I have to agree with
Joel about all he wrote regarding the surface preparation and the main steps on achieving a "perfect" gloss.
The risk on one's health and the damage can cause on the airbrush have also to be taken into consideration when choosing the clear coat. But once the acrylic coats dismissed (too soft to get a good finish), all you have left is pretty nasty: lacquers, polyurethanes or 2K. I have used lacquers with good results but I had bad events too. On my
Ducatti Panigale I had to redo one side cowling four times: three times because of runs, one time for a shot decal - I assume the fault for all instances. I switched to solvent based polyurethanes because they have less tendency to run and they are milder on the decals. But, again, they are not trouble free. They're very sensitive to timing between coats: if you're too early - they run; if you're too late, they jelly up and bead up. Besides, they have a tendency to yellow if applied too thick. Now, 2K seems to have solved at list partially some issues of the former two and is hardest of all - hence shiniest of all. On the negatives, the prices are not friendly, the mixing procedures complicated and it can ruin your beloved A/B (I not dare think what drama will be to ruin my H&S Infinity for a bloody clear coat!) Tough choices.
Michael and
Luciano: you are mostly welcome guys! I'm glad to share my experiences with you! I
needed to try it for myself nonetheless! Yes,
Luciano I follow Paul from ISM as well and I knew his technique. Coincidentally, moments after I have read your post, he uploaded a new video dedicated to a 2K brand.
I have performed one last test today: I wanted to know how well 2K stands the rotary tool. I bought my
Proxxon a while ago but we didn't make best friends at first: the acrylic coats are too soft for it and peel off. I had big hopes with the polyurethane but the experience shown that actually I can get better finish by hand - the one achieved with the help of the machine was very smooth but somewhat hazy - it was lacking sharpness. Well, 2K is a different story:
Left: Alclad Aqua Gloss
Center: 2K, unpolished
Right: 2K, machine polished with Novus 2 Fine Scratch Remover.
I consider the performance quite good because no elaborate preparations were made and I used only a single coat of 2K. If I'll get to repeat the performance over a well prepared surface (as described by
Joel) then the finish will be even better and me a happy modeler. The only problem I see is that the surface of the model is bigger than the surface of a spoon and so more difficult to achieve a flawless saturation coat... to be seen.
Cheers!
Gabriel