Maybe I have the term wrong but according to Jim Ryan's instructions . . .
Found here
http://home.fuse.net/ryan/silkspan.htm
Quote step 8: "Mixing Filler: To fill the weave preparatory to painting, mix regular talcum powder into your thinned dope until you have a slurry. You'll have to acquire a feel for how much to use; too little and it doesn't fill very well and is harder to sand; too much, and the filler will be porous and won't take a smooth paint surface. The right mixture has the consistency of watery wallpaper paste. "
As I don't know what a slurry is I don't know how thick that is. And I have never worked with wallpaper paste so I have no idea how thick that is.
I am concerned as I dont want to use too little and not be able to sand, and I dont want a big mess from it being too thick. As I am using butyrate dope I need this mixture to stop the tautening of the silkspan, as well as stop any cracking.
So how thick is wallpaper paste and a slurry?