Brushin' Up On Paint

By Ron Bell, #12907

You need to make sure whatever you're painting is clean and is free of grease/oil.  If it isn't, the paint won't stick to the surface or will puddle up and it will show up every bit of dust and/or cat hair left on the surface.  Just before you're ready to start painting, do two things.  One, wash whatever you're going to be painting.  I know you're told to wash the parts while they're on the sprue, but do it now, too.  As you work, your hands transfer oils and grease to the surface or just "stuff" in the air can get on there.  Take a few minutes and wash the thing in warm water with some mild dish detergent.  Use a soft paintbrush as a scrub brush.  Two, when you're done, let it air dry.  Don't rub it with a towel or anything else.  Remember 6th grade science when the teacher rubbed the comb on a towel and then made your hair stand on end?  Well, that's what will happen here.  Static electricity will develop and it will attract every dust particle in the room to the surface you want to paint.  Another point to remember on drying is to give it the appropriate amount of time.  That means for a simple flat piece, wait until it's not wet anymore.  However, if it's a whole wing, or fuselage or hull, let it dry over night or even for a few days.  Why?  ‘Cause water probably got inside the thing and it will take that water a lot longer to dry.  If you don't do this, as you turn the part to get the paint on, you'll feel a cool sensation as that water drips down your arm after marring that nice paint job you just did.  Some of you may have paint dryers.  You can use these also to dry a model before painting.  Whatever system you use, let it dry thoroughly.  Now let's get out the paint.

There’s another article in this section on the selection and care of paintbrushes.  Read it.  You'll need it here.  Putting paint on with brushes is at the same time the easiest and most difficult way to do it.  On smaller parts, paint goes on easily.  But on larger pieces, you need to be careful.

First, match your brush to your job.  Small job, small brush.  Large job, large brush.  Don't try to brush paint a 1/48 scale aircraft wing with a 1/4" round brush.  You'll get the paint on it, ok, but by the time your done, which will be a while, it will be streaky, full of brush marks and your brush will be caked with dried paint.  Use a wider, flat brush for large surfaces.  I know the ads say use nylon brushes with acrylics and if you're painting walls or landscapes, that's correct, but if you're painting a hard smooth surface like plastic, you'll have streaks galore.  The nylon is far too stiff.  It will scrape the paint off the surface, leaving streaks.  Use only soft bristled brushes like sable or camel's hair.

You now need to select your paint.  Oils?  Acrylics?   Lacquer? Finger?  (Just kidding on that last one.)  Your choice, but here are few words of advice.  Don't try to brush paint lacquers.  The solvents are too potent and you run the risk of literally melting your model.  Also, if you chance this anyway, never put a lacquer over anything other than another lacquer.  If you do, it will dissolve and lift the undercoat and you will have a big mess.  Another brush paint no-no is metalizers.  Universally they are made to be sprayed.  The main reason for this is that the solvent needs to evaporate almost as it hits the surface, leaving behind the metal flakes to be polished.  If you brush it on, you will be putting on too much solvent and the pigment will not spread evenly and you won't be able to polish it out properly.

Now mix the paint; don't just shake the bottle.  Get whatever you use for a stirrer and dig down to the bottom of the bottle and make sure all that "goop" is thoroughly mixed.  That "goop" is the pigment, and if it's not mixed, your paint will be more solvent than pigment, will not go on well and will not cover.  In addition, flat paints will not be flat unless you mix them thoroughly.  Some modelers use paint mixers.  These come in two varieties I know of, the one you attach to the end of a drill and the kind like a paint store mini-shaker.  If this is your thing, fine, but a simple piece of sprue or old screwdriver can do that job.

After it's mixed, get the paint to the correct consistency.  This will vary from paint to paint, oils to acrylics, color to color, brand to brand.  You'll need to experiment here.  As a rule of thumb, the paint should be about the consistency of creamy milk.  Not skimmed (watery), but creamy.  It should hold on the brush, drip freely but not be runny.  Again, experiment here.  I mentioned that some colors are different.  Reds, yellows and white do not cover well.  Gloss colors generally do not cover as well as flats.  These colors/types of paint may need special attention.  For example, if your surface needs to be, say, a gloss yellow, first paint a coat of flat white then flat yellow.  The yellow doesn't have to match the final color exactly, it only needs to be pretty close.  Then put on one or two coats of the final gloss paint.  The flat white lets the flat yellow cover and the flat yellow lets the gloss yellow look more yellow and finally, the gloss color gives the correct final hue and the gloss finish.

