I'm building a really nice firewood box for a long time client of mine. The exterior of the box is a frame and raised panel box made out of sapele and it is made to match some existing cabinetry that I made previously for the clients' great room and during the winter/cooler months it will reside next to the fireplace. It is tapered from the back height down to approx 16" height of the front panel assembly. It has a handcarved initial mounted on the back right below the "alamo" shaped crest rail. On the crest rail, on the front panel, and both side bottom panels will be added some shell and acanthus carvings that I sourced from Pearlworks, the same as on the surrounding cabinetry. Everything is going according to plan except for one thing, actually five things. I ordered hand hammered copper sheeting from a copper shop in Kentucky cut to size. This stuff is fairly thick, think about 1/32" of better and somewhat rigid. Getting it to lay flat is the problem it has bulges from the hammering. I'm using #12 copper rivets from Tandy Leather to try and tack it down. Clinching the rivits on the back of the plywood liners that fit inside of the sapele paneled frame will hold it down securely but it's still uneven in areas and I don't want to machine gun rivets all over the surface. Once the copper is clinched to the plywood substrate, can it be hammered to flatten it out? Anyone ever dealt with this before?