"He who marches out of step hears another drum." ~ Ken Kesey
I don't know what you mean by a bbc dryer, but I did WB DC for 3 years with a 6 foot electric conveyor dryer and manual printing. You can do it, but you'll have to mess around with dryer settings and do test washings. Big numbers cause eventual stencil breakdown. I do enough of it to have converted over to Diazo for everything, but for quite a while I used a pure photopolymer with a temporary hardener. It worked okay for short runs.If you wanna jump in whole hog, get a gas dryer. Otherwise you'll be walking a tightrope balancing temps, dwell, and ambient conditions. I still do it nearly everyday, but eventually I hope to upgrade my equipment. My auto has helped, but the dryer is a bottleneck. If you intend to be a high volume DC shop you'll have to drop some coin.Do some experimenting off schedule. Don't sell a big job thinking you can learn while doing actual $$ work. It might do okay and it might just bite you. Just my opinion. All the Manufacturers offer sample kits. Jump on in, the WATERbase is fine! Like my grandpa used to say, "It'll learn ya."And welcome to the forum!
Here, crooked, BBC dryers.http://bbcind.com/product-category/screen-print/conveyor-dryers/ It will, of course, depend on which BBC dryer he has, but we already do know that it doesn't have forced air.At any sort of real production level, forced air will help bring a consistency to the results.As pointed out, at the least, forced air really, really helps with waterbased inks help remove the vapor, remembering that WB inks "dry" while plastisol "cures"