Conformal Coating Room

We are in the process of revamping our conformal coating room. Presently, we have a C-740 Nordson Asymtek coating machine that sprays most of our boards with Dow Corning 2577. We are spending a lot of time masking boards and are thinking of upgrading the machine with dual dispensers (SC-300 and SC-400). In the same room, we have a spray gun area closed off with a curtain, this area coats the boards with Humiseal 1A33 and 1B31. Should we separate the silicone and acrylic/urethane in different rooms?

Another area of concern, we bake all of our boards at 55C, but I noticed that the recommended specs for Humiseal is 76C. A few people are concerned that the higher temps might damage displays/fiber optics. Should the Dow Corning cure at room temp? If so, will the acrylic/urethane contaminate the boards? I was thinking of creating 2 rooms, one for the silicone, and one for the acrylic/urethane. The silicone could cure at room temp and the acrylic and urethane could bake in the oven at a higher temp.

All in all, I'm trying to utilize our existing equipment and redesign an efficient controlled process. Does anyone have any recommendations, tips, or advice? Thanks in advance!

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