Here you can see how I folded the canvas wrapped around to the back. The dark area is where the glue was applied. The folded over canvas adds some thickness to the edges so I'll try trimming the canvas flush with unfinished ones. Here is a shot of the texture of the canvas after final gesso has been applied. Very much like the Ray Mar panel surface so I'm happy.The Masonite I purchased was Tempered Masonite as opposed to Un-Tempered Masonite. If you can find untempered masonite buy it and use that. Tempered masonite is impregnated with oils so it stands up to outdoor usage. People worry about the oil coating getting to the paint. The bulk of the oil is really on the surface so sanding takes off most of the oil coating. I am covering it with the glue and the canvas and the final coats of gesso so the oil in the board is not going to effect the painting at all, but, get untempered masonite in case you decide to paint on the masonite without covering your panel with canvas. I plan on covering all of my boards with canvas so tempered masonite was ok for my purpose.
I used a table saw to cut my boards but you can do it with a metal ruler and an exacto knife with new blades, just takes longer to cut. If you don't have a table saw find someone who does because it's so much easier. These are big panels so get the thicker masonite of you plan on doing larger sizes. When I glued the canvas to the front the board warped (bowed) some but after applying the glue to the backside it straightened out completely.
Larry Seilor and Marc Hanson have written great articles on WC for making panels and I think you will enjoy reading both processes. I could get in more detail on this but their articles cover it all completely but this is basically how I did it and you can do them as you like. It's not rocket science, don't make a big thing out of it.....
Cut tempered or untempered masonite to size.
Glue canvas to panel using Acylic Medium, Gel or Mod Podge.
Prime with gesso front (and back if you like).
Buy an ice cream with the money you are saving and Get Painting!