Delcam’s PowerMILL gives Wegner Motorsports high-speed port machining

Using Delcam’s PowerMILL to program its Bostomatic 505 five-axis machining centre lets Wegner Motorsports turn around a set of performance cylinder heads more rapidly while improving surface finishes.  Whereas it used to take between 20 and 26 hours with multiple set-ups on a three-axis machine, a set of ports can now be machined in 45 minutes.

Carl Wegner started Wegner Motorsports in a machine shed in the backyard of his central Wisconsin farm in 1975, working for local hot rods, pick-up trucks and even an occasional farm tractor.  As his reputation grew, so did the list of customers.  The company now employs more then 30 people and takes up more than 7,500 square feet of the original back yard.  Wegner engines have competed in nearly every NASCAR division, including winning multiple championships in the BUSCH Grand National series, while Wegner short-track engines have won championships on asphalt and dirt throughout the United States.

A big part of Wegner’s success recently is CNC cylinder head porting.  The first step is hand grinding by an expert, a process that combines experience, craftsmanship, and persistence.  The difficult part is making each head the same.  With hand work, it is almost impossible to be perfectly consistent.

Once the ports have been created manually, the inside surfaces are scanned and the resulting NURBS file brought into PowerMILL.  Within the software, Wegner engineers specify tools, create toolpaths and check for clearances.

Within one to two days, an entire set of cylinder head ports can be recreated from an original, machined, tested, and installed into an engine.  The ability to turn out a complete set of cylinder head ports that duplicate a hand-ground original is making a major difference in Wegner’s business, according to Casey Wegner, Carl’s son and head of the CNC department.  "Previously, with a three-axis vertical machining centre, it would take us between 20 and 26 hours to machine the ports,” he said.  "Now, we can complete a head in about 45 minutes.  Plus, people in the industry are amazed at how smooth the walls of our ports are.”

Saving time programming is another major help.  PowerMILL lets Mr. Wegner try out the programs and simulate the tool paths before uploading to the machine, so he can know right away if a program will work efficiently.  Wegner does not have the luxury of time for test cuts and try-outs with the tools.
 
"Delcam has been a big help in listening to us and has been willing to change the product to suit our needs, which makes the CAM part of the job a lot easier,” concluded Mr. Wegner.  "Time saving is a big benefit to our entire operation, allowing us to do more in the shop overall.  It lets us spend more time designing in more horsepower.”

14 May 2007