I am new to airbrushing and can’t afford fancy modeler paints so I am using craft paints based on tips from other posters in other threads.
In order to try out some tecnhiques for painting brick I got a package of DPM modular walls. I airbrushed them either folk art “rusty red” or createx “red oxide” as a 50/50 mix with washer fluid. I then tried some methods of doing mortar settling on doing a mortar wash in createx “quaker grey” and removing the extra with a scrunge pad.
I have been having trouble doing the same thing on my test kit, Bruce’s Bakery. I used the same paints and the same wash technique… but the paint does not seem to adhere to the material as well as it did with the modular walls resulting in my peeling the paint back to the biege plastic rather then just lifting off the excess mortar color.
I was wondering if there was any difference in the materials dpm uses for the modular kits vs the regular kits that might cause me to have adhering problems?
I washed off most of the paint I had on before and am trying again with Bruce’s Bakery tonight. This time I am going to use some liquitex airbrush medium I got cheap on ebay rather then washer fluid in the hope it will hold better. I also have some liquitex red oxide I could try but its a little too bright.
I don’t know if DPM uses different material for different kits, but I would hazzard a guess that your problem doesn’t lie with the material used to cast the walls, but rather the residue left over from the casting process. Most manufacturers use some sort of mold release to ensure that the castings are easily removed from the mold. The residual mold release forms a barrier to the paint and will cause the problem you have discribed. The simple solution is to wash all the pieces of your kit in warm soapy water and air dry before they “go to paint”. This may or may not solve your problem - but it doesn’t cost anything to try!
That’s just one of the issues with water based paints. They stick well to itself, but not so well to the material being painted.
If I’m not mistaken, DPM kits are cast resin, while most kits are injection molded styrene. That may be an issue, as well as mold release on the castings.
I do not like water based paints, and refuse to use them for any modeling I do.
I do use a lot of spray can paints for my structures. I buy spray primers in various colors, from different manufacturers. The different manufacturers colors are different shades; ie gray Krylon primer is a different shade than gray Plastic-coat, etc. The downside to using spray bombs is the inability to custom mix colors. But the variety of colors is pretty good.
I did wash the kit before painting. Perhaps not well enough. Tonight I will give it another toothbrush scrub since I want to avoid getting the black paint on the inside wet.
I have avoided using spray can primer because I am concerned about losing N scale brick detail. Is this a valid concern?
I knew DPM kits were a resin based plastic… I wonder if the DPM modular walls are more of a styrene?
What I do is wash the parts with softscrub and a toothbrush. After they are dry, I prime them from a spray can. I usually use model paint for this because the pigments are finer. If you try a can of Krylon or something else, just don’t get a heavy coat on it when painting. Once the primer is dry for a couple of days, then paint it with your water based paints.
I also use Model-Flex paint, AND they recommend that household window cleaner with amonia be used for cleaning the airbrush. So that leads me to think that you may have a problem with using washer fluid to thin your paint. BUT, at the same time, I haven’t used washer fluid to clean or thin my paint, so I can’t say for sure if that is hindering things.
I was having the same problem with craft paint. I scrapped the windshield washer fluid idea. Some of it seems to have some kind of soap in it. Why would you mix paint and soap???
I switched to mixing 70% water with 30% isopropyl alcohol. I mixed up a bottle of that and use it to thin my craft paint. Make sure you premix the water/alcohol before adding it to the paint.
50/50 seems a bit thin. I use about 2/3 paint, 1/3 thinner.(30-40 PSI) Using this method seems to give a much tougher finish than using washer fluid.
I usually try to shoot a thin coat of cheap spray primer first but it’s not necessary. letting your coats dry completely is a must!
Actually, DPM kits are thick styrene. I’ve never washed any of my DPM kits before painting. I even hand brush the walls with Pollyscale (acrylic) paint and have yet to have any problems with paint adhesion. It could possibly be the brand of craft paint.
