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Metal Fabrication

Projecting Signs

Better tools and designs permit better, safer installations

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The fabulous 50s. I hesitate to admit that I still remember the era of sock-hops, saddle shoes and Elvis. In those days, "sign hangers" really were sign hangers. When the hanging sign was king, stiff-arms and guy cables (Fig. 1) dominated city streets. But now the king is dead — and most of the old signs are rusted hulks. In fact, I can’t walk beneath one of these dinosaurs without looking up to see whether a transformer is ready to fall through its rusted bottom onto my head.

Hanging out

You might get the impression from inspecting these old structures that the sign people of yesteryear were a pretty haphazard lot. Actually, however, the old-style, hanging sign was a practical necessity for two related reasons. The first reason is that old buildings are much more substantial than their modern counterparts. If you’ve purchased a new house lately, you’re well aware that they really don’t build them like they used to. I’ve installed signs on older building walls that were as thick as fortresses. Some had exterior surfaces of slab marble or granite with alternating brick and block courses behind them.

The second practical reason for the old "hangers" was the primitive state of tool technology at the time. The normal method of "drilling" through thick masonry walls back then was a hand-held "star drill." This is essentially a large chisel with a special tip. You drove a star drill through the wall with a sledgehammer. Not surprisingly, this encouraged installers to devise a mounting method that didn’t require complete penetration.

The traditional, hanger method addressed these conditions by employing a stiff arm and guy cables anchored to the wall with lag bolts and expanding lead shields. These required only 4-6-in. deep mounting holes (much to the relief of the sledgehammering installer). The ability of hanging signs to swing in the wind was a critical aspect of this method. Because the sign’s ability to swing reduced wind load significantly, the old method worked quite well. However, if the sign could not swing, this method would be inadequate.

The real McCoy

I’ve never considered the old-style "hangers" to be true projecting signs. They might appear to "project" from the building surface; however, the sign is actually suspended from above. A genuine, projecting sign incorporates a heavy, integral, steel frame and mounting bolts or steel supports that completely penetrate the building wall. These "through bolts" or supports must be attached to heavy, horizontal, steel braces on the inside wall surface (Fig. 2) to enable the sign to resist wind force. Fig. 3 shows a large, projecting sign that overhangs a public sidewalk in a busy downtown area.

Thanks to thinner wall construction and improved power tools, sign erectors can usually attach projecting signs with relative ease. True projecting signs represent a substantial improvement over the old hangers for two reasons:

* First, they are completely stable and do not require flexible electrical feeds or retainer bolts to prevent them from "traveling" back and forth along the stiff arm.

* Second, real projecting signs have a much cleaner appearance — without the rusty guy cables and turnbuckles.

When people talk about "the good, old days," they tend to forget these things.

Some projecting signs (Figs.4 and 5) are hybrids. They aren’t suspended from a stiff arm, nor are they attached with through bolts. If the installer hasn’t penetrated the wall and used adequate internal bracing, he must attach guy cables or steel braces between the wall surface and the projecting end (street side) of the sign. This type of installation is more typical of signs installed prior to 1970.

Because of wind loading factors, it’s uncommon for projecting (non-hanging) signs to extend more than 6 ft. from a building’s surface. Larger signs with greater projection commonly include a steel weldment (a heavy, fabricated steel structure) that is bolted to the sign cabinet on the side that abuts the building wall. This weldment provides secure attachment for the sign cabinet and forms a sturdy, structural member that can be attached to the wall with large-diameter, high-strength bolts. Given the substantial wind force on this type of sign, a heavy structure is required on both sides of the wall.

Getting Creative

Not all projecting signs are attached to buildings. A common type of free-standing sign is the pole-projecting sign (Fig. 6). This type of sign (also called a "flag sign") offers the advantage of placing the pole in a position where it won’t be an obstruction. For example, if a merchant has limited space between the front of his building and the street, he can install a pole-projecting sign with the pole close to his building, permitting vehicles to pass or park in the area below the sign.

Like signs attached to buildings, the supporting structures for pole-projecting signs must be heavy-duty. Old-style, pole-projecting signs (Fig. 7) compensate for inadequate pole structure by employing the same type of guy cable arrangement used on the old hangers. Contemporary signs, however, employ two common methods for additional support without stiff-arms or cables:

The first method is to use a square or rectangular steel pole with reinforced steel-plate "windows" fabricated into the side where the sign attaches (Fig. 8). This method requires full-penetration welding, and the pole is typically fabricated in the shop rather than the field. Receiving nuts are welded to these reinforced window plates to simplify installation.

A second method is to use horizontal, round steel pipes that penetrate the vertical, square or round pole (Fig. 9). The fabricator cuts matching holes through the opposite walls of the pole, sleeves the horizontal pipes through and continuously welds these at the exposed circular joints. The sign cabinet incorporates matching horizontal pipes that are one size larger than the pipes welded to the pole. Installers hoist the sign and slide it over the smaller diameter pipes. Then the sign is welded in place around the sleeve joints. The critical factor here is that the horizontal pipes must penetrate both walls of the vertical pole. Simply "butt-welding" pipes to the exterior wall of the pole would not be suitable for supporting this type of sign.

If a pole-projecting sign is particularly large or heavy, a special weldment may be incorporated where the sign attaches, and a second pole may also be required. Regardless of the mounting method used, proper engineering is essential for any large, projecting sign. This is definitely not the place for guesswork.

Creative projections

The versatility of projecting signs encourages many creative uses — not all of them expressly legal. One favorite technique is to install the concrete footer of a pole-projecting sign as close to the street as permitted by the municipal code. If the sign pole’s base plate is adaptable, signs that originally projected away from the street are sometimes discovered to have mysteriously turned 180°. This violates local set-back regulations, but significantly improves the sign’s visibility. It’s the kind of temptation that certain sign users find irresistible.

Fig. 10 shows another time-honored practice. If projecting signs are prohibited by the local code, some users will add a projection to their building facade first, then install a sign on it later. Technically, this circumvents the local code — but many municipalities are wise to the practice. Based on my travels around the country, sign companies are quite resourceful in exploiting such regulatory loopholes. Where installation techniques are concerned, however, you’re well-advised to walk the straight and narrow path.

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