Whitehurst Enterprises, LLC.

Inexpensive, Accurate CNC Router Helps Start Production
Woodworking Business, Whitehurst Enterprises,LLC

An inexpensive but highly accurate and productive computerized numerical control (CNC) router has helped a CNC programmer start a successful new production woodworking business. Brian Whitehurst previously worked for a reseller of leading high-end CNC programming software, helping customers solve difficult programming challenges. Then Whitehurst saw a market opportunity and decided to go off on his own, producing complicated architectural ornamentation that was up untill now mostly made by skilled craftsmen working with power tools. Whitehurst has carved out a substantial market niche by producing decorative wood carvings much faster and at higher levels of accuracy on CNC machines. "CNC machining is taking the architectural ornamentation industry by storm by producing a better product at a lower price," Whitehurst said. "The key is the availability of low-cost CNC machines that can accurately duplicate a computer aided design (CAD) program in much less time than someone working by hand."

In his previous job, Whitehurst was a senior applications engineer representing Delcam, a leading international CAD/CAM software supplier to the mold, tool and die sector. His job was to work with manufacturing businesses that were having difficulty producing complicated parts, determine a software solution that would meet their needs and train their people in how to use it. When very difficult problems arose, Whitehurst would go in and write the CNC program himself. He enjoyed working for an industry leader but felt the urge to start a business of his own. He looked for an industry where he could apply his considerable programming skills. Even though the majority of his experience was in the metalworking industry, he was drawn to woodworking because so many companies in that business were still using power tools to produce the increasingly complex parts being demanded by the architectural market. Another attraction of this industry is that woodworking machinery is much less expensive than metalworking machinery because it doesn't have to be built to withstand the high forces often generated in cutting metal.

Better quality at lower prices
"I was confident that I could provide far better quality and lower prices by using a CNC router to compete with companies and individuals that were producing carvings by hand," Whitehurst said. Producing complicated pieces such as carved moldings and friezes is a very slow process by hand. The job of producing the first piece is typically assigned to a very experienced and highly paid craftsman who cuts it out with hand and power tools. Then less experienced workers typically duplicate the piece using a tracer. One problem with this approach is that even the most skilled woodworker has difficulty accurately producing three-dimensional contours. The result is a piece that requires extensive finishing by hand, to chisel and sand the piece the way a customer wants it.

"The beauty of a CNC router is that you can define every detail of the piece to absolute perfection in your CAD/CAM software and then do something else while the machine produces the part," Whitehurst said. "While the CNC machine isn't perfect, the accuracy of the better machines is far beyond what can be achieved by hand. And every piece that you make will be just as good as the first one, such that each piece coming off will need little hand finishing. While programming is a labor-intensive process akin to cutting out the first piece by hand, once it is completed other pieces can be produced without the attention of a person except for loading raw wood and unloading finished pieces on the router and occasionally checking to be sure the tool hasn't worn out or broken. The result is that architectural ornamentation can be produced at a much more competitive price on CNC routers."

The first critical decision facing Whitehurst as he began operations was which CNC machine to purchase. He was aware that a new class of machines that has appeared over the last several years is far less expensive than machines designed for metalworking yet offers similar accuracy on wood and plastics.

After studying these machines, he selected the Techno model 210 PC-driven CNC wood router from Techno Inc., New Hyde Park, New York. This router, which sells for about $30,000 complete, is designed for production routing and drilling on a wide variety of materials including wood, plastic, MDF, solid surfacing materials, and nonferrous metals. "I liked the Techno router from the start because it is flexible and easy to use. As I learned more, I discovered that it's also very adaptable to nearly any woodworking problem. For example, long pieces of molding can be stacked side by side while the spindle traverses each piece to cut the pattern. On the other hand, multisided pieces like a corbel, can be mounted on a rotary table that moves the appropriate face towards the spindle one after another. Best of all, the router only costs about the same as my car payment every month."

The Techno router is constructed on steel stress-relieved bases with hardened steel linear ways. Its shaft and bearing system produces very smooth, play-free motion and is an extremely rigid system that produces high-quality cuts. The router also uses anti-backlash ball screws. These screws have excellent power transmission due to the rolling ball contact between the nut and screws. This type of contact ensures low friction, low wear, and long life. The ball screws also make it possible to produce wooden parts to the machine resolution of 0.0005 inch. Instead of being ball screw driven, the less expensive routers use rack and pinion gearing, which has too much play to make accurate cuts in small areas. Also this type of gearing wears out quickly in the dusty environment of a carpentry shop. The other main difference we found between the Techno router and the others was that the Techno uses a servomotor to control cutting motion while other routers use stepper motors, which can give a stair-step cutting effect.

Producing anything that customers ask for
"With this setup, I have found that I can produce just about anything that customers ask for," Whitehurst said. "For example, one customer asked for a molding that looks like a grapevine with the grapes protruding in 3D. They gave me a picture of what they wanted which I scanned and then turned into a 3D model. To transform the 2D image into a true 3D relief with a hand-carved look works this way. The artwork is colored by the use of brushes and flood fill tools and each color is assigned to an individual 3D shape profile. The different types of profiles that can be generated include plane, round and angular. The parameters of these profiles are controlled by defining the basic shape, start height, limit height and wall angle, giving almost total control over a wide range of 3D effects. The program builds 3D reliefs by assigning a height to each pixel in the 2D image. I provided my own artistic interpretation and also designed the molding in such a way that it can be machined quickly. I cut a sample piece in MDF, give it to the customer, and listen to their feedback and then modify the program so that the finished pieces are exactly what they want. If the customer ever needs more molding, I can simply call up the program again and match the original order to a tee."

















"Another interesting piece that I made recently is called a corbel – a triangular decorative bracket that fits in the corner between a ceiling and wall," Whitehurst said. "The program takes a solid block of wood and whittles it down to an intricate 3D design on three sides. The complexity was so great that I didn't get it exactly right the first time but as nearly always, I cut sample parts in inexpensive wood and then measured the errors and used them as an offset to correct the program." Whitehurst said that his new business has also spawned several offshoots. While he is building his production machining business, he also acts as a consultant to other woodworking companies that want to establish a 3D machining capability and provides custom programming services. "The Techno router is intelligently designed so that I can plug my own devices into the various ports and provide commands in the program to turn on a dust collector and an air blast to clean the tool," he commented." I also have a digital video camera pointing at the machine so I can log in while I am visiting a customer's site to see how everything is going. In the future, I plan to add a tool breakage sensor that will send me a page or an email when a tool breaks in order to provide for fully unattended operation."