A21-29 Posted June 14, 2015 Share Posted June 14, 2015 hey guys,a little help please, i primed the bottom half of my 1/35 leopard tank,let it sit for a week or two started to brush paint and this is the result. its like the grey primer is slightly mixing with the matt light olive.I am a little concerned about moving forward on this till i work out what is going on.the turret is also primed.the body is not,and on a test bit the paint went on well.? am i doing something wrong? or is it a simple matter of more coats needed.that was just one. any help appreciated. Quote Link to post Share on other sites
jfmajor60 Posted June 14, 2015 Share Posted June 14, 2015 What types of paints are you using? If the primer and color coat are both solvent based paints then the color coat is reactivating the primer and mixing with it. Spraying it on wouldn't be a problem but with a brush it will be unless you seal the primer with Future or some other acrylic based sealer, or find the color you want in an acrylic paint. Quote Link to post Share on other sites
A21-29 Posted June 14, 2015 Author Share Posted June 14, 2015 the primer is british paints grey primer enamel spray can.the green in the pic is humbrol matt light olive,also enamel.i also tried tamiya nato green acrylic but was only just better after one coat. Quote Link to post Share on other sites
Triarius Posted June 14, 2015 Share Posted June 14, 2015 If the primer is a true enamel and is fully cured, this should not happen unless you are thinning the green with a strong solvent. Another possibility is that the primer was applied too dry and the brush is lifting microscopic particles of cured paint. It is also possible that the primer is actually a lacquer, and therefore only dries and doesn't cure like an enamel or an acrylic. With VOC requirements being what they are (and in a state of flux) it can be very difficult to tell whether what you are buying is an enamel, lacquer, or whatever, since these terms are used differently by the technical and sales departments. "Enamel" is used by the sales people for any coating they want to portray as a hard, strong material—like an enameled pot, which is coated by a ceramic finish. That is how the term originated. Over time, it became a shorthand for a curing coating, even among those who generally know better and understand the technically correct terminology. Obviously, the sales people and the tech people don't speak the same language. So here's how to tell, unless the coating is acrylic, most of the time: After the "enamel" has cured (~48 hours), brush it with its solvent. A lacquer will instantly dissolve. A coating that cures may soften, even dissolve, but the effect will be slower, and you are more likely to have it come off in clumps and sheets. This won't work with many acrylics, especially those that use a high proportion of alcohol in their solvent blend. Note also that "lacquer thinner" is made to dissolve almost everything. If you don't know what solvent to try on an "enamel," use mineral spirits (Stoddards solvent, NOT white spirit!) Most curing coatings are only slowly affected by mineral spirits. Quote Link to post Share on other sites
balls47 Posted June 17, 2015 Share Posted June 17, 2015 A21-29, I prime models more than I used to. I have never brush painted over a primed surface. I always spray over primed surfaces. I guess that I am just curious about this. If something can be done, I like to know that it can be done. We never know when we may have to try something that we have never done before. Have you ever brush-painted over a primed surface before, or is this your first try? I can see brush strokes on your area in question. I'm not beating you up by any means. After reading Triarius' post, I can see that it can be done. Quote Link to post Share on other sites
waterman Posted June 17, 2015 Share Posted June 17, 2015 the primer is british paints grey primer enamel spray can.the green in the pic is humbrol matt light olive,also enamel.i also tried tamiya nato green acrylic but was only just better after one coat. By any chance, are you using Humbrol 30? That olive color looks exactly like the color I used on a plane. Another possibility is that olive could be a bad batch of paint. I had a similar experience using Humbrol 30, except I was airbrushing it. No matter how much I sprayed, I could not get the color to lay down in a uniform coat. I kept getting a streakyy/blotchy appearance. As soon as the paint hit the surface, it would appear as a lighter shade (exactly like the brush strokes in your photo)...it was like I was spraying a solvent. When I mentioned my experience on another forum, I heard Humbrol was having quality control issues. For that reason, one of the guys said he doesn't use Humbrol anymore. To hide the blotchy appearance, I ended up weathering the entire aircraft. Quote Link to post Share on other sites
A21-29 Posted June 19, 2015 Author Share Posted June 19, 2015 (edited) it was humbrol matt 86,not using it now,went with tamiy xf67,nato green. i should add that i had the same issues with humbrol matt 84 on the primed part.had to do 4/5 coats and its still not that good.on the un primed surface there are no issues so i wont be priming the main body . Edited June 19, 2015 by A21-29 Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.