CR Onsrud Routed a Porsche 917k from a Precision Board Bonded Block

CR Onsrud wanted to show off their 5-axis Qube CNC machine at trade shows, so they got in touch with Coastal Enterprises to throw some ideas around.  Onsrud regularly uses Precision Board as demo material on their routers, but they wanted to really highlight the capabilities of the Qube for high-speed machining and trimming of advanced materials used for aerospace, automotive, marine, defense and pattern shops.  They decided they would fabricate a prototype of the Porsche 917k out of a custom-bonded Precision Board block live at IMTS 2018.  This is how they did it.

porsche 917k

While CR Onsrud sent a detailed drawing to Coastal Enterprises that laid out what the dimensions of the custom-bonded block would need to be, customers can submit anything from a rough sketch with dimensions all the way up to a detailed drawing.  We’ll design a custom bonded step-tool from that sketch or drawing, saving you material costs and routing time.

In order for Onsrud to machine the Porsche 917k shape out of the Precision Board, it would need to be 74″ x 34″ x 18″ and fabricated from PBLT-15 Precision Board Tooling Board.  Coastal would create three bonded blocks; one for testing at Onsrud’s facility in North Carolina, one for the International Woodworking Fair in Atlanta and one for the International Manufacturing Technology Show in Chicago.

According to Jeff Onsrud, Director of Sales and Business Development at CR Onsrud, “we typically will do a setup where we prove out the program and then do a final test cut at our facility.”  He added, “this ensures that there are no machining defects due to bond lines, which is important to achieving a usable mold straight off the machine.”

Onsrud did the Porsche project in collaboration with Autodesk, using their Powermill software.

The PBLT-15 Precision Board pieces were bonded together using EP-76, a two-part epoxy manufactured by Coastal Enterprises.

“We add PB Granules to the EP-76 epoxy to match the density of the material when bonding pieces together” said Chuck Miller, President of Coastal Enterprises. “This allows for smooth routing straight through the material without having to take bond-lines into account.  This also helps create an almost imperceptible bond-line in the finished piece and reduces issues associated with bond-line shrinkage and print,” he added.

When bonding custom step tools in-house, Coastal Enterprises has three adhesive options to choose from depending on the application and project requirements.  In most tooling applications we use our EP-76 Epoxy adhesive, but we also offer PB Bond 240 and PB Fastset.

The three bonded blocks were shipped to CR Onsrud who took them on the road to the IWF show last August and the IMTS show last September.  They sent us the video above from the live demonstration at IMTS of machining a Porsche 917k from a Precision Board bonded block.

Jeff added, “the Precision Board block was bonded together so tightly and the densities matched so perfectly that we didn’t even notice the bond lines when machining the material.”

CR Onsrud used their Qube CNC to rout the Precision Board with the following speeds and feeds settings:

  • Total cycle time was around 16 hours
  • Roughing feed rates were 500 inches per minute (IPM)
  • Finishing feed rates were 400 inches per minute (IPM)

And here’s another look at that Porsche 917k prototype being routed by CR Onsrud.

Of course, the fine folks at CR Onsrud had a little fun with this project, posting updates to their Instagram account throughout the process.  Our favorite is the “pretending to drive the car” photo.

The QUBE from C.R. Onsrud was developed for companies seeking 5-axis high-speed trimming and machining of advanced materials used in the aerospace, automotive, defense, marine, and pattern shop industries. This enclosed solution gives users a large work volume for machining molds, prototypes, and complex composite or thermoformed plastic parts while containing debris and isolating the operator from the machining zone and airborne particles. The machine design allows for various methods of work holding such as mechanical hold down and vacuum. Accommodation for oversized parts is achieved via removable side panels.

C.R. Onsrud, Inc. is located in Troutman, NC and specializes in 3-Axis and 5-Axis CNC Machining Centers, CNC Routers, CNC Mills, and Inverted Routers, primarily for the Composite Machining, Aerospace Industries, Plastics Routing, Hard Wood Routing, Panel Processing, Solidwood Routing, Aluminum Milling, Steel Milling, FRP machining, Composite Mold Making, Alloy Milling, Superalloy Machining, Carbon Fiber Machining, Carbon Graphite Machining, Door, Stair, Window, and Custom Millwork.