OK, your part is clean, you've got the right size brush and the paint is stirred with the right consistency.  You’re ready to begin.  Purists will say that you should dispense an amount of paint into a separate container and paint from there, not the bottle.  They have their reasons, but for our purposes, they are pretty esoteric.  We'll just stick to the bottle, unless your brush is too wide to fit in it.  If that's the case, put some of the paint in a jar lid (Not the paint jar lid.  That's a sure-fire way to seal up your paint bottle when you close it back up.), or some such shallow container.  Either way, dip your brush in and load it with paint.  Avoid dipping it in so deep that the shank gets in the paint.  It's almost impossible to clean if you do and eventually the brush will stiffen up like a board.  Draw the brush across the lip of the container to get the excess paint off.  (Word of caution here, be careful you don't tip over whatever your paint is in.  Put your paint jar in a blob of modeling clay or some such rig to keep it from spilling.)  You don't want it dripping on the way to the surface and you don't want to have to be spreading around a flood.  Then paint the object.  On small parts, that's pretty straightforward.  On larger ones, there are ways to avoid problems.

Let's say you're painting that aforesaid 1/48 scale aircraft wing.  Start at one end and draw the brush all the way across the surface diagonally in a straight line.  Do this over and over until you've covered the entire surface.  Try NOT to go back over an area, as this is when you get brush marks.  If you've got the right brush and the right consistency, you shouldn't need to.  The paint should flow evenly and create a smooth surface.  Paint from one end to the other.  Don't try to 'cut in'.  That's where painters go around obstacles like doorways or ceilings.  (Or in our instance, engine nacelles, fenders, turrets, etc.)  That works for them but in this instance will leave a definite line where the "old" paint dries slightly before you apply the  "new" and you get a line.  Keep a 'wet edge'.  That means keep painting in one direction and keep the edge of the paint wet.  That way when you reload your brush and start again, the paint flows together and you don't get a line.  On a big job, you may find that your brush starts to dry out and/or the paint gets thicker.  If it does, stop.  Clean the brush and/or re-thin the paint.  Don't just press on till the end.  You'll end up with a streaky, glommy mess of a job if you do.

Now, don't fool yourself that it's going to look great after one coat cause it won't.  Let the paint set up.  Not dry, but thoroughly set.  That means it doesn't smell like paint anymore.  For flats, that's a day or two.  For gloss, it can be several days to a week or more.  (I'm not kidding.  Gloss oil based enamels can take 7-10 days to properly set.)  The reason you need to let it set up is if you give it a second coat before it's set, the second coat will lift the first and you won't gain any additional coverage.  It could look even worse.  Patience here is your ally.  After the paint has set, give it a second coat, except this time, draw the brush on a ninety-degree angle from how you did it before.  This will help coverage and reduce brush lines.  If you want to be a fanatic, before you put on the second coat, very lightly sand the surface with 400 or 600 grit sandpaper.  Just enough to reduce any brush strokes and give the surface some tooth for the next coat to adhere to.  Of course, clean the surface thoroughly before you apply the second coat.

Once you've got the finish you want, you can apply dull or gloss coat the same way as you painted it.  It's usually best if you try to use an overcoat that is a different base than your paint.  For example, if you use oil-based colors, use an acrylic gloss or flat.  That way you know that the two will not interact and the overcoat will not pull up the color.  One note of caution here.  Before you overcoat your paint job, make sure the color coats are completely set.  If not, you could get some nasty interactions between the top and undercoats resulting in lifted paint or a cracked surface.

Whatever paint you use, one of the keys to good brush paint jobs is a clean, soft brush.  After you're done with a color, make sure you thoroughly clean the brush.  Remove all excess paint and clean it in brush cleaner/thinner and then wash it in soapy water and rinse it clean.

There are legions of modelers out there that don't even own an airbrush.  Brush painting is all they know.  If nothing else, its a good thing to teach younger modelers before they graduate to spray cans or airbrushes as it teaches good lessons about parts prep, mixing, paint consistency and keeping your tools clean.

That's brush painting.  Spray cans are another matter.  Stay tuned.

© IPMS Eddie Rickenbacker Columbus 2002

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