Signlords,
Yes, this can be made to work, though I prefer the hinged kits that are made for retrofitting. This is, however, a cheap way to make a flexible face to fit onto an existing cabinet.
We have made these as large as 6x8 and they lasted till the business closed. We stretched the fabric on a square tube frame just like in the photo and then put screws through the frame into the cabinet. Then we made oversize retainers to cover the edges.
The main problem is the frame tends to bow inward even from just hand tensioning of the fabric. We used duckbill welding clamps to grip the fabric and bend it around the square tube frame while we inserted screws. One of the fabricators solved the bowing problem with a couple of braces welded midway and perpendicular to the long dimension of the frame. To keep the braces from creating shadows, they inset them into the cabinet space about six inches using short pieces of square tube welded to the inside of the frame at 45-degree angles (I would draw this to show you but I'm not at work). Measuring carefully, they positioned the braces so they would be between, rather than in front of, vertical lamps when installed. Even with the braces, the frame structure tries to rack a little when you are tensioning the fabric, but it flattens when screwed to the cabinet. We started using screws with washers for fastening the fabric but found that using a truss head screw with no washer would work and was faster. Once in a while the screw would try to twist the fabric up. I learned to use just the right setting on the screw gun clutch, hold the fabric nice and tight, and screw as straight as possible. I always spaced the screws about 2-3 inches apart.
Obviously, the face can never achieve the same tension as a screw-tensioned or spring-tensioned system, but it did work.
We never suffered a blowout that I knew of.
This must be done with fabric made for flexible faces. Banner material will not work. It's not heavy enough and is not tear-resistant enough. It probably doesn't have the mildew resistant additives either, like Cooley fabric or Flexface fabric (Flexface is a trademark owned by Arlon unless it has changed hands).
Was it a pain in the rear to service the sign later? You dang right it was. If the vertical braces penetrating the cabinet space were not into the cabinet too deeply, so that they cleared the lamps, the frame could slide from side to side for a ways. But often the easiest way to service the sign was to just remove one whole face and lay it on the ground. The installers did not like seeing us making these frames.
I am a big fan of flexible faced signs, though they can be expensive. They can solve so many problems.
The best flexible-face signs I have seen were designed so the lamps and ballasts could be accessed from the outside without removing or loosening the fabric face. You can put ballasts in inset cubbies on the sides of the the cabinet, for example, with covers, of course. Access holes top and bottom can be made for lamp changing. If the holes are made with lips and the covers made like small pans, the holes can be waterproof (mostly
).
Brad in Kansas City