With its roots in Aerospace, Precision Board High-Density Urethane Tooling Board is specifically engineered to meet the demands of a broad range of tooling and tool making applications. Both PBLT Tooling Board (<200º F) and PBHT Tooling Board (<300º F), possess excellent machining characteristics and dimensional stability for tool making. Precision Board HDU Tooling Board is ideal for soft tooling and rapid prototyping because it can be more rapidly machined and it is more economical than alloy or epoxy-based alternatives.

Ask about our custom-bonded blocks, fast turnaround time, and sign up for our weekly e-blasts, including the monthly Tooling Tidbit (bite-size bits of info on using Precision Board).

MultiCam CNC Speeds and Feeds for Precision Board HDU

One of the more frequent inquiries we receive at Coastal Enterprises involves questions about CNC machining of Precision Board HDU. Typical questions include, “what type of cutter works best,” “where do I start with my speed and feed settings,” and “what should my chip load be?” We asked our friends at MultiCam USA to rout shapes with a CNC Router into PBLT-15, PBLT-30, and PBLT-40 densities of Precision Board and let us in on what speeds and feeds settings they used to achieve maximum results.


CNC is an acronym for, “Computer Numerical Control.” Essentially, CNC machinery is a computer operated mechanism which precisely cuts or engraves complex shapes in metal, plastic, stone, wood, and a range of various medium types. In order to accurately cut or engrave a design, a programmer must map a numerical code through CAD (Computer-aided Design) and/or CAM (Computer-aided Manufacturing) software which is interpreted by the computer and used as a blueprint or template.

MultiCam used their APEX3R CNC Router to cut different shapes and patterns out of our Precision Board HDU. Settings varied depending on what density they were cutting into. You can see those specific settings below and in the videos on our YouTube Channel. MultiCam used their own router bits to cut the HDU material.  They used a 3/16” Ball Nose (Part # 95-00047-52-260B) and a 1/2” End mill (Part # 95-00047-63-790).

In addition to the MultiCam router bits, a wide variety of HSS cutters commonly used for wood and plastics work very well for machining Precision Board HDU, and a wide range of settings will produce great results.

If you are not getting the desired results, try adjusting your settings. Different densities of Precision Board will require different settings, much like different grades of wood will have different settings.

Chip Load

You can optimize your chip load by setting the feed rate and cutter speed to yield the largest chip that produces the desired surface finish. While Precision Board HDU does not conduct heat and is non-abrasive, this will ensure that heat is carried away from the cutter, prolonging tool life. Here’s a useful formula from LMT Onsrud, manufacturer of router bits and cutting tools:

Chip Load = Feed rate/ RPM x # of flutes

 To increase chip load: 

  • Increase feed rate
  • Decrease RPM
  • Use a cutter with fewer flutes

To decrease chip load: 

  • Decrease feed rate
  • Increase RPM
  • Use a cutter with more flutes

With a little experimentation you’ll become an expert at machining Precision Board. Proper cutter selection and machine setup will produce a smooth cut, leaving chips that fall to the ground and do not become airborne. And because we’ve added an anti-static agent to Precision Board, chips will not cling to your work or your equipment.

Settings for Zeus (PBLT-15)

o FeedRate: 500
o RPM: 18,000
o Chipload: .0277



Settings for Long Horn (PBLT-30)

o FeedRate: 350
o RPM: 16,000
o Chipload: 0.19


Settings for Dragon (PBLT-40)

o FeedRate: 500
o RPM: 8,000
o Chipload: .0625



MultiCam is a global supplier of innovative CNC cutting solutions for industries ranging from sign making to digital finishing, sheet-metal to plate-steel processing, hardwoods to cabinet making, thermoform trimming to plastics fabrication, as well as a wide variety of aerospace and automotive applications.

Precision Board HDU can be cut with a router, waterjet or laser and can also be hand-carved. It is also eco-friendly with, “green” urethane components. It has a certified “Carbon Balance” of 3 to 1 and a “Rapidly Renewable resource Content” of 23.9%.  Learn more green facts here.

Need help with a quote? Click here or call us at 800-845-0745. We’d love to hear from you!

The Award-Winning Lunsford Think-A-Ma-Jig Sign

2018 marks Lunsford Sign Works 27th year in business.  To celebrate they decided to do a complete rebranding, including a new sign for their business. They set out to create a landmark sign that would really convey their passion for the craft and at the same time be a larger than life, traffic-stopping work of art.  To do that took four years of planning, countless man hours and a sign that would be put together with Precision Board HDU, aluminum, steel and glass.  Owner Joel Lunsford walks us through what it took to bring the Think-A-Ma-Jig to life.


