Apologies for butting into a thread that is exploring different options. Options are always good -- as is any discussion that explores them. In this case though, at least for glass plate coating, the answer is dead easy, dirt cheap, and absolutely reliable. http://www.thelightfarm.com/cgi-bin/...tent=03Nov2011
The emulsion flows and sets along all edges of the plates. To that effect, it works likes Martin's technique of submerging the plates, but without the waste and mess. Also, it gives very even coatings -- something that is hard (or impossible) to achieve if the plates are moved at all between the pour and set-up.
I've been coating film every other day for quite a while now. That one is a little more difficult, in that it takes some (low tech) equipment and practice, but it's very doable. I've got a lot (probably way too much) about it on The Light Farm, but here's some info on having a very good tool made. http://www.thelightfarm.com/cgi-bin/...tent=06Jan2012
Also, PE's 5-in emulsion blade is very good for film coating, but it's not being sold anymore. I don't know his plans for it, but perhaps more are in the works. He talks about it like it is (is going to be?) a readily available tool.