Avoiding HDU warp in the sun

[signs_welly]

This was installed by the previous owner about 4 years ago before we took over this shop. That being said, I'm not sure we wouldn't have installed the same way. We don't have a full size CNC in house so the sign wasn't made by our shop but I'm assuming it is 15lb HDU painted with Matthews Paint. (Our records just say HDU.)

As you can see there is a pretty pronounced warp happening. The sign faces east in South Florida and is painted black on the back. It is not the only sign on this side of the shopping plaza that is warping but it is the most pronounced. It's 8 ft long by about 1.5ft tall and mounted to the brackets provided for all signage in the plaza.

About a year ago we did 2 other signs for this plaza - sending them out to the same machinist that did this Top Flight sign. When we installed we added a large angle bracket along the bottom of the sign - but when we went to check on it today as we were looking at this sign, we could see signs that those two may also be starting to warp. The bracket seems to be helping as it is very slight - but I don't know how long it will keep the warp at bay.

So how to keep this from happening again when remaking this sign? The only sign on this side of the plaza that wasn't warping appeared to be made of cedar and didn't have that sharp, smooth look that the client wants. All the HDU signs were showing at least some signs of warp - but this one has the most direct sun and I think that's why it's the most pronounced.

 

[Z SIGNS]

Foam on its own without some kind of support or framing is a no no. Especially if you don't paint the back as well and have a face that is dark colored.

 

[Billct2]

We usually bond HDU to something like acm to add stability unless it's getting installed flat. Or you can add an angle top & bottom. Some shops cut a groove and insert a t bar.

 

[Gino]

Without some sort of major framework incorporated in/on the back, when you have a long skinny sign and substantially carve away one side...... the piece is gonna warp. You no longer have the same tension on both sides, so you hafta manufacture it. As mentioned, I don't know how the back was handled, but it only stands to reason, if you sandwich 2 pieces of HDU around a major frame for a double sided sign, you most likely need it for the single-sided, too.

 

[Graphic Destruction]

I'm layering that sign over an aluminum internal frame every time. You gotta have something inside to keep it from warping. It also adds the structure needed to survive storms here in Florida. Even flat mount HDU always goes onto an aluminum backer to prevent warping.