Yesterday, I spent the day laying stucco onto the top of ceramic insulation which was laid on top of the arch of my new Manabigama wood-fired kiln I am building. The stucco protects the insulation and gives the kiln a finished look.
I opted for a small galvanized pale for measuring the amount of sand, clay, perlite, mortar and portland cement for my stucco mixture, and used heavy duty rubber gloves to protect my hands from the caustic cement mixture.
Start with ten parts perlite, six parts clay, six parts sand. Secure my respirator and mix by hand in the wheel barrow. Add four parts mortar and four parts Portland Cement. Mix by hand. Add water and mix by hand. Add more water and mix by hand several times until I reach the correct consistency. Catch my breath and begin to form patties and lay them onto the arch of my new kiln. Spread out with a small trowel and smooth down every now and again.
I think it took seven wheel barrow loads to finish up with nothing to spare.
Twelve hours later, I stepped up the stairs to have dinner and turned around to look at the kiln in the light of a couple of incandescent bulbs. That's a beautiful kiln.