Supercharged for the Future
Machining dovetail O-rings of various sizes and iterations for racecar superchargers is easier, more accurate, and takes less time with the right software and specialty tooling.
Mill 3D, Multiaxis, Lathe, Dynamic Motion
The late Jerry Magnuson is a legend in the hot rod racing and aftermarket industry. He and his wife Maureen Magnuson started Magnuson Products, LLC in Ventura, California, after many years of designing and building supercharger kits for the aftermarket. The company also supports OEMs. Magnuson sold the company to Kim Pendergast in 2010.
According to Hubert Gromek, machine shop manager at Magnuson, every little part of the superchargers, down to the most miniscule component, is important. That is why, after many years of outsourcing various machining processes, experiencing longer lead times and, at times, substandard quality, they invested in CNC mills, lathes, and Mastercam to power the operation. Today, nine machinists help churn out approximately 3,000 to 4,000 parts per month. Eighty to ninety percent of all products are produced inhouse in two shifts per day.
The majority of parts manufactured at Magnuson are made of sand-cast aluminum – 328 and 356. They range in size from small brackets to full housings for big upper and lower manifolds that can be as large as 22” x 17”. These parts are often intricate in terms of port design, flanges that must be super flat, and O-ring grooves in various iterations. Engineering, with whom Gromek works closely, started designing dovetail O-rings, and he had a hard time finding a tool that could do the kinds of dovetails they needed. His tooling distributor suggested the Helical Tool dovetail cutters from Harvey Performance Company, a Mastercam partner.
“The dovetail O-ring is tricky. You have to rough out the slot with the smaller endmill. Some of these could be a nice short little O-ring or some can go around the entire sealing flange of a pretty decent size lid. The ones we mainly use are the 0.093” so it’s a 3/32nds endmill—pretty small—and when we have to go all around the sealing flange of a supercharger system, the run times would get pretty long when roughing these O-rings,” said Gromek. He is now able to rough out material and then go back in with a dovetail tool to achieve a good finish and evacuate chips effectively. “I was able to double the feed rates and, with Mastercam, I can program where the entry hole is and where the exit hole is, which is more efficient.”
Gromek uses standard contour toolpaths to program a circle helix bore toolpath for the entry hole; rather than plunging into the material and clogging up the tool, the helix bore “helixes” down to create the first starting hole. He then programs a standard contour toolpath to profile the circle toolpath.
Every type of supercharger has some sort of sealing flange. “Almost every single part we do has some sort of O-ring groove. There are O-ring grooves that go all the way around a cover that can be as large as 20” x 15”. By combining the right tools and toolpaths, Gromek has shaved considerable time off of his machining process.
“In machining, there is not one way that a part has to be done. There are a lot of CAM software programs where you have to do it their way. With Mastercam, you really do have a lot of options to choose from. Being able to do the different types of toolpaths, especially the Dynamic Toolpaths, has come in handy quite often.”-Hubert Gromek, Machine Shop Manager, Magnuson Products, Ventura, California
“The people at CAD/CAM CONSULTING SERVICES are always very helpful. They’ll walk you through step by step, the way that they would do something, and it gives me a very good baseline as to where to start.”– Hubert Gromek, Machine Shop Manager, Magnuson Products, Ventura, California
Machine intricate, complex parts with superior finishes in a variety of different materials for high-performance aftermarket and OEM superchargers.
- Different toolpath options from standard to highspeed are available for machining dovetail O-ring grooves of varying sizes throughout a supercharger.
- Verify feature allows programmers to see the entire machining operation before it runs, resulting in a simplified post code for the fork plate.
- Partnership with Harvey Performance allows Helical tool selection from all sizes and shapes with recommended feeds, speeds, and coordinated highspeed toolpaths for more accurate cuts.