For starters stay away from SPEED BALL.. I made that mistake 3 weeks ago and learned fast. ended up buying ulano qt-5 emulsion and some aluminum frames from Victory Factory Here in NY... The screen were horrible to clean.. emulsion stayed locked even after under exposing..
Oh and get yourself the stoufer exposure thingy it helps with finding the right exposure for you emulsion..
I also built my own exposure unit with the help of my husband..