Saturday, October 23, 2021

Gunpla Painting with Bosny

 This is another article converted from a Facebook Note post.

You’re getting tired of simple snap builds and fussing over those nasty stickers, and you want to try your hands in painting kits so you can show off your kits in a better, ugh, light. You can always try hand brushing, which is simpler, but, not really a simple skill to learn because it will test your patience, dexterity and ability to focus. Handbrushing is very much a specialized skill that you will have to learn eventually especially when detailing kits.

Though there are people who could jump right into airbrushing, it’s a bit tedious a process involving mixing and cleaning and a whole lot of maintenance (but, eventually, if you’re really up to it, you’ll get there).

So, the alternative is using spray cans. Though there are hobby grade paint in cans, like Tamiya, Mr Color and recently, Vallejo, they are a bit on the expensive side.

What is a
poor guy on a limited budget to do?

The answer is of course, Bosny Spray cans. There are other industrial type cans available but, let’s concentrate on Bosny since it’s mostly-widely-more available and thus easier to access, especially in Asia. (As an aside, check your local hardware for equivalent brands). The main difference between hobby-grade cans and industrial cans might not just be the formulation, but also that the hobby-grade has a finer nozzle.

Now, the stuff here can and might also be applicable to airbrush painting, as they are of course using similar concepts, using pressurized air to atomize paint, to put paint on your kits.

In a previous article, I wrote about Hobby Paint and Solvent types. Bosny is not a hobby paint. It’s an industrial paint that’s designed mainly for retouching paint on vehicles. In some cases, it’s used to paint decal-like designs. It’s also used by graffiti artists. What’s more, Bosny is listed as Acrylic-Lacquer-Epoxy, which is something that confounded a few people since they didn’t think lacquer and acrylic on the same phrase, let alone, in the same can, was possible (but that’s a different story).

Update: Bosny has reformulated its paints, dropping the epoxy component altogether. Bosny paints are now 100% acrylic with lacquer component.

Being an industrial paint and also being cans, a lot of people get the misconception that it cannot be used on Gunpla. “Bosny Paint is too thick” is the most common sentiment. Well, to be honest, any paint, whether it’s hobby grade or industrial grade can be used on Gunpla, it’s just that people expect to have the same, exact results when using one or the other. There were people who joked (and some who seriously asked) about using Boysen paints on Gunpla. Seriously, if it was properly thinned, and depending on the paint type, you probably could. All types of paint, after all, are made with the same chemicals, but of different proportions and additives. Maybe I’ll try and , and depending on the paint type, you probably could. All types of paint, after all, are made with the same chemicals, but of different proportions and additives. Maybe I’ll try and experiment with Boysen paints* one of these days.

Now, quite recently, since there will always be new people getting into the hobby (their means of getting into the hobby notwithstanding), we’ll normally see people asking the same questions asked and airing the same sentiments aired before. Let’s tackle them all (this will be updated as needed).

