I apologize if this has been covered before. Can I have everyone's best suggestions how to get clean lines masking dope? I just trimmed the blue on this sterling Cherokee, and I got these jagged lines, not a nice clean break. I used professional automotive masking tape. When I pulled off the masking tape off the dope almost became a film. I let the dope dry about 6 hours after brushing. Thank you

  Hi Fred;
     The problem you are dealing with is because you are brush painting the model.  After you put your base coat down and it is thoroughly dry, wipe it down with some Windex or other mild cleaner and wipe it off again with a clean dry cloth afterwards. Mask off your area to be painted, and then carefully and lightly brush a thin coat of clear with a small brush right on the tape line. Keep brush strokes to a minimum because the clear will soften the base coat. Let that dry thoroughly and then brush on your trim color, again being careful with brush strokes at the tape line. As soon as the dope seems dry, try pulling up the tape. The clear should seal the tape line and break cleanly. Pull the tape back over itself as you pull it up, don't pull up at a 90 degree angle. This helps with a kind of shearing action to the paint. There may be a slight ridge at the color separation, but let the paint dry for a day, then you can sometimes scrape the edge off with the edge of an old gift card or similar item. Spraying works a lot better but the paint can also creep under the tape, and the same procedure can work with spraying also. A good clean surface helps and right before you paint, run your finger along the tape edge also.
   Good luck and have fun,
    Dan McEntee