Since I get exactly zero e-mails asking for advice, I thought I'd preemptively deal with a tricky subject. The basic ideas were covered in the comments from the above article, but expansion is useful here.
Tanks - What Should Know
Painting tanks can be a pain in the dick. There are a lot of flat areas on a comparatively large model. This is especially shitty if you've decided to go with any kind of mechanized list. I'm looking at 7 tanks with my Space Marine list with another 4 on deck for later expansion. IG armies can be looking at even more. Maybe this is and the general cost of the kits are why people are reluctant to mechanize.
The base coat is the largest hurdle.
You have three basic choices for this:
Get an Airbrush: This is what I consider the best option as it gives you the most flexibility and the most control. Unfortunately, is is also the most expensive option by far. A decent double action airbrush and compressor is 200 bucks. There's also a bit of a learning curve.
But you get a tool capable of turning almost any paint into a spray, you get a ton of ability to do camo patterns and you get a lot more speed & control. I've talked about this in the past so I'll stop here.
Bottom Line: don't get the airbrush unless you really, really want it. It worked out for me, but everyone is different
Use a Regular Old Paint Brush: This is the worst option in my opinion. Its time consuming and its extremely tricky to get a smooth coat of paint on something with so many flat areas.
If you are crazy enough to go this route, get a larger flat-ish brush and be prepared to do mulitple coats to get a solid base. I would also advise that you be fairly ruthless when it comes to eliminating brsh strokes. Nothing fucks up a paint job quite like it.
You also have very limited ability to do camo patterns. Feathered edges are hard unless you have some kind of spary. You can use scrumbling and stippling, but they tend to leave artifacts on you paint. Hard line patterns are also do-able but will also take a ton of time to do right.
Bottom Line: DON"T DO THIS! You will drive yourself crazy and the finished product isn't worth the time.
Get Some Spray Paint: This is one I've been giving a lot of thought to. Probably the best comprise between the expense of the airbrush and the cheapness of the regular brush in terms of speed and control. You get most of the speed of the airbrush and a good chunk of the options for camo schemes and all you really have to do is buy paint. Upfront, I have to be honest in that I don't spend a lot of time with this method since I got the airbrush.
There are a ton of military color sprays out there and as general hobby shops are fairly easy to find, you shouldn't have too much trouble getting your hands on some Tamiya or Model Master sprays.
Words of caution: just because it's a spray paint doesn't mean that you get to ignore the golden rule - use multiple thin coats instead of one thick (and potentially runny) one.
Also, don't be shy about gloss paints. You're going to seal the miniatures anyway and that dullcaot will take the sheen off quite nicely.
The only real bummer here is that this option is great, so long as you aren't married to a particular color. For the most part, military model spray paints are based on actual real-life camo colors. Not so bad when you are also using some standard military color brush paints. Not so good when you're doing space marines and you want to find an exact spray match for your Ultramarines.
Bottom Line: the best option in terms of economy with solid speed and quality. Especially good for IG players whose tanks don't need to be the same color as their soldiers.
General Tank Painting Advice
No matter what you've decided on for base coat method, the following will be useful.
Tank Treads: These can be tricky to pant once they're on the tank. They can make it hard to get to visible surfaces and weathering them is often messy. I leave them off and paint them separately and attach them later. This leads nicely into...
General Assemble Advice: Depending on your preferences, it may be a good idea to leave detial blocking parts as separate components while painting. This can make it easier to get to otherwise hard to reach areas. Leaving the turrets as separate pieces altogether can ease storage concerns. Depending on the model, it might also be a good idea to pre-paint hard to get at areas DURING assembly.
Camo Patterns: Camouflage is the primary reason I advocate some kind of spray paint (can or airbrush). Once you mark out and mask off the pattern, its a simple matter of spraying a new color on the tank.
- A hard, jagged pattern can be achieved with simple masking tape.
- a softer, more curvy pattern can be achieved by marking of the boarders with strips of blue-tac and then filling in the rest with masking tape.
- an amazing feathered edge can be achieved by using tiny amounts of blue-tac to affix strips of paper on the tank leaving a slight gap between the surface of the tank and the paper.
- A nice mottled effect can be achieved by lightly spraying another color over the tank or on various patches.
- lastly, you can get a neat effect by using a round brush to stipple additional colors on the tank.
Panel Lines and Shading: You're tank model is large enough that you don't have to worry too much about shading it. Most of the shadows you need come free courtesy of the tanks size. What you will probably want to do, however, is shade the panel lines.
If you're rocking an airbrush, you can use a technique called pre-shading. Basically, you paint the panel lines black and then paint the base coat in such a way to preserve some of the pre-shading.
Otherwise, you're best bet is to use a lining technique. After you paint the base coat, you can flood the panal lines with thinned down paint. I've had the best luck with oil paints, but they take much longer to dry. Whatever type of paint you decide to use, the most commonly used colors are black and various shades of dark brown (equivalents to raw and burnt umber).
Highlighting: This is one of the few times where I tell people to drybrush their highlights on. Tanks have a lot of hard, straight lines and are very large. This makes dry-brushing quite easy and allows for a much nicer effect overall than drybrushing a regular miniature.
I do not recommend trying to do any kind of blended highlights as doing an entire tank by hand in this way is incredibly time consuming. Agian, no reason to drive yourself crazy over the course of 7 tanks. Line highlights can be useful if done the right way - by using the side of the brush against the edges of the tank
Weathering: Adding some wear and tear to your tank can really add to the model as a whole. The techniques for this are legion, often complicate and often require special materials.
Some basics, however:
- You can get a chipping effect by dipping the ubiquitous gray packing sponges in paint and the dabbing them along the edges of the tank and in places that would see a lot wear.
- Watering down some rust colored paint and applying it to rivets creates a neat effect. Bonus points for using a paint brush to streak it down.
- Tamiya Smoke can be a great way to add oil splotches to things
- Mud around the base of the hull can be applied with basic drybrushing and stipling techniques. Just make sure to use more than one color to keep it interesting.
I've got some more nuggets of wisdom scattered around this site. Other place to look would include military modeling forums and general military model sites. The Mig Productions forum is just one solid example.
How to books are also extremely valuable sources of information. Osprey has a pretty large series of books. Most of them focus on specific vehicles, but they all cover the same basic stuff.
If you're feeling saucy, GW just released a book on painting their tanks. I haven't looked at it, but it does have a number of step by step projects. They'll probably talk your ear off about the GW spray gun though.
[EDIT:] I totally forgot to add some more sagely advice.
Handling your tank: One of the other, more insidious, problems with painting your tanks is the tendency for them to require more handling during the painting process. If you're like me and you like to hold things and change angels a lot, you'll most likely be touching the tank a lot. This puts you at higher risk for damaging the work you've done so far as friction and your hand oils start undoing your progress.
My advice is to either learn how to paint without touching the tank too much - some form of small block or pedestal can be useful to raise the tank into better positions - or, leave part of the tank disassembled in such a way that you have some natural hand holds.