Sandblasting Precision Board HDU: Tips from SignCraft Readers

Sandblasting Precision Board HDU can allow for many more interesting and subtle textures than a wood sign.  In addition to sandblasting much faster than wood, it allows the sandblaster to move much closer to the surface.  Because of the low blasting pressure, the detail and shapes can be much more subtle.  Dave Showalter of David Design and Danny Dean of Dynamic Signs Design recently wrote into SignCraft Magazine with their tips for sandblasting HDU.  They also sent us photos of some of their signs, fabricated from Precision Board high-density urethane foam, manufactured by Coastal Enterprises.

Danny Dean, Dynamic Signs Design, Rice Lake, Wisconsin:

Sandblasted effects on HDU
“I like to mix textures when sandblasting a high density urethane sign. I may blast the background through the Grain-Fraim [] to get a wood grain effect, then blast the border or a panel directly to get a stucco or stone effect.
I like the contrast of the stucco finish against the woodgrain.
I sometimes make a template with a slot in it that lets me blast faux mortar joints for a brick or stone look. You can create a stone effect that way by monkeying around with the sandblast to get an irregular surface.”

David Showalter, David Design, Bryan, Ohio:

Make sandblasted HDU woodgrain look even more realistic
“I often sandblast high-density urethane through the Grain-Fraim to simulate sandblasted woodgrain backgrounds. Over the years, I’ve found that a couple of tweaks during the blasting process that make the effect look even more realistic.
First, my sandblaster does an initial blast through the Grain Fraim. Next, he moves the Grain Fraim about an eighth of an inch up or down and continues blasting. This really creates a great look.
Finally, we remove the Grain-Fraim and continue blasting. It deepens everything. It just adds to the effect and makes it look more realistic.”


Both of these gentlemen used Precision Board HDU in their sandblasting tips for SignCraft Magazine.  You can check out our SignCraft Magazine page on the website HERE to see all the articles where Precision Board and Companion Products (adhesives, primers & fillers, textures & coatings) from Coastal Enterprises are mentioned.

We offer more detailed tips on sandblasting Precision Board high-density urethane HERE as well as in this blog post from Kendal Signs in Florida who not only replaced several cedar signs with Precision Board HDU, but also sandblasted them and let us in on their process.

Not sandblasting, but still want to get that wood grain effect on Precision Board?  Coastal Enterprises’ TSF-45 Texture Coating is perfect for adding grain to HDU.  Call us for samples!

Coastal Enterprises manufactures Precision Board HDU, a versatile, cost-effective and eco-friendly urethane sign material that is particularly effective for making professional-looking indoor and outdoor dimensional signs.  It is a closed-cell rigid substrate that does not rot, warp or crack.  You can request free samplesget a quote or sign up for periodic newsletters packed with helpful information.

Sandblasted Precision Board HDU City Signs

Kendal Signs has fabricated about fifteen signs for the City of Cocoa, Florida over the last several years.  What originally started as cedar signs are now being replaced with Precision Board HDU after the harsh Florida weather damaged them.  In this blog, Anna Johnson with Kendal Signs talks us through routing and sandblasting PBLT-15 Precision Board HDU and then attaching aluminum to the back for support due to the large size of the signs.

kendal signs

Anna used 1 ½” thick 15lb Precision Board to create two signs for the City of Cocoa.  Kendal Signs designed the original signs for the city using cedar planks per the client’s request.

“It has been a few years since those signs were installed and they have been damaged by hurricanes and the harsh Florida climate, so we are replacing the wood signs with HDU,” says Johnson.  She adds, “with Precision Board, you don’t have to worry about rotting.”

With the dimensions on the two signs being 5’10” wide by 7’6” tall and requiring multiple pieces of material, they had to be glued together and backed with .125 aluminum for added support.  Additionally, the overall sign is 17’ above grade.

Anna tells us, “we used an expanding urethane adhesive for the seam and clamped the pieces together.”  She adds, “the aluminum was then epoxied onto the back of the sign.”

Powder coated metal poles were specced because of the weather and the material’s ability to keep moisture out of the sign.  Z-brackets were put on the back and U-bolts installed onto the back of the sign.  They then mounted the sign to the poles.

The signs were then masked off for sandblasting followed by a topcoat of Mathews Paint.

“We used a sandblast mask and applied it to the HDU,” Johnson says.  “Then we put a wire grate over it to give it a wood grain look.”

They operated the sandblasting machine at 80 psi and took about 5-10 minutes per sign.

kendal signs

Anna likes using Precision Board HDU because she can get a nice finish on it and doesn’t have to deal with weather-related issues like rotting or warping.  “It’s not like some boards that are more porous and chip away.  It’s cleaner.”  She adds, “the quality is better, so it makes for a nice clean product.”

She offers this advice for working with HDU.

“Make sure the material is primed and prepped so you get a clean and smooth finish.”

kendal signs

In January of 1996 Kendal opened a small sign shop in Rockledge, FL and today has become a leader in the industry.  Kendal Signs is now Brevard’s largest sign shop with an account portfolio that spans across the country. In addition to fabrication and installation, they service and maintain all types of signs, including electronic message centers. Tackling a job from start to finish gives them an edge over the competition.  Kendal Signs is pleased to be a full service, state certified contractor, and a MET Labs Approved and Inspected Sign Manufacturer.  You can call them at 321-636-5116 or visit their website.

Kendal Signs has recently purchased Daniel’s Wholesale Sign Superstore to help meet the signage demand industry-wide.  Sign companies now have the ability to order signs online through their website.

Coastal Enterprises manufactures Precision Board HDU, a versatile, cost-effective and eco-friendly urethane sign material that is particularly effective for making professional-looking indoor and outdoor dimensional signs.  It is a closed-cell rigid substrate that does not rot, warp or crack.  You can request free samplesget a quote or sign up for periodic newsletters packed with helpful information.


Never Say Never: Service and Quality Win Back Signetics


Founded in 1971, Signetics, located near Dayton, OH, is a full-service sign manufacturer serving the United States and the World. Originally targeting the golf industry in the form of interior and exterior signage, Signetics grew quickly based on reputation of quality and craftsmanship. Today, over 5,000 golf courses and businesses worldwide have signage crafted from their facility.

It’s the attention to detail that led Signetics’ President, Jeff Mize, to again use Precision Board Plus for their routed and sand carved high-density urethane signage. “After using Precision Board long ago and not sold on the quality, I vowed never to use it again. I never would use the word ‘never’ again,” says Jeff.


Getting a call from Coastal Enterprises in 2008, he reluctantly tried a sample of the new Precision Board Plus. Jeff adds, “I immediately knew they’d made a product I had to start using again. Sandblasting is the lifeblood of our facility and our craftsmen take great pride in producing the highest quality blast possible and Precision Board Plus helps us achieve that. Plus, I missed the customer service only Coastal Enterprises gives us because I know when I have a question – I get an answer.”

You can contact Signetics for your high-quality sandblasted and routed signage needs at (800)776-4152 or at










The Elegant Possibilites of HDU

Scott Brady, owner of SharpSigns in Forsyth, MO sent us a great picture of a sign he crafted out of Precision Board Plus for a bakery. They started by sandblasting PBLT-18 and adding smalt to the background. The letters were routed out of Precision Board Plus and gold leafed. To finish, the bagels and bread were hand-carved out of PBLT-18 and airbrushed. The design was collaboration between SharpSigns and Foppe Design.

SharpSigns website: