I just recently entered the world of lighted models. I have seen many builds that talk about adding light blocker to the inside surfaces of the pieces that house the lights. However, no one ever mentions what this magical light blocking material is. I assume these are paints of some kind applied by a airbrush or other airisol method. I am finishing up my first lighted model now. As long as the lights are not too dim you cannot see the light bleed. However, in the dark the light bleed is obvious.
Sometimes it can be paint, but to block brighter light sources, one may have to use something like metal foil. Just be careful not to short your wiring on it if you do use it.
Aluminum paint is best for blocking light. They use a coat of aluminum paint on fabric aircraft to keep the UV from getting through the color paint and damaging the fabric. The fabric is clear doped first, then the aluminum, then the color. Takes very little aluminum to completely stop light.
Are there any paints that would do the same job? I have some rather unusual pieces that have little to no tolerance for foreign objects when put together. I have some aluminum tape that I will most likely use for certain areas of the model but it won’t work for all areas.
I would agree with Don’s suggestion of an aluminum/silver color paint.
I would think that to keep costs down you could use a silver spray can from a big box store instead of using your more expensive model paint.
In the case of close tolerances to some component where paint/masking etc. is impractical, perhaps you could use a silver ink marker, usually available in sets (with other metallic color pens) in many stores- I got some at the 99store
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