  • Bosny paints are too thick. Well duh! It’s an industrial type of paint. It tends to really be thick because it’s designed to cover large-area objects, like cars and car parts. But, is the paint really that thick?
       Yes, and no. There are certain Bosny variants, like the designated Metallics (metallic Red, metallic Black), that are really thick no matter what you do. I steered clear of those variants after using them once. But, from primer to candy tone, you can control how thick the paint is by fighting your instinct to spray wildly and impatiently, which leads us to,
  • Bosny has no spray control. Again, yes and no. Bosny only has one setting when it’s new: male adolescent in puberty. Depressing the nozzle will tend to spray out everything it can because of its initial pressure. But that’s where you, the intrepid modeler cum painter cum in (puns intended).
       With Bosny cans, you become the spray control by learning how to control your finger as you depress the nozzle. You have to practice a very fine motor control of applying enough pressure on the nozzle at a relatively very short amount of time, like, less than a second. Instead of spraying continually like you could with an AB, you have to spray in short, quick bursts, and oftentimes adding a slight movement while rotating the part to cover larger areas or parts evenly.
       As it expels air, it loses pressure. Halfway through, you’ll find that there isn’t enough spray pressure anymore, the paint starts to spurt, and you have to adjust how you spray as well. Recently, I discovered that I have to get a fresh can when it feels half as heavy, because the pressure would probably also be just half as strong, as the amount of paint in the can is more or less directly proportional to the air pressure left. I can still use the can after its halfway point, but it’s touch and go the rest of the way. The paint is still viable, but, without enough pressure, it won’t give consistent and favorable results, so the only option at this point is to decant, thin, and apply it with an airbrush.
  • The spray coat is uneven. It’s because you don’t know how to use it. It’s either you’ve depressed the nozzle too long, or, you didn’t rotate the part, or you didn’t move the can during the short spray burst. To add, some practices, like painting on runners and painting assembled kits can also contribute to the issue, especially when you’re just starting to paint with cans.
  • There is paint clumping in some areas. Ah, yes. The dreaded overspray and pooling. The bane of all modelers and humankind in general. This happens when you spray too close and too long, and when you paint an assembled kit, instead of doing it properly, painting parts and/or sections individually.
       This also happens with an AB that’s improperly set up, or paint that is improperly thinned. Whereas previously, the spray distance is about 6 inches (15cm), I found out that 12 inches (30cm) or more is ideal. This allows the paint particles to partially dry midway, level quickly as it lands, and become fully dry a few seconds after.
  • The surface is curly. Some people call this the orange peel, which is actually incorrect, since it should be orange skin, describing the texture of an orange’s skin (orange peels however is an actual thing used as an ingredient in cooking and baking), but for the sake of convention, let’s stick to the term. This also happens with ABs and results from several factors:
    1. the underlying paint coat is still moist when you laid down the successive coat, and the upper coat dries/cures faster that the previous one/s. Solution: Wait for the previous coat to fully dry, or better yet, fully cure, before laying down the next coat. Ideally, the time between coats should be at least an hour or so, longer during cold weather. I can work quickly with 30 minutes between coats, but that’s stretching it.
    2. the surface is not sanded and primed. A lot of lazy people skip sanding and priming because they simply do not have the time, opting for uneven painted surfaces and expecting everyone would be okay with it (Gunpla is freedom). Well, I guess that’s okay, for some, but, if if you post it, don’t expect everyone would be okay, let alone impressed with it, especially seasoned modelers and painters who don’t do things half-assed and half-baked.
    3. you painted during a storm, or during fluctuating humidity. Although this is a very tricky proposition, I’ve painted kits during bad weather and got good results because I know when to lay down paint. It’s a bit hard to explain, but I noticed that I kinda sense when the weather changes. The air becomes humid and heavy and it’s extreme cold and hot in front of and away from a fan respectively. Bad weather is not an ideal time to paint, but, if you must, the best time to paint is when it actually starts to cool, an hour or so after it has started raining. It won’t be a good time to do candy tones or top coat, but priming and base coats should be fine.
    4. the previous coat is uneven, or you tried to do a full coverage in one go. Though it is possible to accomplish that, conditions must be ideal (humidity, temperature). You must mist in thin coats, and let the coat cure for an hour or so before the next coat.
  • Bosny is just a bad paint medium. Okay. Okay! I’m kind of an unofficial Bosny ambassador ever since I started painting Gunpla, or anything for that matter, and quite recently kind of become a semi-official one after Bosny Philippines gave me a whole bunch of cans and stuff after they’ve seen my blog and FB page. Bosny is only a bad medium if you’re bad at it. I repeat, gave me a whole bunch of cans and stuff after they’ve seen my blog and FB page. Bosny is only a bad medium if you’re bad at it. I repeat, Bosny is only a bad medium if you are bad at it. When I started using Bosny, I’ve committed all the errors you can think of, from overspray, to uneven paint and even orange peels, because I didn’t know what I was doing. But, after a while, I got to understand how the medium works and how to make it work on any Gunpla scale.
  • Airbrush is better. Well, duh! But, apropos (my favorite uncommon word), it’s more like an airbrush is a better tool. I’ve written about this before because there are hardcore AB modelers that seem to interpret my use of Bosny as something being better when I said “I can achieve close to AB results with Bosny.” Context notwithstanding, there is nothing in what I said that even comes close to saying Bosny is better.
       The thing is, an AB, like Bosny, is a tool. If you don’t know how to use a tool, it won’t give good results. So ultimately, it’s still on you. I’ve seen a few projects done with Bosny that are comparable to those done with AB. And seriously, there are those done with AB that do not look that they were done with AB.
       Also, if you are going to use an AB and your color scheme is rather common and mediocre that it looks like someone else’s work, you can’t really diss someone else’s work that looks way better than your mediocre AB-painted kit. In fact, it’s really harder to achieve good results with Bosny because of all the factors I mentioned, and it takes a lot more skill and patience to get good results. If you’re using an AB, and your results are mediocre at best, what’s your excuse?

