I prefer 5/8" plywood (finished on one side). If properly
mounted to the wall (3" screws and anchors), there is no
warping. Pre-drill the boards and set your anchors before
hanging the mural. When doing the painting, prime the
surface that you are working on and the edges as well.
Gesso works better than regular wallboard primer in terms
of the color of the paint not appearing dull. I typically
semi-gloss interior latex for inside work. The edges of the
boards should be finished with the paint also if they are
going to show.
Enlist the help of the maintenance staff and then give them
credit for their help.
> We want to do a mural way up over a large indoor entry
> way. Since I am unwilling to put my students (or myself
> !) on scaffolding, I was considering having masonite
> panels cut to fill the space (may take 4 of those large
> ones I guess?) These then could be painted before they
> were installed. I know they warp, and have in the past
> gessoed a big X on the back to prevent this...Is this how
> you all would approach a mural to be over 10 feet from
> the ground at its lowest point? Any ideas are
> appreciated. Thank you so much.