I have just finished carving the attached design on a piece of 2", 15# HDU...Turned out Great !!
Finished thickness ended up being an average of around 1.5", with the thinnest wingtips at around an inch. Project will be fully painted and is for exterior use. (This is my first LARGE HDU sign, so its a little different than what Im used to). This is to be mounted flat against a homes vinyl siding. I usually do 24" or so sign, so this is a big step to try a larger project for a change.

Questions:
1. Backing board ?? - There is a lot of conflict out there. MDO, PVC, Aluminum, regular marine ply... What are your thoughts ?? (I do understand that MDO edges need attention and how to "post" into the HDU with epoxy, etc). Concerned for stability of design and of course dont want this to warp & crack in 2 years.

2. Mounting to the vinyl siding. Ive looked at french cleats at the top with a couple anchors towards the bottom, posting through in several locations or tension mounting between angled hangers. My concern, of course, is the stability of the narrow protrusion of the wings & banner. Any ideas, techniques or long-term success stories would be greatly appreciated.

freedom sizes.jpg
Thanks so much...I haven't posted much here, but the help I've received has been great !!

Brad