Thin as sleeves, thick as thieves.

Now, to summarize these are the factors that affect how Bosny paints (and hobby paints in general) behave:

Spray pressure. Bosny only has one setting. Fresh, new cans have very strong pressure and this goes down quite significantly as the air gets expended over time. With AB, consistent pressure can be set on the compressor, and spray strength/volume can be adjusted on the airbrush. Mini compressors mostly have a single setting, around 17 to 20 psi, but there are mini compressors with pressure knobs. With Bosny, the only way to get actual spray pressure control is to shorten the spray burst.

Humidity. Contrary to popular belief, it’s not heat or the temperature alone that can affect paint during spraying, but rather, the overall relative humidity. Humidity is the amount of moisture in the air. High or fluctuating humidity can cause havoc on paint as it lands on the part you are painting since moist air can get caught with your spray bursts. Do you know why cold glasses sweat? That’s moisture condensing on the surface of the glass. Now, during a thunderstorm, everything solid gets cooler, but, the air can remain warm. When moisture gets caught on your spray burst and lands on the part, well, you get the idea. This, along with a cold part, causes topcoats to frost.
   This also happens during a cool sunny day with relatively high humidity. With AB, this is minimized by the use of moisture traps. Since AB spray mists have smaller particles, and the pressure burst can be controlled, you can spray the part as close as you can without over-spraying.
    Warming the Can may seem to help at times, but it really doesn't. As humidity fluctuates, it would have already fluctuated after you've warmed the can.

Curing times. Let’s face it. No paint or paint tool can ever get a complete layer coverage in one go. That’s why we paint in successive coats. Bosny has a quick-dry formulation, but, it still has a relatively long curing time just like most paints. When you do successive coats, with the previous coat still curing, the overlaying coat can dry and cure quicker when the humidity changes. So, it’s best to allow all a safe curing time between coats. For Bosny, an hour or so, or longer is ideal.

Spray distance. During the course of using Bosny, a distance of 12 inches is about right to properly mist the paint. Too close, and the paint will be too moist that it will cause over spray. Too far, and the paint would end up like small particles of dust over your part.

Sanding and Priming. Two important steps you should never skip. When you decide to paint your kits, don’t do it half-assed. You need to commit to the endeavor. The primary purpose of sanding is to level and smooth the surface of the parts you are going to paint. While de-nubbing parts, you introduce micro scratches and cracks on the plastic, without realizing it. Though most parts do have a little flexibility, applying pressure on certain parts leave very minute cracks on the surface that are not visible until you apply primer and paint. What’s more, nubs will always have an uneven surface, no matter what tool you use. Not even god hand can cut that clean. You’ll still have to sand that nub mark away because it will show under the paint. Sanding also removes that built-in shiny surface coating that exacerbates the plastic texture underneath. So, if you see swirls and curls after you paint, well...
   Priming, on the other hand gives a smooth surface for your paint to latch on. Primers are formulated differently, as such, they will latch on to most plastics. Certain paints don’t latch properly on plastic, even sanded ones, hence, priming.

Addendum: Using hair dryers to dry paint on plastic is a bad idea.

Check these links for more information:

*I made that statement as a half-serious joke, which is something I would probably test one of these days, but apparently, based on feedback (or rumors) from certain modelers, there is a brand of local hobby paint that is actually just thinned house paint (hence the inconsistent results).

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