Hi Rehd:

Regarding the "bleeding" under the tape...it's all in the type of tape and how well you burnish (rub) the edge. Now this is assuming the surface is really smooth to begin with. Forget paper masking type tapes. In the sign biz we buy a very thin bright 1/4" tape for pulling long straight lines. It has some give in it so you can make fairly gentle bends in your lines. If you don't have a sign shop or supply close to you to get some line tape the next best thing is Scotch Brand or similar "magic tape"...this isn't the shiny stuff, more of a mat finish which when burnished down goes quite transparent. It's about 1/2 wide so it can't pull as tight a curve as the narrower tape but will still give a nice razor sharp edge with no bleed. If you are using a wide brush with an unsteady hand you can always place some wider "el-cheapo" masking tape on top of this so that there is still some of the "good" tape showing a bit at the edge.

Regarding the tape pulling up paint...this is usually due to one of two things and sometimes both. The surface wasn't prepped or sanded properly and/or the top coat is not compatible with the coat underneath. Best example is painting a latex right over a gloss oil base paint. Sometimes adhesion problems happen when the coat underneath hasn't fully cured yet...it sometimes takes weeks even though it feels dry to the touch!

Best wishes on pulling those fine lines...Doug