When it comes to substrates, sign makers have never had more options. There are dozens of products available for use as sign panels, faces and graphics. Many are prefinished materials that are ready for paint or vinyl; some can be direct printed on flatbed inkjet printer. Others are intended for cutting and carving for dimensional graphics.
You also have multiple brands to choose from in almost every sign substrate that’s available. The characteristics and quality varies from brand to brand—in finish, defects and even consistency. Don’t assume that all brands are equal.
Here’s a quick rundown of commonly used substrates by category. To learn more about specific brands, visit the manufacturer’s website. Your sign supplier should be able to provide additional information about the products they carry, too.
Sock Drawer: Overlaid plywood with ½-in. acrylic letters and carved HDU graphic. Sean Beauchamp, Southpaw Signs, Oceano, California; Design by Jimmy Aproberts
Event Center: CNC-cut PVC graphics on an ACM panel; Lois Wellner, Signery2, Hamilton, Ohio
You’ll find a list of sources for all these materials at the end. Note that these are 2013 approximate prices, based on 4-by-8-ft. panels. Prices will vary regionally.
MDO: Medium density overlaid plywood was for years the most common sign substrate. It is a sheet of plywood with a wood fiber veneer laminated to one or both sides. Double-sided MDO is especially stable because it eliminates the expansion/contraction difference that is caused when one side does not have the wood fiber veneer. Single faced ½-in., about $1.50psf; Double-faced about $1.70.
Laminated plywood: You can get quality plywood panels that are laminated with vinyl or aluminum faces, ready for graphics or cutting. These materials come in several thicknesses. Prices vary depending on laminate.
MDF: Medium density fiberboard is easy to machine, thick, smooth and inexpensive. Some brands require extra finishing attention, because the corners must be rounded and carefully finished to prevent moisture from reaching the substrate, causing it to blister and swell. Extira Treated Exterior Panels are an MDF product that is not affected by moisture. ¾-in. MDF starts at about $2.00psf
Cedar and redwood panels: When it comes to wood, nothing quite matches the beauty of the real thing. You have your choice of redwood and cedar panels that are laminated and ready to sandblast, carve or rout. Laminated 1 ¾-in. western red cedar panels: about $25psf
Aluminum: Aluminum sheet is another standard for sign work. It’s available prefinished in a variety of colors, and in several thicknesses. It needs supported to keep it flat. Don’t go too thin on large panels or it may appear wavy. Watch out, too, for expansion between fasteners, which can result in unsightly buckling. White 0.04 aluminum: $1.75psf
ACM: Aluminum composite materials have aluminum faces over a core of solid or corrugated plastic, or corrugated aluminum. It comes in several thicknesses, and the thickness of the aluminum faces varies with the brand. These panels are rigid and stable, and can be fabricated into cans and shapes. They come in many colors and finishes. White 3mm ACM starts at about $2.25psf.
PVC: This rigid plastic sheet comes in several thicknesses and finishes. It can be used indoors or out, depending on the PVC board and the application. Fungus can be a problem on unpainted PVC board outdoors in certain climates, but painting can resolve this. Note that painting PVC dark colors will increase expansion and contraction. White 3mm PVC: about 75 cents psf.
Corrugated plastic: For promotional signage, corrugated plastic is a leading choice. It can be used outdoors, is low cost and comes in several thicknesses and colors. Eco-friendly biodegradable and fire-resistant versions are also available. White 4mm corrugated plastic: about 40 cents psf.
Acrylic sheet: You have plenty of colors of acrylic sheet to choose from, and several thicknesses, as well. Rigid and durable, it’s available translucent or opaque, and has a reputation as a dependable substrate option. White acrylic sheet, 3/16-in.: about $3.50psf.
Foam core panels: There are several families of foam boards to choose from, depending on the qualities you need for the task. The foam core may be sandwiched between rigid faces of plastic, paper, wood fiber or even aluminum. The type of foam used for the core varies from brand to brand, and biodegradable boards are available. It is available in white or black, and with white or black cores in some cases. Rigidity varies, and some of these boards offer exterior durability. Prices vary widely, depending on product.
HDU: High density urethane board arrived as an alternative to wood panels for dimensional graphics. Rigid and durable, it comes in a variety of densities and thicknesses. 18-pound HDU board is roughly similar in density to redwood or cedar, and higher densities are more dense and harder. 18-pound density HDU, 1½-in. thick: about $10.50psf
Polycarbonate sheet: Another choice for flat plastic sheet is polycarbonate, which is more impact resistant than acrylic. It tends to yellow over time from exposure to UV light. White polycarbonate sheet, 3/16-in.: about $4.50psf.
There are some unique substrates out there that don’t fit into the common categories, yet offer special characteristics for sign work. They can help you meet a special need, hold up in a harsh setting or just save you time.
“It pays to learn what substrates are out there,” says Ryan Bisso, CSR at Grimco’s Chicago, Illinois, offices, “because there are a lot of great substrate products. Two quick examples: Ultra Aluminum [www.ultraboard.com] is a foam core panel that comes with an anodized aluminum face in brushed or
Piedmont Care: Sandblasted western red cedar, finished with Ronan AquaCote enamels and installed using King Klips cleats so that no hardware was visible. Scooter Marriner, Coyote Signs, Oakland, California
Beachcomber Bill's: CNC-cut HDU board with hand-carved details. Sean Beauchamp, Southpaw Signs, Oceano, California
polished gold or chrome finishes. It’s easy to use and looks great. Ultra Mount Peel N' Stick [www.ultraboard.com] is a foam board with adhesive on one side. You just pull off the liner and apply your print.”
Here are a few other products you’ll want to know about:
King ColorCore is a high density polyethylene sheet with a core of contrasting color, which makes it ideal for routed signage. No finishing is required, and it’s durable for outdoor and marine applications.
King Plastic Corp.
Fiberglass panels deliver strength and outdoor performance. It’s UV and chemical resistant. It’s available in solid sheets, and with a plywood or fluted plastic core.
American Fiber Technologies
SingCore Honeycomb Panels are a relative newcomer to the sign market, having been first marketed as a display and building panel. It uses torsion box construction—two faces separated by a web or honeycomb structure—which results in a thicker panel. It’s similar to the way hollow doors are made. Strong, light and stable, these panels require minimal support. Small signs could even project blade-style from a single post.
Corrugated paper panels are designed for indoor graphic displays and are printable. They can be recycled, and some are even made from recycled paper, which is an important feature in many applications.
Plan for expansion and contraction
Many substrates expand when heated by sunlight then contract in the cold. If fasteners don’t allow for this, the substrate may buckle slightly between fasteners when warm, which looks bad. The repeated expansion/contraction can even cause some substrates to fail, cracking at the fasteners. The solution is to drill holes that are larger than the fastener, and not completely tightening the fastener. If the substrate is held by a frame, leave space on all sides for the material to grow and shrink. The manufacturer or your supplier should be able to provide specs on the amount of expansion you can expect.
Letters, graphics and panels are all CNC-cut PVC board, designed and produced with ArtCam Pro software, and painted with Matthews Acrylic Urethane. Mike Sheehan, Classic Design & Manufacturing, Pensacola, Florida
Allwood Sign Blanks
Himes & Starr Redwood
3A Composites USA
Mitsubishi Plastic Composites America
Nudo United Industries
3A Composites USA
3A Composites USA
Gilman Brothers United Industries