You’ve got questions, we’ve got answers. Most everything you need to know about using Precision Board high-density urethane.
If it’s not here, give us a call at 800-845-0745 or send us an email and we’ll look into it. Your question could end up in the vault!
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Precision Board HDU is a versatile, cost-effective and eco-friendly high-density polyurethane sign material that is particularly effective for making professional-looking dimensional signs. It is a closed-cell rigid substrate that does not rot, warp or crack. Precision Board has a uniform surface with no knots and is easily cut with a CNC, laser engraver, waterjet or carving tools. It lasts indefinitely. It can be coated or textured to resemble a variety of materials, including wood, metal, stucco, brick or stone.
More info:
PBLT
PBHT
Density is the standard term for determining weight of a cubic foot of material, any material. A cubic foot is a cube that is 12″ x 12″ x 12″. Its weight is the density. The higher the density the thicker the cell wall and the tougher and heavier it is. Thicker cell walls mean it takes more pressure to crush the cell wall. Heavier means there is more material in its makeup, so it costs more. The only physical difference between a 4-pound density PB and a 60-pound density Precision Board is the thickness of the cell wall. The cell wall thickness only determines toughness and has no effect on its weatherability, solvent resistance, etc.
Precision Board is available in the following densities (click on individual densities for data sheet information): 4, 6, 8, 10, 12, 15, 18, 20, 30, 34, 40, 48, 60, 70, 75.
More info:
LINK (Material Selection Guide)
Videos:
https://www.youtube.com/watch?v=mKwMixMXFmk (Density explained in 22 seconds)
Precision Board High Density Urethane (PBLT = Precision Board Low Temp) from Coastal Enterprises is made specifically for applications of up to 200° F continuous exposure. Precision Board High Density Urethane (PBHT = Precision Board High Temp) is made specifically for applications of up 300º F continuous exposure. You can consult our Material Selection Guide to determine if your project needs PBLT or PBHT and in which density.
More info:
PBLT (LINK)
PBHT (LINK)
Material Selection Guide (LINK)
Precision Board is available in 8 standard sheet sizes with thickness ranging from ½” to 24” in ANY increment. Precision Board is available in the following sheet sizes: 20”x60”, 24”x60”, 30”x80”, 48”x60”, 4’x8’, 4’x10’, 5’x8’, 5’x10’.
More info:
LINK (Custom sheet cutting)
Videos:
LINK (sheet sizes video)
Material is made on the premises and not farmed out, so we can cut your Precision Board HDU sheet to any thickness from 1/2″ to 24″ in ANY increment.
Precision Board now has Eco-Friendly, environmental safeguarding, Green components. This state-of-the-art formula is not only easier on the planet but has also created a much tighter, finer cell structure, making it much easier to carve, prime, and paint; more chips, less dust. Carbon footprint = 3:1. Rapidly Renewable Materials = 23.9%. No VOC’s, Non-Toxic, Totally Inert, and no Carcinogens. Made in the USA.
More info:
Precision Board high-density urethane (HDU) is made of millions of tiny bubbles, or cells, that are mostly separate from each other. Since these cells are not interconnected neither moisture nor temperature can enter Precision Board. This means it does not warp or crack from water penetration.
Yes, it can. Precision Board, being a closed cell product, absorbs no moisture. It is a fairly good insulator, so temperature does not migrate into it. It has been tested from -423°F to +300°F with no degradation or breakdown. It doesn’t absorb water from high humidity, rain, snow, or ice so it does not expand or contract because of water intrusion. This means it doesn’t warp or crack and the paint lasts longer and stays brighter than on wood.
Yes it does. Virtually every material, whether it is metal, glass, wood, stone, or HDU, expands and contracts as it gets warmer and cooler. This movement, and it’s different for every material, is called Coefficient of Thermal Expansion or CTE. The CTE of Precision Board is 26 X 10-6. When an architect designs buildings, dams, houses, etc. the CTE of each different material is taken into consideration to allow for its required movement of Precision Board. Call us for how this applies to signage.
