MDO Plywood Sign
I'm building a plywood sign for outdoor use that I am hoping will last for a few years. I have a 4x8 sheet of 3/4" MDO plywood (2 side good) and MDO plywood letters I will be using for the sign.
The sign will be about 7' wide and I'm worried about warping. I'm looking for ideas to help with this. The sign will be attached to 6x6 posts, I'm thinking about routing out a channel in the 6x6 that I can insert and glue the sides of the sign into and then use some sort of stringer that would run along the top and bottom of the sign and attach to the 6x6's. I'm thinking if I glue and nail the top and bottom stringers to the plywood, it may help with warping.
Also, I have another sheet of 3/4" MDO (but its only 1 side good). I think it may be overkill, but I could glue the two sheets together (so I have the two good sides facing out). This would give me 8 ply's, may help with the warping, but I'll have a sign that weighs a ton.
However, I'm not a seasoned woodworker and am looking for input.
Thanks in advance!