Painting Scale Models - Masking
Painting of scale models will often involve the use of masks. These masks simply block paint from areas were it doesn't belong.
Models with military camouflage will often need masking. If the separation line between colors is fuzzy (depends on the real airplane), camouflage can sometimes be free-hand airbrushed with no masking. However, for sharp separation lines (e.g. Spitfire shown below), or for spray-can painting, masking will be necessary.
Using the right masking materials will help ensure success. The mask material needs to stick well to the surface, but must be removable without pulling up any of the underlying base paint. Masks can be made with tape, film, or liquid.
Not all tapes are created equal. Of all the brands we've tried (many!),Tamiya masking tape is the best. This is yellow tape, available at the hobby shop in various widths, see below. This might be a little more expensive than regular white masking tape, but it will go down and come off without damaging your paint job. You can burnish down the edges to prevent paint creeping under.
The extra expense is worth it. We've also had good luck with blue house-painter's masking tape. Frisket film is another great masking material (see photo below). It's generally available in art supply stores, sometimes in the local drug store. It's a low-tack, clear film with a backing. It can easily be cut with a hobby knife to the required shape.
Since it comes in a large sheet, you can cover larger areas faster than with a roll of masking tape. The only disadvantage is that it doesn't go around compound curves really well, so at those points you can supplement it with masking tape.Liquid masking films are very convenient. The bottle shown below is Micro Mask, available at your local hobby shop.
Simply paint the liquid onto the surface needing a mask. When dry it forms a thin rubbery coating. Use a sharp knife to cut along the pattern, and remove the excess. This is obviously great for compound curves and surface detail. We use it all the time for masking off canopies (to paint the canopy frame).
To make the masks, use a photo of the camouflage pattern of the real airplane as a guide. A full-size painting guide is included in the better kits.
In this case, a photocopy of the camouflage pattern that came with the kit was secured to the top of the Frisket film, which was then cut with an X-acto knife. Another option is to get a sheet of glass (e.g. cheap picture frame glass), and cover it with overlapping strips of wide masking tape.
Lay the pattern on top and cut out the masks as before. If the color separation lines are fuzzy, and airbrushing these free-hand is not an option (lack of skill or equipment), you can adapt the masks to achieve the same effect. Use flattened loops of tape, or "Blu-tack" to attach paper masks to the model.
The slight distance offset from mask to model creates the softer color separation lines. The Spitfire below has been masked mostly with transparent Frisket. You can see it easily on the wing (the darker gray areas).
Yellow Tamiya masking tape has been used in some of the more curvy spots, or where there is raised surface detail. There is also an area masked with Micro Mask (blue area on top of fuselage, just in back of the cockpit).
There is also masking tape applied to the edges of the wing, and the underside of tail and fuselage; this prevents top-side over spray from reaching the bottom.
Next step will be to spray the second camouflage color.