Yes. Left in the sun unpainted, Precision Board will start to discolor and turn brown in about 48 hours. Left totally unprotected Precision Board will continue to turn brown and breakdown from UV at about 1/32″ per year. This means about 1″ of deterioration every 32 years. Obviously, deterioration is not a problem, but the brown color is not pleasing. However, just under the brown surface the cell structure is unaffected. When this surface is removed it is ready for primer and paint. Keeping the painted surface looking good will assure a very long service life.
Yes. Precision Board is a closed-cell High Density Urethane (HDU), which means it keeps water out! It absorbs no moisture, and stands up to temperature extremes with no degradation or breakdown. It’s perfect for outdoor signs and displays that need to withstand rain, snow, ice, sleet and high humidity. Even signs in drier climates can benefit from Precision Board’s moisture-repelling qualities: Repeated dousing with sprinklers or exposure to moist sea air can compromise a wood sign, but HDU stands up!
More info:
LINK (weatherproof signs with HDU)
LINK (life of sign warranty)
The very best way to assure you receive top-quality high-density urethane is to always remember to ask for Precision Board by name. Accept no substitutes. Technical support is readily available. Call us toll-free at (800) 845-0745 for samples and check us out at www.precisionboard.com. We are here to help.
Videos:
https://www.youtube.com/watch?v=WG-XXGXBOFc (Why choose Coastal?)
High density urethane has been used commercially as exterior insulation starting with the Saturn S-II moon launch vehicle in 1964, and as exterior insulation on the Alaskan Pipeline in 1970, still in service. Currently, in addition to being used as insulation for homes, water heaters, refrigerators, and freezers, it is used for signage, tooling, model making, boat building, and in many other places. Urethane is very versatile and track proven. Precision Board has been manufactured by Coastal Enterprises since 1972.
More info:
LINK (History)
LINK (CW Podcast)
The density of redwood is about 26 pounds per cubic foot. The standard Precision Board density for sandblasting is 15 pounds per cubic foot. A 1″ thick 4′ x 8′ sheet of PBLT-15 weighs 40 pounds. A similar sheet of redwood weighs almost twice as much.
Precision Board may be more expensive initially on a square foot basis depending on the type of wood. However, since it comes in standard sizes of 4’x 8’, 4′ x 10′, 5’x 8′ and 5’x 10′ in thicknesses up to 24” thick, there is usually no laminating or surfacing required. The savings in laminating labor, equipment usage, and shop flow time will usually more than make up the initial cost difference.
More info:
LINK (HDU vs. wood signs)
LINK (19 Precision Board signs for price of 9 wood signs)
Yes. None of the commonly used solvents such as lacquer thinner, methylene chloride, naphtha, mineral spirits, etc. will attack Precision Board.
Coastal Enterprises works with a network of distributors across the country and in Canada who stock Precision Board HDU. You can use our online distributor directory to search for a distributor in your area or give us a call at 800-845-0745 and we’ll connect you with the closest one stocking Precision Board HDU.
More info:
LINK (Distributor Directory)
Yes. Carving HDU is almost the same as carving wood but it is much faster and easier. The same types of chisels, knives, and other surfacing tools can be used. It is easier on the carver however since it has no grain direction. Severe radius turns and angles are easier to do and the carving tools don’t have to be kept as sharp to achieve fast, clean removal. A more creative approach can be used when carving Precision Board HDU because of the ease of removal. Precision Board HDU substrates save time because they can be purchased in large, thick sheets which eliminates the need for laminating and planing.
More info:
LINK (Jumping the Shark)
LINK (Durnford gable)
LINK (hand-shaping HDU)
LINK (Rob Estes)
LINK (hand-carving HDU) ??
Video:
LINK (hand-carving playlist on YouTube)
Yes. Routing and cutting HDU is the same as wood only is much easier on the router or saw motor. Deeper passes and faster feeds are all possible because of the no grain cellular makeup. Precision Board HDU is easily cut or machined with standard cutting tools. If you need help with cutter selection, go to Onsrud’s Router Bit Search Tool and search high density urethane. CNC is an acronym for, “Computer Numerical Control.” Essentially, CNC machinery is a computer operated mechanism which precisely cuts or engraves complex shapes in HDU , metal, plastic, stone, wood, and a range of various medium types.
