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Duplicolor Paint problems


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As Dave stated, lacquer almost always requires a clearcoat. If you are getting a milky haze in it, that may be a condition known as "blushing", caused by humidity. Back in the old days when dinosaurs roamed the earth and I worked in autobody, we would wait for the paint to dry, than buff out the haze. If not successful, a repaint was in order. But the clearcoat part... buy a compatible clear.

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More than likely you aren't doing anything wrong . It's the moisture in the air . High humidity is a problem because a lot of paints absorb moisture . This causes them to get a cloudy or milky appearance . Primers and lacquers are the worst .

If you give it a day or more to dry or gas out completely , sometimes it will disappear and you will avoid having to strip the paint and start over .

Good Luck .

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Like others have mentioned, laquers and humidity do NOT mix well together. It's just the nature of the beast. I have used duplicolor on numerous projects and have only had a few that didn't require a clearcoat to shine them up. I was going to clear them anyway so it wasn't an issue... I've noticed that Duplicolor Truck and Van paint is acyrlic laquer. Their regular automotive paint is acyrlic enamel. Duplicolor may be the only supplier out ther that offers a Laquer paint in rattlecan... Anyone know for sure?

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Older DupliColor comes in two varieties- lacquer that doesn't require a clear coat, and base coat lacquer that does (usually denoted by a "CC" on the can). With care and effort, these paints can polish out beautifully- both can exhibit surface texture and blush if spraying conditions aren't ideal. I have primarily used the ones not requiring clear coat and will polish the texture and any blush or milkiness out of the paint as soon as it has cured enough to do so.

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^^ This is DupliColor Nissan Cherry Red Pearl over DupliColor red primer.

This paint job had a little bit of blush/haze from humidity as well as a fair bit of orange peel texture that was knocked down with 1000 grit sandpaper. The paint was re-coated in thin spots and then polished with Bare Metal plastic polish on a flannel rag- no clear coat- it is all in all a beautiful product to work with and is pretty forgiving. I have been meaning to try the newer DupliColor lines to see if they are as nice a paint as the older auto touch-up aerosols this paint is from.

IMG_3894.jpg

Edited by gman
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More than likely you aren't doing anything wrong . It's the moisture in the air . High humidity is a problem because a lot of paints absorb moisture . This causes them to get a cloudy or milky appearance . Primers and lacquers are the worst .

If you give it a day or more to dry or gas out completely , sometimes it will disappear and you will avoid having to strip the paint and start over .

Good Luck .

The "milky" appearance is caused by humidity, which causes the surface of lacquer to solidify before the liquid underneath has a chance to evaporate. It's called "blushing". To avoid blushing with true lacquers, pay attention to the weather: If it's high humidity outside, and you are outdoors, blushing will happen to some degree. However, it's a known fact in say, the furniture industry (which uses a lot of acrylic lacquer, particularly in restoration and refinishing) that spraying lacquer indoors during a heavy thunderstorm actually does not result in blushing--a heavy rainstorm outside is actually sweeping the humidity out of surrounding but sheltered air (learned this from my brother and his son, both of whom are museum accredited antique furniture restorers and professional cabinet makers--they use clear acrylic lacquers almost exclusively) "Blush" can be eliminated by simply polishing out the lacquer, or of course, applying clear lacquer over it after the extra humid conditions have gone away. Of course, painting indoors in winter in most of the country, certainly in warm weather with air conditioning, will eliminate almost all of the problem..

Of course, in the real world, painters spraying lacquers use retarders to slow the drying time of lacquer in humid conditions, but that's not really an option for us plastic model builders--retarding the drying time of lacquer on plastic just gives more time for the solvents to penetrate the plastic surface, and that causes crazing. But, we can, as modelers, reduce, in fact, virtually eliminate crazing and even blushing, by using an airbrush.

OK, so now I've used the often-dreaded "A" word here. But, an airbrush can be used to lay on lacquers in almost micro-thin coats, which dry quickly on their own, minimizing (even eliminating) both crazing and blushing. For more than 40 years, I used acrylic lacquers almost exclusively, save for the existence of AMT lacquers in the years 1962-their demise about 1973, and the advent of Tamiya lacquers in the early 2000's, followed by Testors Modelmaster lacquers a few years after. I can say, that with the exception of a couple of Gunze kits, and a few original AMT 1958-1959 3in1 kits, I've never experienced any crazing and almost NEVER any blushing using automotive acrylic lacquers, even using model airplane dope on a few Indy car models I built. I still have a pretty good stash of leftover nitrocellulose lacquers from the late 1940's/early 1950's that I cabbaged from an old body shop that closed in 1973 and have used those on model cars more than once (acrylic lacquer was first developed by DuPont for General Motors and introduced on GM cars in 1958--their "Magic Mirror" finishes that were highly advertised that year.

