My name is Chris van der Linden. I have roughly 15 years experience with painting metal and plastic miniatures. I started the wooden modelship building hobby only recently, about 2 years ago and noticed a lot of people are struggling with how to paint their cast metal ornaments to a satisfying standard. I decided to write down my experience on this topic for everyone to enjoy.
Note: this tutorial focusses on metal colored finish right now. I will add an additional explanation on how to do different colors.
Easy for anyone
One thing I have learned is that painting is not as difficult as it seems. Sometimes people are amazed at the small details, believing they need a 1-haired brush and loupe to pull it off. This is NOT the case. Even with 2 simple steps you can have great looking (repeatable) results.
Disclaimer
Please use this guide and techniques to your own discretion. Always use a tester if you are unsure about the results. Each situation and personal preference is different. I can say however that I have used all of these techniques a lot without problems. I provide these tips for your satisfaction, this is by no means "they best way" to do it...
1. What paints to use?
Painting cast metal parts has its origins in "tin miniatures" painting, the toy soldiers we all remember. A common misconception is that painting on metal requires Humbrol or Oil paints. This is not true anymore.
Brands like Citadel and Vallejo have developed acrylic (water based) paints that have exceptionally good coverage even on un-treated metal parts. This is great because they are much easier to work with. Humbrol is tricky to thin down and mix with other colors, requires turpentine to wash and takes long to dry. Oil paint takes even longer to dry...
Long story short: I always work with water based acrylic paints from Citadel and Vallejo on metal cast parts.
It dries fast, is easy to thin down, mix and work with. Add your wife/girlfriend's blowdrier and you can work even faster
Citadel paints tend to have rather funny names because they are used for fantasy/sci-fi minatures. So a certain red might be "Blood Red" or "Merchrite Red". This is their alternative for having "paint numbers". Both these brands also offer specialist paints such as instant rust, metallic colors, texture paints and weathering powders.
2. Preparation
a. Removing Flash / Mold Lines
As a result of the casting process most models have Flash and Mold lines. These are unwanted and you get a nicer looking part if you take some time to remove these. Flash is a bit of excess material that has run in between mold parts, usually giving a thin sort of "outcropping". Remove with a sharp knife or file. Mold lines are thin lines where the two mold parts are joined. Most of the times these run along the "sides" of a miniature and can be easily filed down to a smooth surface.
b. Shape your part before you paint
Some cast metal parts (depending on their material) can be deformed easily. Sometimes they are already slightly out of shape, deformed coming out of the box. Before you start painting, make sure you shape your part so it fits on your ship. Take as much time as you need because after painting you can't do this anymore. Paint chips easily.
c. Wash/rinse your parts (optional)
During the casting process so called "release agents" are used to ensure the cast pieces come free from the mold easily. This is a greasy kind of substance sometimes left on the miniature part. It can cause trouble during painting. If you want you can wash your cast parts gently in warm water with a bit of dishwater soap. Then wash clean with water and let it dry on a cloth. Use a blow drier if you are as impatient as me...
3. Primer
While paints such as Citadel and Vallejo give pretty good coverage on metal parts straight away, it usually helps to primer your castings first. This not only helps prevent paint chipping, it gives a perfect 'undercoat' for your paint work.
I always use acrylic paint spray cans to prime my metal and plastic parts. Depending on the colors used lateron, I either prime with matte black, or gray. Black being ideal for darker colors such as green, brown, gold etc. Gray being a perfect base for colors such as Blue, Red, Yellow.
a. DIY sprayboot (for free)
An easy way to prime your metal castings is to place them on a cardboard box. You can use a piece of double sided tape to "lightly fix" them in place. The box will allow you to turn your models around, without needing to touch the parts with your hands. (see what I did there lol). If you cut the front pane of a box out and place the castings inside it, you have a cheap DIY spray "boot".
b. Correct way to spray
Go outside, then spray the parts from about 30cm distance. Don't keep the nozzle pressed continually. This will un-neededly flood your fine model. Try to do short "puffs" while turning the box around, covering all angles. This will give a thinner coverage, avoiding flooding your castings.
c. Avoid warm sun
One thing that can give bad coverage is spray painting in warm direct sunlight. Due to the heat, the gas with paint bubbles will partially dry in "mid air" while traveling towards your model. This will cause tiny droplets to form, giving a coarse finish.
4. Painting
Now that you have prepared and primed your castings, it is time to paint. Whoot!
a. Make it easy for yourself
Often the parts you need to paint are quite small, making them difficult to handle. Smudging your own work. An easy fix is to stick a piece of double sided tape or gummy on old paint bottle. Then stick your model/miniature/ornament on top of that. Now you can hold and maneuvre this thing, without having to hold the actual casting. This is also somewhat less strainful on the hands during long paint jobs.
b. Color block
Likely your model will now look black or gray. The first painting step is to apply what we call a "color block". This basically is a solid appliance of the "main" color of the object. When done you have a full opaque colored object, not looking very impressive... yet ....
In this picture above: top brown parts are primed, then painted brown base color. Bottom right is the original "bling" casting.
C. Wash / Ink
Now comes the million dollar trick that will take you 90% of the way. Most miniature painters use what they call a "wash" or ink. This is a water thin paint that flows onto the model easily, ending up darkening the recesses, while staying clear of the raised areas.
This gives two results: The model becomes darker overall. Plan ahead for this, use a ligther color block if needed to begin with. It also gives a lot of your detail without manually painting. So all the small details in your cast ornament suddenly "spring to life" without any talent needed. Citadel offers specialised washes in different colors which are absolutely amazing.
Use a larger brush and royally "flood" your model with the wash. It dries up subtler than it initially looks so don't be afraid to go bold with this. Washes and inks do take longer to dry. Set the painted part aside and give it a few hours to dry. You can speed this up using a blow dryer, but be gentle.
d. Add highlights
Once the wash has dried you can add highlights to your paint work. This is optional. You can go all out and add many levels of highlights, but usually one "step" is enough. You can simply use your main color block color, with 25% white or lighter shade color mixed in. Use a fine brush and paint some of the raised areas that you think should "catch light" in a natural situation.
e. Drybrush technique
Alternatively you can use what is called the "Dry brush" technique. For this take a larger brush, then load your brush with the highlight color paint. But instead of painting, first rub it allmost dry on a tissue so virtually no paint comes off the brush. Then "wipe" across the surface of your casting, the little paint that is still in the brush will "catch on" the raised areas of your model, not the lower deeper parts. This is an easy way to apply detailed highlights without having to manually paint them, which requires a more steady hand.
Drybrushing gives a more "chalky" grittier look. Painting highlights by hand, a more smooth silky look. Apply to your own taste or skill level.
Examples of finished results
< I am collecting photos right now - will be updated -
The model No. 2 is ready (a little simplified option of a gun
http://modelshipworld.com/index.php?/topic/454-24-pdr-bronze-gun-le-fleuron-1729-by-garward-m-124/