More info:
LINK (Router Bit Selector Guide)
LINK (Speeds and Feeds settings with Onsrud)
LINK (Speeds and Feeds settings with X-Edge)
LINK (Speeds and Feeds settings with a Techno CNC)
LINK (S+F for MultiCam)
LINK (picking a CNC router part 1, 2, 3)
Videos:
LINK (Routing/Machining Playlist on YouTube)
Yes. With the advent of the newest lasers and their ability to be finely controlled, Precision Board can be very effectively engraved and cut. In some cases, charring on the edges may occur.
More info:
LINK (Laser Engraving Page)
Videos:
LINK (Laser Engraving Playlist on YouTube)
Yes. Water jets cut by focusing a very high pressure, small diameter, stream of water. The cut is very smooth and thicknesses up to 6” thick have been accurately cut using this method. Water jet cutting is normally used to cut very large letters that won’t fit on a router table.
More info:
LINK (Waterjet settings for OMAX)
LINK (Waterjet settings for MultiCam)
LINK (Waterjet settings for Flow Waterjet)
Videos:
LINK (Waterjet Playlist on YouTube)
No. Precision Board does not soften and dissolve with heat as does styrene. Precision Board can only be cut with tools that cut wood. If it won’t cut wood, it won’t cut Precision Board.
No. Precision Board is totally reacted and inert. There is nothing inside it that is released during cutting, etc. Standard particulate dust masks and eye goggles are recommended however to keep the dust from entering the eyes, nose, or mouth. These protective devices should also be used, for the same reasons, when cutting or sanding wood, plastic, steel, or any other product.
More info:
LINK (Sustainability Facts)
LINK (Universal Laser Systems Test)
Sandblasting Precision Board is just like sandblasting a lightweight wood. Blasting pressure needs to be about 60 psi max. at the pot. You can get much closer to the work surface because of the low blasting pressure and the detail and shapes can be much subtler. Very interesting textures can be realized by using heavy grit blasting material and standing at different distances from the work piece. Since the blasting pressure is low, the grit moves slower and instead of pulverizing the surface it takes out small pieces of the background. Less pressure means a smaller, less expensive compressor can be used. Using Precision Board allows almost anyone to become their own blaster if they so desire.
More info:
https://precisionboard.com/sign-making/sandblasted-precision-board-hdu-sign/ (Sandblasting Precision Board)
LINK (time saving tip)
Verify your blasting pressure has been reduced to 50-60 psi. Consider one coat of primer or even complete priming and painting prior to mask application. Also consider using a high tack sandblast resist directly to raw Precision Board.
Yes. Precision Board HDU can be coated with a variety of spray-on metal coatings, providing for a less-expensive and lighter-weight sign that is metal for all intents and purposes.
More info:
LINK (Chrome-coating)
LINK (spraying metal onto hdu)
Videos:
LINK (metal coating playlist on YT)
Flat mounting directly to the wall is best accomplished using studs as hangers. The first step is to put the studs into the wall. Concrete nails work well in masonry walls as do galvanized nails into wood walls. After the studs have been installed the sign should be leveled and pushed back onto the studs with enough force to cause a small locating indent at each stud. Be careful not to damage the sign. Using these indents for proper hole location, drill a hole about 2 times larger in diameter than the stud. Depth of hole to be about 1/4″ deeper than attachment. Fill the holes with silicone caulking and slide the sign over the studs. Verify sign is still square, support as necessary, and let cure overnight before disturbing. Leaving the heads on the studs allows the silicone to grip the sign and keep it from being pulled off the wall during high winds. The silicone maintains a strong yet flexible attachment that allows for any wall movement. This type of installation also keeps from having to drill and repair attachment holes through the sign face.
