I don’t want anyone to know that I often do things that are downright easy to do. I learned how to do these trays last year in Naples, Florida when I was doing a tag team workshop with Hayne Bayliss. Hayne does some great hand building and much more complex than I want to tackle.
Here is the process in a nutshell.
I roll out a bunch of slabs. I have a 1”thick piece of plywood the size of the tray I want to make that I place on the slab. You could have fancy petal rims on your trays. Mine are rectangular and square. I cut out the clay and soften the edges where I cut by putting a piece of newspaper over the slab and rubbing the edge thru the newspaper. The arts section or the sports sections work best. I have found the obituaries really kill the work. I then let the slabs set up on sheets of drywall. When I think the slab will hold it’s shape I take it over to my oversize piece of foam rubber and press down on it with the wooden shape. You can use a smaller piece of plywood for the center and just push down on it. Glue a handle on the plywood so you can push down and lift it out. This is the not so handy guy’s hydraulic Ram Press. I put the trays on a board and handle them in the morning. Easy peasy.