I notice how lots of people mask off the cockpit area with masking tape before spray painting (well duh). The problem I have is making the masked area fit. If I just use masking tape then cut around the canopy area, the masked area will often lift.
I thought that a good method might be to mask the real canopy sections, then glue them on with PVA wood glue. I'll be able to remove the canopy with little effort, the masking line will be all but perfect, etc.
I always glue the canopy in place first - or at least the windscreen, if I plan to pose the canopy open. I use watch crystal cement to glue my clear parts with.
I use Scotch tape to mask the clear parts of the canopy, leaving the framing exposed. Scotch tape makes for a very hard, crisp edge. I start in the corners using very small triangular chunks of tape - getting the corners near to perfect makes for a really good looking final result. Using a chunk of tape cut to a point instead of square is the key, here. Then I fill in with tape from the edges to the middle and burnish the edges down with a toothpick, after which I mask any open areas of the cockpit.
Then I airbrush - since everything is sprayed in place the overall result is far more uniform in finish, and that's the key at this point. It's important to remove the Scotch tape as soon at the paint is nearly dry (I use enamels) because the tape is so tacky. Then I can also use a sharpened toothpick to chase away any under-creep from the spray job.
I tend to use a mixture of both. The tape is easy to use, but no fun when dealing with curved frames. The metal foil is absolutely brilliant for any kind of shape, but the cheap stuff I use tends to leave nasty, sticky residue after I remove the foil, and I spend close to forever cleaning the windows afterwards. Can't help but wonder, is this a common characteristic of all types of metal foil, or something I brought upon myself by being cheap, and trying to use metal butter and/or chocolate wrappings?
I've always been afraid to use anything more aggressive than water and soap for cleaning, but I suppose if I use naphta for frames painted with acrylics, and alcohol for those painted with enamels, I might have a chance of not wiping of the paint along with the fog.
I use wrappings from butter instead of chocolate myself. Mostly the same process, but far less tempting to eat the 'leftovers'....