“After 25 plus years, we wanted to shift our focus to what we really enjoy making: three-dimensional architectural signage, found object sculpture, custom lighting, dimensional illustration and decorative iron work,” says Lunsford. “We finally came up with the concept entitled ‘Think-A-Ma-Jig’. A magical device inspired by three of my heroes: Rube Goldberg, Dr. Seuss, (after all, some clients think that we can just pull out their creative designs from our cat’s tall striped hat) and world renowned dimensional illustrator, the late Eugene Hoffman,” he added.

It took Joel and his team about two years to get the design mostly finalized and ready for fabrication. Production took place over the course of another two years during their slow periods and was finalized last fall. It took more than 1,000 man hours to create the sign as they obsessed over every shop drawing detail. It stands 22 feet tall and weighs about three tons (not including the four tons of concrete at its base).

“We used every tool in the box to fabricate it including our CNC router, plasma and water-jet cutters, welders of different types and all of our heavy-lift equipment,” Joel adds.

Joel says, “the Think-A-Ma-Jig sign was fabricated from Coastal Enterprises Precision Board in multiple layers, aluminum plate, blown glass and steel. We used Matthews metallic paint finishes for all of the lettering and in direct sunlight the lettering acts like a golden beacon which is seen for miles!” He added, “Modern Masters Metal Effects rust coating was used on many of the Precision Board parts to make them indistinguishable from real steel and cut down on some of the weight. Because of the sign’s enormous girth, it was built in sections and assembled outside.”

Lunsford used PBLT-18 Precision Board HDU in two layers of the same density.  They used a Multicam CNC to machine and create the carved prismatic lettering and some of the machine-looking components.  The layers were all glued together using PB Fast Set.

Joel adds, “we like to use Precision Board because it’s easy to machine and durable.  Most importantly we like Coastal Enterprises as a company.  They have done a lot to promote our industry and care about their customers.”

Lunsford’s Think-A-Ma-Jig sign won an award in 2017 in the USSC Sign Contest for “Freestanding Sign, External Illumination or Non-illuminated”.


Lunsford Sign Works is an award-winning design and custom sign fabrication company located in the central Rocky Mountains. Their primary service area extends throughout the resort regions of Colorado, but their products can be seen both nationally and internationally.

While they are a full service commercial sign company, they specialize in hand-crafted, three-dimensional, architectural signage. Lunsford combines the latest in computer technology with old-world craftsmanship to create both electric and non-electric signs. You can visit their website or give them a call at 970-725-3925. They are located in Hot Sulphur Springs, CO.

Coastal Enterprises offers free samples of Precision Board HDU in any density.  Sign up for our newsletter so that you don’t miss any of our helpful blogs!

Routing Precision Board HDU with a Techno CNC Systems Machine

Techno CNC Systems has worked with Coastal Enterprises for a long time, so we thought it would be fun to have them fabricate a sign out of Precision Board HDU.  Bob Valentine put together a CAM design using both the Techno CNC Systems and Coastal Enterprises logos.  He then routed a 2″ thick piece of PBLT-30 into a work of art.  You can see the final product below and also get speeds and feeds information for cutting Precision Board using a Venture Plus CNC machine from Techno CNC Systems.


Speeds and Feeds for Engraving (1.25″ v-bit with 0.5″ shank):

Speed: 18,000 RPM
Feed: 1,000 IPM
Chip Load: 0.05″
RDoC: 0.6125″
ADoC: 0.5″

Speeds and Feeds for Endmill (0.5″ flat endmill upcut):

Speed: 18,000 RPM
Feed: 1,000 IPM
Chip Load: 0.027″
RDoC: 0.25″
ADoC: 0.76

Since 1986, Techno has been solving the toughest manufacturing challenges helping sign makers, woodworkers and general fabricators with their production needs. Their CNC equipment is designed to route, carve, drill, and engrave in wood, plastic, foam, aluminum and other materials for a wide range of applications.  You can contact them at (631) 648-7481 or visit their website.

Not sure which density of Precision Board you need for your project?  Review our Material Selection Guide to choose which density and whether you need PBLT (low-temp) or PBHT (high-temp) Precision Board.  You can also request free samples.