I agree with Loathar and Tom. Use the 70/30 mix of water/alcohol and thin to whole milk consistency for airbrushing @ 20-30 psi using a medium or #3 tip in the airbrush.
DPM pruducts are in fact styrene not resin. I could be wrong, but I think one of the folks of Magnusen (resin kits) started up DPM, which would account for the simullarites, (thick walls, cast in windows and doors), but this could just be hobby rumor.
Acrylic paints, while quick to dry to the touch, can take as much as 2 to 3 weeks to fully cure hard. Once hardened, there as hard as anything else.
As Tom , I also have never washed a building model, I just gvie them a few puffs of air to blow any dust off and then paint them. Make sure you’re buying acrylic paint not Tempera. I have used many different brands of acrylic craft paints, Modelflex and Pollyscale, all with great results
OK…I’ll not argue that. In fact, I just read that they are styrene on their website. They just don’t look like injection molded styrene to me. Just looked more like a poured casting. Thanks for clearing that up.
I had a Rix Oil Tank that was washed with Dawn Dish Soap and warm water after assembly. The resulting surface was perfect and free of oils, fingerprints etc. It took the Waterbased paint correctly the first time without flaws.
Ive started to do the same to the walthers Modulars parts that recieve paint.
I know it’s not exactly the DPM stuff here but I bet the plastic needs washing (AND all dry) before paint.
I have both DPM building kits and the modular wall collections and the plastic used in each feels different from the other; they might be different formulations of styrene. That being said, I’ve not had any problems brush painting the kits with Modelflex, Accupaint, or other acrylic based model train paints. Have not tried artists acrylics, which at least in the Liquitex tubes is on the order of viscosity of toothpaste.
Something I have done to wash wall sections that give me trouble with paint adherence is to use a vinegar/water mix, along with the cheapest dishwash soap I can find. The acid in vinegar tends to cut grease I find. The thing with soap is to find one that doesn’t have anny additives that will soften skin - it leaves a scum on the wall sections.
The reason I wondered if the plastic is different is that the LHS guy told me that DPM uses a somewhat different plastic then the Walthers kits and that regular plastic cement may not work as well. I am not sure thats the case, I have a feeling its more related to the need to make sure your parts are sanded square for a good weld.
Anyway, this weekend I experimented a bit and came to the conclusion that I was mixing my paints to thin and using too low a pressure. I ended up using a pressure closer to 35-40 with my craft paints and closer to a 1/3 thin. Perhaps the air guage on my craftsman compressor is less accuarate then I had hoped. I plan to get a regulator/water trap at some point so I dont have to walk back to my compressor to modify pressure.
I still wasnt happy with how my model came out so after reading some more threads I decided to try cleaning the paint off and putting on some solvent-based primer I had. That was last night, I have not tried spraying since I primed.
To help me get a feel for what my paints should be mixing like as far as consistency I got a bottle of the black and white createx opaque airbrush paint at a craft store. It was thicker then I expected and required more pressure then I expected when painting clouds on my backdrop. I do hope to pick up some badger modelflex paint next time I see some to try out a pre-mix intended for modeling.
Air brushing seems to be one of those areas where 15 minutes with an experienced teacher would probably do tremendous good but such is not available to me. Much more practice is in order before I attempt the paper mill kit my wife got me for dad’s day!
I don’t know if the particular red you are using is already pretty thin. I’ve found that, even after shaking, Floquil or Pollyscale Oxide Red goes on somewhat thin right out of the bottle. If your oxide red is the same, that would collaborate your findings.
Yes, it does seem like the red oxide is a naturally thin (from a pigmentation view) paint… I used a createx “red oxide” and a liquitex “soft body red oxide”. The liquitex was much better then the createx but didnt have quite the right color I was looking for.
I am hoping using a primer will help the paint to shine out a bit better.
I will need to be a little careful if I spray other colors not to make assumptions based on my red oxide experience.