I had to use about 12 batches of concrete paper clay to cover the giant panda sculpture. That’s too much for the electric hand mixer I’ve been using, so I upgraded to a drill mixer and a 5-gallon bucket.
Upgrading to the drill and bucket, I could mix six batches of clay at one time. I still had to knead in the cement by hand. I stored the clay in a plastic bag to slow the cure, pulling out handfuls to work with. This approach allowed for about 5 hours of working time before the clay went hard on me.
I also learned sifting my Portland Cement improved the smoothness and mixed more evenly. Bakers tip!
The recipe I use for concrete paper clay is from Joni at Ultimate Paper Mache. Learn about the recipe here.