My trick? Not rocket science at all, frankly! I use the appropriate primer, almost always red oxide, as that is the color of primer for which almost all finish colors were developed to cover well into the 1970's, but very well thinned, and airbrushed on lightly. I can see, on most modern-made model car kits, a very light "frosting" of the plastic surface, which is actually a slight crazing of the surface, but by being patient, and spraying on more primer (I tend to do my painting each coat in one sitting, but making pass after pass with the airbrush until I get the desired result) until there is some material buildup, the crazing goes away. I tend to see that as having "shock-proofed" the plastic surface, which in my observing the many projects I have painted over time, has been proven out (often when polishing out the primer, I have "burned through" the primer in spots, exposing bare plastic, and when either applying more primer, or going directly to color coats, no crazing happened in those spots of bare plastic. OK, so that's un-scientific, but I've won a few awards over time doing paintwork thusly.

Another advantage of using an airbrush is, as I mention above, the ability to get micro-thin coats of paint, which won't bury the surface details of the model (chrome trim, scripts , that sort of thing). Rattle cans, by comparison, squirt, even glop paint on so thickly that those details are softened, even lost, so some thought here makes sense. Why destroy expensive surface details if you don't have to? But this makes for some work prior to color coats: Why lay on a lot of color over rough, grainy primer? That just does not make sense to me! If you think about it, on real, 1:1 cars, painters don't do that! Nope, they will wet sand the primer to smooth, THEN do the color coats. I do this, by using Micromesh polishing cloths (actually cloth backed sanding cloths, with abrasives, for those not familiar with them). These were developed for the aircraft industry, and the US military (USAF and US Navy) in order to polish aircraft canopies for clarity and nearly perfect vision for the pilot looking through them--very important for a combat pilot in a dogfight with an enemy!.

So, my thing is to polish out the primer when I use it (I never use primer if I'm gonna paint with say, Tamiya or Modelmaster lacquers, UNLESS I've done some serious bodywork, and then only spot-priming where I've done any filling with putty!), as micro-thin coats of lacquer will reveal any imperfections in the surface. It's not necessary to make the primer a mirror shine, "satin" finish works just fine. But, that's far better than just shooting paint over the ordinarily grainy (think rough here!) surface of raw primers.

Yeah, so you say why spend the $$ on an airbrush and compressor? Well, for starters, this can be very much a "one time" purchase. A good quality hobby compressor should last for several decades (my first compressor, a Binks Diaphragm unit, lasted me from late December 1962 until it finally broke its connecting rod in 1987 after making a lot of clanking noise for about 5 years--my replacement, a Badger 180-1 is now 10 years old, shows no sign of failing anytime soon. Couple that with a Paasche H-series airbrush that is now more than 20yrs old, the cost of both isn't really that great. And, in the bargain, an airbrush used for painting model cars is very much like having a miniature spray gun, which will give nearly scale finishes (not to mention the virtually unlimited color choices!).

In the end, it's the use of proper equipment, and an understanding of how to best use lacquers that does result in nice paint jobs, not so much the choice of paints themselves.

Art

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...(my first compressor, a Binks Diaphragm unit, lasted me from late December 1962 until it finally broke its connecting rod in 1987 ...my replacement, a Badger 180-1 is now 10 years old...

So did you take a 15 year break from airbrushing?

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Patrick, you live in Meadville. High Humidity is the NORM here- Go to Home Depot and buy one of those temperature/ humidity gages (about 12 bucks)....Learn to check it all the time, until its a habit. It's currently 78 degrees with a 38% humidity factor right now, on my back deck just a half mile north of you....You can shoot duplicolor anywhere up to about 60% humidity....'Z'

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So did you take a 15 year break from airbrushing?

Nope, I pulled a Paasche diaphragm compressor (similar to the old Binks, and my current Badger 180-1) out of inventory in my hobby shop--but it failed pretty quickly. During my time in resin-casting, I had a Craftsman 3hp compressor in the shop--to pressurize the tanks for casting--just ran a line off of that. But when I went to apartment living, that noisy thing had to stay behind, so the Badger 180-1.

I did, however, go through a 7 year layoff from painting anything, as after I moved back here to Lafayette when Playing Mantis got sold off to RC2, I just didn't have room for a spray booth. That got corrected a year and a half ago, so now, I can paint again!

Does that all make sense? ;)

Art

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Hey gang,

I just painted a 1/12th Mustang. Its gloss black w/ flat black stripes. I used the Dupli-color Acrylic enamel spray paint in the rattle can. I did notice that it has a slight dull look to it. What should I use as a clear coat & how long should I wait before clearing it? This model was painted this past Sunday & yesturday. Unfortunately I have to paint in the basement with very little ventilation. Its all I have as far as where to paint. Also would I need to polish this or can I get away with just the clear coat? I can also feel the difference with the flat black stripes & the gloss black. I know I have to bring the stripes up level to the gloss black. Any info will be helpful. Thanks.

Kirt

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