When masking how do you cut around the masked area with out damaging the already painted area? When I’ve tried before I make cut marks into the paint.
Generally, you want to avoid this practice if at all possible. Usually, you want to cut your mask then apply it to the model. So folks use you technique when masking canopies, but I have never had much luck with it. If you must do it however, use a brand new blade and very minimal pressure.
To expand on cbaltrin’s excellent advice, I’ve only had luck cutting the tape when it needs to be cut where there is a seam or panel line to hide the cut (for example, the frames on a canopy). Along with the new, sharp blade and light pressure, cut at an angle, into the frame so that the cut line on the plastic will look like the seperation line between the metal and glass, if it shows at all.
In areas where there are no seams or panel lines, lay your tape down and draw your cuts with a fine sharpened pencil. Then remove the tape carefully and lay it down on a cutting mat to cut your line, again with a fresh, sharp exacto blade.
Before removing the tape from the model after you drew your lines, you may need to use the pencil to make reference marks on your model so you get it back in the same exact spot again. You can use a hole punch or cut small holes in the tape before you apply it, then trace the holes on the model. When you put the tape back on, line these holes back up with your marks, then cover them with small bits of tape before you paint.
However, if you can avoid all that and just lay down thin lines of tape in the pattern you desire, it may be easier. You can fill in between those lines with larger pieces of tape to fill in the gaps.