Step 1: Tools and Materials
1 piece 3/8" ply-3/4" wide by 20" long,
1 piece 1/2" ply- 3/4' wide by 20" long,
1 piece 1' ply - 20"x16" (for a baseboard) ,
1 piece of unprimed 100% cotton, heavy, artist grade canvas. Primed canvas won't work! ,
Rolling pin that is at least as wide as the baseboard. you can also use a length of 2" (closet hanger) dowel if you sand the heck out of it so that your clay does not have wood marks in it.,
6- 1/2" #10 screws,
Staple gun with 3/8" staples,
The 1" ply can be bought as sub-flooring in a 4' x 4' sheet as most larger hardware stores.
Step 2: Assembly
Pre-drill the 1/4' ply strip and allow counter sinks for the screws.
Screw the 1/4" ply to the outside edges of the base board, counter sinking the screws so that the pin will roll smoothly over the top.
The other 2 strips of ply can be nestled inside the 1/4" pieces for thicker slabs.
Wedge the clay on the board (works great as a wedging table, too) and flatten out with your hands, then roll it out. Should be nice, with uniform thickness. You can use a rib tool to smooth the canvas marks off your clay.