Thanks guys. I finished painting a 10 guage steel liner that will be added to the form as well. It will run nearly the full length of the form on both sides of both the top and bottom pieces. It will add nearly 30# to the form, and it may not be necessary. I figured it would help prevent flex while under pressure. At nearly 72" long and nearly 2" wide...that would be just under 144 square inches. Even at under 100 psi, that would be about 14,000 pounds total pressure on the form. I don't want all my hard work for accuracy, squareness, or symmetry to be altered by flex, so I though it would be better to have it and not need it than it would be to need it and not have it. I will post photos of it when I am done adding it to the form.
Just waiting on the air hose, smooth on, and laminations. BTW, one can't tell from the photo, but the aluminum liner on the top has an air "insulation" space behind it that is about 3.5" (one 2x4) from the table top. I didn't use any actual insulation as it is all labelled "flamable." Also, there is a small fan on the right to circulate the air in the box to prevent hot spots. I also felt the aluminum backing and roof would help disperse the heat by conduction further preventing hot spots