A North Carolina shop uses composites to reduce weight
What is 30 to 40% lighter than aluminum and twice as strong? Answer: composite structures made with epoxy impregnated carbon fiber. The material provides the weight advantage and the component’s geometry determines its strength characteristics.
Since weight reduction is so critical to improved racing car performance, Fibreworks Composites LLC (Mooresville, NC), has barely been able to keep pace with orders for custom racing seats and other race car parts since the composites manufacturer opened in 2009. A deluge of short-run production and prototype assignments from race teams and OEMs has driven sales growth at an annual pace of 20% or better.
Fibreworks uses a wide variety of composite manufacturing techniques to achieve customer requirements. Almost all of these involve the use of geometrically complex sculptured patterns and/or molds made from high-density polyurethane foam tooling board. The company initially ordered these from external suppliers. They were expensive purchases, since the 4 x 24 x 60″ (102 x 610 x 1524 mm) tooling boards alone cost about $1000 each. That’s before any manufacturing content is added. Worse still, lead times for the boards were a week or more. This was a barrier to growth since race teams frequently need their assignments turned around within days.
Fibreworks co-owner Joe Hofmann said, “In 2012, we decided to take destiny in our own hands and purchase a five-axis router and CAM software,” and now use Mastercam CAD/CAM software from CNC Software Inc. (Tolland, CT).
A Different Level
“Today, instead of just making a composite part, we can design, develop, and manufacture. That includes machining all the tooling, molds, and patterns in-house and the manufacturing of parts. We are essentially a one-stop shop,” Hofmann said.
“We take on a lot of projects where we can provide engineering support from the structural analysis simulation side to design and put the whole composite package together. This is what large OEM customers are looking for. This is the type of resource that was previously available only in Europe. It did not exist here before at the level we do it now.”
Fibreworks does all of its design work in CATIA, putting it on the same page with designers from major OEM race teams. CATIA data can be flowed seamlessly into the structural analysis package, which is an essential tool for assessing how the geometry of lightweight components contribute to strength. Once the design has been optimized, the same CATIA data also translates directly into Mastercam, where it is used as the basis for creating patterns and molds.
Fast Track from Concept to Part
“When I first started here, the owner asked which CAM system we should get, and I suggested Mastercam because it goes from a concept on the screen to a part faster than any software I’ve ever used,” said lead programmer Alan Crawford. “To me, it is more of a machinist’s software. There are a lot of software programs that try to do things for you, what is called feature-based programming. Mastercam can do that, but in those cases, it makes a lot of assumptions about what the tool should be doing. I am more of a control person. I want to be in complete control of what the tool is going to do. I don’t want to sit there and try to trick the software into doing it with a feature-based program.”
Total control of the tool makes it possible to create the complex, free-flowing organic geometries that are so essential for imparting strength into lightweight composite structures.
For example, Fibreworks ships a high volume of race car seats every year, and creating these geometries for five-axis machining has made it possible to meet SFI and FIA standards with structures substantially lighter than aluminum. This capability also allows them to create safe seats that allow the driver to have a lower center of gravity as he sits in the vehicle.
Control is also important because everything the company does is time sensitive. If a part comes in from a racing manufacturer, it wants it in days, or a week at the most. Once Crawford has brought the design in from CATIA, he will jump right into programming. Soon, he will have the tooling board up on the machine and while the router is making the roughing cuts he will be completing the program so that no time is wasted.
As Fibreworks became more adept at using its CNC manufacturing capabilities, the company began expanding its uses. For example, a significant number of metal parts for such applications as threaded metal inserts are now being produced in-house with Fibreworks’ own CNC equipment. Trimming of composite parts that once consumed numerous man-hours has also been automated using Mastercam’s trimming toolpaths.
Traction for Growth
The types of parts racing teams are looking for continue to expand. Seats and helmets are now routine. The aero kit, composed of any body parts that are painted, is wide open for composite parts. Even NASCAR rules have changed, opening the door to such innovations as carbon-reinforced metal hoods. Under the hood, turbo plenums, ducts, pipes, and other air-moving devices are in greater demand as long as they can stand the temperatures and pressures.
“Because we offer a unique resource to companies that are seeing the benefits of high-performance composite parts, we are starting to get a lot of traction from aerospace and satellite companies, which are outside of our normal arena but offer us an additional path for growth,” Hofmann said.
A major focus for Fibreworks in 2017 is to capitalize on these opportunities by moving to a new 20,000 ft2 (1858 m2) plant and installing two more advanced five-axis routers. This will boost existing capacity by about 50%. As for lead times, Fibreworks is doing its best to keep pace with a very demanding customer base.
Edited by Yearbook Editor Bill Koenig from information supplied by Fibreworks