Volume production of the last wooden boats ended about 1966, however, their ride, appearance and romance still appeal to many enthusiasts. When Travis Hickman began restoring wooden boats in 1986, he faced the difficult task of measuring an existing boat, creating 2D drawings, translating the drawings into marks on full-size boards and cutting out the individual boards on a bandsaw. The accuracy achieved with this method depended on the skill of the individual craftsperson.
Hickman has since implemented a new process in which the boat is measured with a laser transit. The measurements are used to generate a 3D model of the boat. The 3D model is used to create a program to produce the boards on a Techno computer numerical control (CNC) router. “This approach takes less time than the previous method to produce the first boat and replacement parts or additional boats can be made in a small fraction of the time required for the first,” Hickman said. “The accuracy of the new method is also much greater since the CNC router reproduces the parts defined in the 3D model with a high level of accuracy, regardless of the skill of the operator.”
The End of an Era? Not Yet!
Chris-Craft produced its first wooden boats in 1923 and began making them on assembly lines in the early 1930s. At their height in popularity, the company made tens of thousands of boats every year. Fiberglass boats were introduced soon after World War II and gained popularity because they were less expensive to build and required less maintenance. But the appeal of wooden boats has endured long after they stopped rolling off the assembly lines.
When Hickman began restoring wooden boats, he was one of the few people in the business. He rebuilds the engine, restores the upholstery and replaces the wooden frames. The first step in replacing the wood is to capture the lines from the boat using one of several possible measuring devices. Hickman uses a surveying tool called a laser transit. He sets up the laser in the back of the boat and shoots a straight line down the center of the craft to the bow. Then he uses a ruler to measure the distance from the laser line to the hull along the length of the boat.
Moving to CNC Machining
Hickman was interested in saving time and improving accuracy by moving to CNC machining. CNC has the advantage that the user generates a CAD model of the product and then uses the CAD model as the basis of a program that guides the machine tool to cut out all of the parts needed to build it. CNC machining is much more accurate because the program rather than the craftsman guides the machine and additional parts can be created from the program with little additional effort. When he first looked at CNC machines they were expensive and he did not feel that he could justify purchasing a machine because he would be using it only periodically.
“Then I discovered that Techno offers a great machine – the LC4896 CNC router – for a very reasonable price,” Hickman said. “With a 48 by 96 inch table the router is large enough to handle every piece that goes in a wooden boat. The machine and software was within our budget. Techno provides excellent support and has provided information that helps me to get the most out of the machine.”
Techno’s LC Series machine provides ball screws on all three axes, offering smooth motion, a high level of accuracy and repeatability and minimal maintenance. A closed loop servo control system provides constant position feedback, higher power, and smooth continuous motion that eliminates the possibility of losing position in the middle of a part. The machine comes fully assembled and includes Techno’s Windows-based CNC G-code interface with free lifetime software upgrades.
More Efficient Process
The CNC router enables a more efficient process for building wooden boats. The existing boat is measured using the same methods that were used in the past. But the lines that are produced by the measurement process are now used to create a 3D model of the boat. The model allows Hickman to pull measurements from the existing hull and compare these measurements to the model without totally disassembling the boat. Then Hickman pulls sections from the model at the frame stations to generate the profile of the wooden frame members. For each member, he generates a CNC program that automatically produces the part on the router. This eliminates the need to produce 2D drawings of the various structural members.
He then moves the CNC program to the router, loads one or several pieces of wood onto the router table and pushes the switch to start the router. The router then automatically produces the parts included in the program. This approach greatly reduces the need for skilled labor since the machine operates automatically, requiring only loading and unloading. Parts are produced to a much higher level of accuracy than in the past – 0.001 inch repeatability and 0.0002 inch resolution.
Rebuilding a Racing Boat
Hickman has used to these methods to rebuild and build from scratch other vintage boats. For example, he restored Bill and Judy Fisk's Vintage Hydroplane GP-317 with a 7 liter Lauterbach engine. The boat was built in 1971 and raced frequently ever since. The restoration started with a full inspection of the hull after the decks were removed. The inspection revealed many broken pieces and weak joints. The damage to the hull along with repairs made during her long racing carrier dictated rebuilding the boat from scratch. Hickman created the 3D model and let the customer view it and pick out the colors. After Hickman created the CNC programs, it took only 45 minutes to cut out the pieces for the frame on the CNC router compared to 70 hours that would have been required on a bandsaw.
“The Techno CNC router has substantially improved our business by helping us improve accuracy and save time,” Hickman concluded. “The router has paid for itself many times over by saving time in producing frame parts. In particular, the router opens up the potential for making multiple boats at a considerably lower cost than was required to make the first one. We can also make repair parts very quickly and easily. All in all, the router has helped us be more profitable and make our products more appealing to a broader audience.”
For more information on the machine described in this article, contact Techno Inc., 2101 Jericho Turnpike, New Hyde Park, NY 11040. Phone: 516-328-3970, Fax: 516-358-2576, E-mail: email@example.com, Web site: www.technocnc.com
Have something to say? Share your thoughts with us in the comments below.