb 17, 2010
    Messages:
    5,690
    Likes Received:
    432
    Trophy Points:
    83
    Gender:
    Male
    Occupation:
    Retired and living on the dole
    Location:
    Lakeview, AR
    Terry, yup be willing to bet it is the same stuff, in essence a synthetic turpentine
     
  15. Airframes

    Airframes Benevolens Magister

    Joined:
    Aug 24, 2008
    Messages:
    47,730
    Likes Received:
    1,425
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Cheshire, UK
    Yep. In the UK, it even has 'Turpentine Substitute' printed below the 'White Spirits' title.
    There are endless types of product, re-packaged as 'modelling' products, at relatively high prices, which are just day-to-day stuff. Some adhesives, especially 'clear' types, for making windows or attaching clear parts, polishes, sanding sticks etc etc, are all everyday products available at a very small fraction of the cost of 'modelling' products.
     
  16. RGaspar

    RGaspar Member

    Joined:
    Nov 24, 2011
    Messages:
    53
    Likes Received:
    2
    Trophy Points:
    8
    Occupation:
    Painter at Hawker Beechcraft
    Location:
    Kansas
    Thanks guys. Il make a trip to the hardware storenthis week and pick up a big can of mineral spirits. Dang it I can't find my camera anywhere! I'd love to show you guys some pics of my finished planes, a 109 g14, a 190a8-r2, a he111 h22, a spit mkII or III, can't remember and my current build, the eduard 110E. Man the eduard kit is pretty nice, surprising amount of little parts, but wow building the nose gun area was the biggest pain ever for me. :)
     
  17. stona

    stona Well-Known Member

    Joined:
    Mar 28, 2009
    Messages:
    7,537
    Likes Received:
    949
    Trophy Points:
    113
    It is, as you've probably guessed by now :)

    I'm currently using White Spirit from Wickes which doesn't even proclaim itself a turpentine substitute thought it does claim to be "ideal for paint thinning, brush cleaning and general degreasing" on the label!
    It's £7.00 for four litres which even my dodgy maths works out to be less than 50p a litre and it works fine with my Humbrol and White Ensign enamels. Four litres lasts a very long time!

    I never have and never will pour thinned paint back into the paint for reasons already mentioned. That is a recipe for disaster.

    I found that I wasted far less paint with a gravity feed airbrush too.

    Cheers

    Steve
     
  18. mikewint

    mikewint Well-Known Member

    Joined:
    Feb 17, 2010
    Messages:
    5,690
    Likes Received:
    432
    Trophy Points:
    83
    Gender:
    Male
    Occupation:
    Retired and living on the dole
    Location:
    Lakeview, AR
    All of the above is why I switched to using Acrylics for almost all my painting. I use only a very few enamals and only when I can't find what I want in an acrylic. Mostly water clean up or at most isopropyl alcohol (rubbing)
     
  19. Wurger

    Wurger Siggy Master
    Staff Member Administrator

    Joined:
    Jun 19, 2005
    Messages:
    47,801
    Likes Received:
    1,568
    Trophy Points:
    113
    Occupation:
    A retired military Navigator/ATC, FIS controller
    Location:
    Poland
    I think it doesn't matter if we use enamels or acrylic paints. Just don't let's use "inventions" we know nothing about and offered in supermarkets.
     
  20. stona

    stona Well-Known Member

    Joined:
    Mar 28, 2009
    Messages:
    7,537
    Likes Received:
    949
    Trophy Points:
    113
    #20 stona, Oct 1, 2013
    Last edited: Oct 1, 2013
    Each to their own, but I switched to acrylics for a couple of years before reverting to enamels. My own experience is that enamels are far less likely to cause problems in the airbrush, brush paint much better than most acrylics and are much more tolerant of my approximate thinning technique.

    I have the advantage of space at the back of my house where neither I nor any smells interfere with anyone else and a terrific spray booth/extractor which shifts 335 litres of air a minute to the outside. I appreciate that not everyone can be so fortunate and that the smells which are associated with enamel paints can be a problem.

    I'll be using them until they ban them! I expect some overpaid and underworked eurocrat is working on that as I type :)

    Many, many acrylic users tell me that the safest way to thin acrylic paints is with their branded thinners. You definitely don't need to do this with the enamels that I use.

    Of course there is another possibility, that I'm just an old fart who can't or won't learn new tricks!

    Cheers

    Steve
     
Loading...

Share This Page