More info:
LINK (Mounting HDU signs)
Do not attach a weight bearing screw or bolt directly into high density urethane. Because urethane has a cellular structure and doesn’t have grain, any weight bearing screw or bolt must have extra support around the threads. Hanging signs are typically hung from eye bolts that are either screwed directly into the sign or that are welded onto the supporting steel framework that is screwed into the periphery of the sign. Attaching eye bolts or weight bearing screws into urethane should be done by drilling a hole about 2 times larger in diameter than the shank of the screw and about 1/4″ deeper than length. Fill this hole with a structural 2 part epoxy, such as EP-76 and insert the eye almost flush with the surface. Excess epoxy can be smoothed around the eye with any suitable tool dipped in mineral spirits. The epoxy holds the threads of the fastener and greatly increases the holding surface around the inside of the hole. This makes the fastener able to take much more load and eliminates the loosening effects caused by expansion and contraction of the fastener.
Videos:
LINK (Eye bolt trick on YouTube)
LINK (Mounting HDU signs)
Since Precision Board is a cellular material it is not recommended to screw hardware directly into it. The hardware, being metal, will expand and contract with temperature causing it to work its way back out. If excessive tension or pressure is applied to the fastener the threads will pull out of the cellular material. The most secure way to install a fastener or hardware is to drill a hole into the Precision Board that is twice the diameter of the fastener and about 1/4” deeper than its screw length. Fill this hole with a structural epoxy, insert the fastener and let it cure. This way the threads are pulling against the hard epoxy and the epoxy is totally bonded to the inside of the hole. Check out the Precision Board Mounting and Strengthening Data Sheet.
Videos:
LINK (Eye bolt trick on YouTube)
LINK (Mounting HDU signs)
Because urethane does not have grain, it also has less beam strength than wood. Wide, unsupported, expanses need to take this into consideration. This situation can be addressed in several ways depending on the design of the sign and the unsupported expanses.
Three possibilities are:
More info:
LINK (Signs with authority)
LINK (bond plywood or aluminum to HDU)
Coastal Enterprises makes and recommends PB Bond-240 (link) and PB Fast Set (link), one-part urethane adhesives, that are specifically designed for these purposes. PB Bond and PB Fast Set are waterproof, solvent proof, plus they carve and sandblast similar to the basic substrate. PB Bond cures in six hours. PB Fast Set cures in thirty minutes. Check out the data and application sheets. Call us for free samples.
Blah blah blah.
More info:
LINK (custom bonding)
Videos:
LINK (bonded blocks on YT)
Blah blah blah.
More info:
LINK (custom bonding)
Videos:
LINK (bonded blocks on YT)
We feel it is necessary to prime Precision Board prior to painting because not all paints adhere to HDU for the long term. Coastal Enterprises makes FSC-88 WB (link) – a one component water-based primer/filler. It is applied directly to Precision Board, dries quickly, sands easily, and accepts all types of paints. Also acceptable is any other type of primer that has been developed specifically for use on HDU. When in doubt always ask the primer manufacturer before proceeding.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (blah)
Videos:
LINK (FSC-88 How to on YouTube)
Yes, Precision Board does not have grain and therefore does not have the beam strength that comes with grain. This means Precision Board can be pulled in the direction of the drying paint. All paints shrink as they dry which causes tension across the surface of the sign. The higher quality of paint the more strength this shrinkage has. Painting both sides of the sign with equal thickness of paint provides equal tension and will keep one side from drawing the other. This is especially true of dark colored, heat absorbing paints. See our Paint Tension Data Sheet.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (ten tips)
Videos:
LINK (FSC-88 How to on YouTube)
1. Sand any saw marks, heavy texture, or roughness from surface to be primed. Use 120 grit sandpaper.
2. For deep cuts or abrasions, pre-treat by spot priming with FSC-88 WB (link), or in extreme cases FSC-360 WB (link) knife grade filler. Allow to dry and lightly sand before continuing. To make FSC-88 WB a thicker consistency for use as putty, pour a small quantity on cardboard and let set until desired thickness occurs.
3. Apply liberal coat of FSC-88 WB by brush, roller, or spray gun. When applying by brush or roller, scrub in the first coat to wet out the cells. Allow to dry to tack free – about 15 minutes, recoat as soon as surface changes from gloss to flat matte. Spraying results in faster drying because of the higher solvent content and spray atomization. See FSC-88 WB Product Data Sheet for spraying details. Do not sand between coats.
