First of all, do not use kapton tape! It tends to cause a dewetting effect around the tape. A call to Humiseal will explain why.
There's not really a blanket answer to your question....
Removing cured liquid mask can often result in a fillet effect with thicker coatings. You'll end up with a crater around the masked area after mask removal.
Liquid mask generally does not work well in small amounts. In other words, if you are masking an area with liquid mask, make it thick so it separates from the coating and is easy to grab for removal. A thin layer of mask can easily become part of the coating layer.
Humiseal has some tapes available that work fairly well, but a cheaper alternative is to use masking tape used in autobody painting. You may want to test for ESD safety when choosing the tape.
Preformed caps are great for higher volume production. However, they can only be used if the coating is sprayed.
In my experience, when dipping a board for coating, the only way to go is liquid mask. If the tape is not completely sealed to the PCB, then capillary action will pull the coating under the tape. It happens instantly.
Also, in some cases, a stencil works well. We recently had an order for a small # of boards that required a high voltage area to be coated. I cut out a quick stencil out of cardboard and sprayed the area. Worked perfectly and cost virtually nothing.
There is a variety of factors to determine what's best. Unfortunately, part of that involves doing it the wrong way the first time! You'll generally need to experiment a bit for each situation.
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