Lost and Foundry: Restoring a WWII Era 16″ Lathe

Tom Utley is doing a detailed restoration of a WWII-era South Bend 16″ x 60″ metal lathe, which is about 9 feet long and weighs 2,700 pounds fully loaded. It was originally delivered to the US Army in June of 1943 with the Crossed Cannons logo of the Army Ordnance Corp stamped into the bed. Tom bought the lathe a few years ago and has been working on a complete factory quality restoration ever since. These parts are his attempt at packaging modern electrical controls inside original Art Deco design cues found elsewhere on the machine. He used Precision Board HDU to make detailed foundry patterns for cast iron parts.

metal lathe

Tom used PBLT-48 for his casting patterns, but you can also use higher densities like PBLT-70 and PBLT-75.  Precision Board is easy to work with and cost effective.  It has excellent dimensional stability to create accurate casting parts.  If you’re not sure what density of Precision Board to use for your project, take a look at our Material Selection Guide for reference.

In addition to having the machine reground and hand-scraped (a technique to restore precision sliding surfaces to very high tolerances), Utley added a few bells and whistles to make it easier and safer to use for himself and his young son.

“I added modern electronics, including a variable frequency motor drive and safety switches that weren’t commonplace on old machines like this.  I also worked out a means of adding a custom analog (dial face) tachometer that indicates spindle RPM.  It’s actually an aftermarket diesel automotive tach from Speedhut, but with a little custom artwork on the dial it could pass for an original factory option if you don’t look too closely.  A tachometer would have been found on high end machine tools of the day, but was never offered by South Bend back then.”

All these new electrical items needed an enclosure to keep them dry and out of the way of flying hot metal chips.  Tom could have picked up aftermarket electrical enclosures and bolted them on, but after all the work to restore the machine it didn’t feel right to him to get so far away from the Art Deco styling found on War-era machines like this.  So, after lots of hand sketching and cardboard templates, he came up with a design that felt like something South Bend might have offered in the 40s if tachs and safety switches and variable speed knobs had been factory options.

“I decided early on that I wanted these new parts to be made from cast iron just like the rest of the machine'” says Utley.  “Castings require patterns, so I set about learning everything I could about the process, mainly via the Web and YouTube. I received a lot of help from the Maker and YouTube machinist community throughout this project.”

foundry castings / foundry patterns

A few months ago, Tom was fortunate to meet John Saunders who runs the NYC CNC YouTube channel.  John was enthusiastic about the project and offered to cut a casting pattern for him once he had a CAD model.

“I had to teach myself how to use Autodesk Fusion360 for modeling the parts, but after a few weeks I had a usable 3D CAD model of what had been bouncing around in my head,” said Utley.

To compensate for any dimensional and structural changes which will happen during the casting or patterning process, allowances for shrinkage are usually made in the pattern. Talking to Emmanuel King, owner of Cattail Foundry in Pennsylvania, Tom was advised to scale the casting pattern up by 1/8″ per foot of finished part dimension to offset shrinkage in the cooling iron.

“This is a snap to do in Fusion360, all I had to do was tell the software to scale my model by 1% and it was ready for the CNC.  The CAD model was then shared with John directly from my PC and he set about carving the two patterns.”

Being used to cutting metal, John had to go through a bit of a learning curve with feeds and speeds and workholding, but ultimately found Precision Board to be easily machinable.

After a little bit of hand sanding by Tom, the casting patterns went off to the foundry.

Earlier this month, Utley received the castings back and they turned out great.  The foundry owner said the material is great for casting short run parts like this and complimented him for having draft angles in all the right places and for making it so smooth for his foundry team.

Tom is doing final machining on the castings now.  Once that’s done and the castings are painted, he will add custom acid-etched brass legend plates for each switch and get the wiring all buttoned up.  The two year project will finally be to a point Utley can call it done and move on to his next machine tool, which he hopes will be a milling machine.

“Thanks so much for sharing the story of this old machine–she’s 74 years old now with a lot of history, but she’s just about ready to debut as a brand new beautiful girl with at least another 74 years of making chips ahead.  Publicity like this is great because it gives people the confidence to take on bigger restoration projects like this and save good machines from the scrap yard,” he adds.

You can read a more detailed journal of Tom’s restoration efforts, including photos of the lathe in its original condition here.  He can be found on Instagram where he shares photos of this and other projects he’s working on.

If you want to try out Precision Board for yourself, you can request free samples, get a quote, or find a distributor near you with our directory.

UPDATE: You can read an article in the December print issue of Production Machining about Tom Utley and his restoration project or read the online version HERE.