4. Apply a second medium heavy coat of FSC-88 WB by brush, roller, or spray gun. Do not allow it to run. Allow to dry to tack free – about 15 minutes. When a totally smooth surface is not required, skip step 5 and go on to step 6. Do not sand second coat if proceeding to third coat.
5. If required, apply a third medium heavy coat of FSC-88 WB. Remember: All sanding must take place in the filler before getting back to the original Precision Board surface. Since Precision Board HDU is made of millions of tiny cells it is impossible to sand it smooth.
6. In areas of detail, i.e., relief cuts, vertical sides, and other hard to reach surfaces, allow the FSC-88 WB to dry a little longer. Use a brush wet with water to gently smooth out the filler. With a little practice you can use this technique to eliminate all sanding of these hard to reach areas. Let dry overnight.
7. Sand smooth with 120 grit sandpaper or 120 grit Drywall & Plaster sanding screens.
8. Lightly sand with 220 grit sandpaper. FSC-88 WB is totally dry when no balling up occurs on sandpaper. If it does, let dry until it does not occur.
9. For complete drying use a larger shop fan to blow across surface. Do not place item in direct sunlight as the FSC-88 WB might dry to quickly causing blistering in the primer.
10. Wipe with tack rag and proceed with top coat system.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (ten tips)
Videos:
LINK (FSC-88 How to on YouTube)
The quickest and safest way is to position a large shop fan to blow air across the primed piece. The air rolling over the surface creates a slight frictional heating which pulls out the solvent or water carrier that is in the primer. Turn the fan off during actual primer application so the primer can flow out before it starts to dry. Don’t place in direct sunlight as drying might occur too fast which can result in blisters.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (ten tips)
Videos:
LINK (FSC-88 How to on YouTube)
Yes. Precision Board is warrantied, in writing, against warping or cracking for the life of the sign. Installation must be adequately designed for HDU and sign properly maintained during warranty period. Contact us for your copy of warranty.
More info:
LINK (Life of Sign Warranty)
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Remember that Precision Board does not absorb anything. This means that all drying takes place from the outside in, which takes much longer than on wood, or other absorbing materials. Typically, after drying overnight it is ready for finish sanding. However, the primer/filler is totally dry only when it can be sanded without any balling up on the sandpaper. If balling occurs, stop and let it dry longer. This method of testing is true for water or solvent based primers. Painting over primer that is not completely dry will result in later blistering when the sign is installed. Even after complete primer drying, we recommend placing a large shop fan to blow across item for 2 hours minimum prior to painting. See our FSC-88 WB training video at www.precisionboard.com or call us for a free cd.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (ten tips)
Videos:
LINK (FSC-88 How to on YouTube)
Yes. Priming makes it easier for a medium tack sandblast resist to adhere to the surface of Precision Board. Leaving the mask in place after blasting and using it as a paint mask during priming and painting of the blasted area also saves time. Important: Always roll out primer and paint evenly as overlapped areas will result in uneven blasting. Be sure to use the proper sandblast stencil for primed HDU.
More info:
LINK (Priming Tips from the Experts)
LINK (DYK: Priming HDU)
LINK (ten tips)
Videos:
LINK (FSC-88 How to on YouTube)
Since Precision Board HDU does not have a grain structure naturally, it must be simulated into the surface. The grain effect can be accomplished by coating the routed background surface with TSF-45 (link) texture material or PB Hard Coat (link) (both products made by Coastal Enterprises) and combing the grain in with a hair comb, etc. If carving, a wire brush can be used directly on the Precision Board. When sandblasting, a frame with wires stretched over it can be easily made and placed over the sign and blasted through. The wires redirect the sand which creates a very realistic grain effect. Call us for specific details.
More info:
LINK (Using Rapid Texture)
LINK (Faux wood signs Quinter)
LINK (Faux wood signs Quinter 2)
Videos:
LINK (recreate cedar signs with hdu)
LINK (faux wood grain sign)
