If you are going to coat very low volumes then just spray it by hand. The automated machines just won't be worth it unless you are going to do a very large run. They are complicated, require constant attention, still require masking the board and are very expensive. To spray it by hand is a very small investment in equipment and not very difficult. A better option is to out-source the process to a coating house. Easier then dealing with hazmat, equipment purchases, etc.
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