The first medium I ever used for screenprinting and the only water based medium I've ever used that I like was honey. Easy to mix, gives a nice dark line, good for trace lines. But not very easy to adjust in terms of paint thickness. Also, it is a non-drier and that can be problematic.
I've mostly use Reusche D882 Oil medium.
I've also used D662 and that works fine. I did not like the D175.
Oil has several advantages over any water based media. It dries to a hard smooth texture which you can scratch into to fix lines. Also, you can treat it like scratchboard and scratch white lines into it.
Also, with oil you can do a water matt over it after the oil is dried. It is tricky and I rarely do this but have done it successfully in the past.
Thank you so much...do you have a site where I could see your work? Your avitar alone is pretty great. I've only screened once and that was with assistance on a restoration piece (which can be seen on my site http://www.BlackwellsGlass.com). I'm more an illustrator than a painter and so with screening see so much potential for future works more akin to my style...YEAY!!!
Well Darn, I just contacted Sunshine and they no longer carry Reusche D882 or D662Oil medium....though they do still stock D175. What luck huh? May I ask where you buy your stuff? I've called all the local art suppliers in Boston and none seem to know what I'm talking about.
As happens sometimes, it's a bit long and rambling and it's more about the thermal screen printing process than about the actual screening of the paint on the glass, but it may be of interest nonetheless.