Even after all these years, masking canopies is still my greatest obstacle in aircraft modeling.
I've used many different things, liquid masks, Parafilm, regular 'ole masking tape, Scotch tape, surgical tape, Bare-Metal foil... the list goes on.
Nowadays I try to see if there's an EZ mask available for what I'm building. There are several companies making EZ masks, Eduard and Cutting Edge (Black Magic Masks) being the two most prominent. I've had some good luck with them, but I admit that I haven't used them enough times to give a final verdict.
Basically, EZ Masks are made of a masking material cut to shape(s) in order to fit a specific kit. They're used for canopies, wheels and other complex or tedious masking jobs.
Cutting Edge offers several Black Magic camouflage masks, and many of the Eduard kits contain EZ Masks for some of the more complicated paint schemes.
There's also FastFrames, which are just the opposite of EZ Masks. Made of the same basic material, these are intended to be painted and applied to the model to give a nice clean line as well as a bit of realistic physical relief.
I used three of the FastFrames sets from a few years back and had mixed results. One was GREAT. One was okay, a few small problems and one was worthless.
I'm sure that not all of the EZ Masks will be perfect either. The last set I used was for an A-4 Skyhawk. Had a few small problems with it. Nothing major.
Another technique that I've used in the past is to mask all the vertical lines, then all the horizontal with plain 'ole masking tape, or whatever happened to be on the bench at the time. Then for curved or more complex areas I'd mask with a bit of liquid stuff. I've managed to elevate masking in general to an art, and whenever I mask sumthin' it becomes a minor project in and of itself!
This last technique I've described can be tedious and time consuming, but it works for me, especially if there aren't any EZ Masks around!!
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