Comp Cams Shows How a Camshaft is Made
As consumers – car guys (and gals) who like to make things go fast, work better, or look good – our primary interest in any component for our vehicle lies in its actual benefits. Namely, how is it going to make your car run quicker, stronger, or whatnot. But as gearheads who live to get a little dirt under our fingernails and learn how things work, there also lies an inherent interest in the technical side of just how those components that we rely on are made. Especially a very precise item such as a camshaft.
COMP Cams, one of the leading camshaft manufacturers in the automotive aftermarket, recently took us for a tour of their production facility. There, we were given an in-depth look at every step of the process that goes into the finished product that resides in your high performance engine; from the drawing board to the design phase and the creation of the physical camshaft, and even the process of shipping it to your doorstep. And we’re here to bring it to you!
Who Are COMP Cams?
For over 32 years, COMP Cams has been a leading provider of aftermarket camshafts and valve train components for the high performance automotive industry. COMP and its COMP Performance Group (CPG) brands are driven by technology, employing the largest and most highly trained engineers in the industry, using the most sophisticated manufacturing and test equipment in the world. Comp manufactures valve train products for a myriad of applications; from motorcycles, to automotive, stationary power plants, diesel, medical; essentially anything that’s a stick with metal lobes on it.
We spoke with a group of talented engineers at COMP to gain an insider view at what goes into the making of a camshaft. Among them were VP of Engineering & Business Development Brian Reese, Mechanical Engineering Group Leader Corey Runia, R&D Technician Daniel Freeman, and Valve Train Engineering Associate Brad Brown.
One of the many OKUMA CNC mill/lathe machines used to carve and grind camshafts.
COMP encompasses four production facilities in Tennessee, Mississippi, Illinois, and Michigan. Within these are both full production facilities for large runs of products, as well as “short-run” facilities for the more custom and time-sensitive orders for race teams and such with a volume of less than 20. The short-run’s utilize ten Akuma CNC machines, three Landis CNC’s, and an estimated 25 manual machines for production of the camshafts. Likewise, the production facilities house fifteen CNC’s. Comp Camps employs upwards of 250 employees, and in all, it only takes roughly ten employees to handle the creation of a from-scratch camshaft design and five for an off-the-shelf piece to see it through from the design phase to the finished product.
Step One to a Camshaft: Design
The engineers at COMP Cams utilize many renowned software packages for various elements of the design process, as well as the company owns proprietary software.
For the creation of a new camshaft design, the process begins with a measurement and the collection of data involving the stock component, followed by strategic planning and engineering strategies in regards to the type of materials to produce the cam from, the design of the core, and the lobes. COMP employs the use of numerous different computer software packages for the design of their camshafts. These include AutoCAD, Autodesk Inventor, Solidworks, Pro/ENGINEER, and some proprietary in-house software among several other software packages for design, modeling, and analysis. One package of interest that the engineering team utilizes is Recurdyne.
“Recurdyne is a pretty neat deal,” explained Mechanical Engineering Group Leader Corey Runia. “We can actually take a CAD model of a part and we can put it in a simulation and actually test and run it live for dynamic analysis, but it takes a big computer and a lot of time.”
Despite the engineering precision that goes into the design of a camshaft from a design standpoint, the skilled team at COMP have got it down a science (literally).
“If it’s an iteration of a Pro Stock cam, it could be drawn in a day, no problem,” added Brian Reese. “If its, say, a new engine application, while something for a newer engine application ca be drawn anywhere from less than a full day to two days depending upon the complexity of the cam core and design.”
Step Two to a Camshaft: Production
Key to a quality camshaft is precision.
Once the computer design is complete, it is then passed along to the manufacturing department, who job is to formulate the game plan for production of the camshaft. This includes the material stock used for its creation.
“We make cams out of practically anything, [any] steel or iron that’s out there,” continued Reese. “There are more or less two categories. There are castings and there’s billet or steel. A vast majority of our cams are made out of 5160, but we have a very good number of cams that are made out of 8620, tool steel, M4 9310, and then the cast flavors.”
COMP maintains an inventory in the tens of millions worth of camshafts.
All of those different materials also add up to a mind-boggling figure of on-hand inventory at COMP. Reese explained, “We have about eight figures worth of raw material inventory in cams. That’s in the tens of millions. Strategically, this company has invested in inventory so that when people order, we can deliver. Without a doubt, we have more inventory than any other camshaft company in the aftermarket. Period. It’s not even close.”
The production phase begins with the print of the camshaft design being plugged into a proprietary program that machines out the tool paths needed to create the camshaft core.
Camshafts are initially carved from a steel bar into an oversized, rough shape that are later ground and polished.
A camshaft begins life as a simple round bar of the selected material. Like any modern facility, everything is computer controlled through the use of seven-axis mills and lathes all combined into one unit and can operate and carve two different parts at the same time. Essentially, it’s an all-in-one unit that can both carve and later grind the cores. The cores are initially carved into what is known as an UGL – or “unground lobe” – camshaft, which in layman’s terms is a basic camshaft core with oversized lobes that haven’t yet been ground into a specific and finished profile.
COMP carves their cores with enough extra material on the lobes that four-to-five different finished designs could be made from it. After the core itself is created, it is then heat-treated and straightened and all of the oversized places are ground down, beginning with the journal areas and face cuts. It is then placed back into the CNC grinder where the lobes are ground into the desired profile as programmed into the machine.
A grinder forms the camshaft core into a finished product with the desired profile.
“When we’ve got a design and a curve that we’ve come up with that we want to use on a certain cam, we actually utilize another of our in-house proprietary systems. When we go to the grinder with it, we actually have a couple different files output that we use, and we basically take the file and create another file that feeds into the grinder and feeds the actual motion of the grinder,” noted R&D Technician Daniel Freeman. “And just to tell you how sensitive that is – we can make changes out to the fifth or sixth decimal place feeding into the grinder and you can see the difference.”
Once ground, the cams go through an extensive quality control process like any manufacturing facility. COMP utilizes CMM’s (Coordinate Measure Machine), hardness testers, and surface gauges that are all electronic and highly accurate measurement tools. “The testing tools are sensitive enough that the temperature of the camshaft will change the measurement. And we measure the cam vertical rather than on its side, because the machines can actually measure the bend in the cam from the gravity,” Reese explained.
The valleys and lobes of the camshaft are polished by hand.
In just a scant 30 minutes, a steel bar can be formed into a complete, roughed-out camshaft. In the production facilities, the larger volume camshafts such as those found in catalogs can be completed within a week. And the volume numbers are quite staggering: COMP can produce, on the low end, 30,000 camshafts in one month at their short-run facility. In all, a camshaft goes through about 20 hands from the design phase the shipping.
Step Three to a Camshaft: Location, Location, Location
Camshafts are separated in bins in the shipping department prior to packaging.
Once complete, the cams are moved to the shipping department where there is a flow that all of the cams go through using COMP’s in-house tracking methods to be packaged along with paperwork and any included items. Cams slated for inventory will then go on the shelf, while those having been ordered will be shipped out. And that’s where another of COMP Cams’ key attributes comes into play.
“We can have FedEx pick up a camshaft and have it out on a plane within 45 minutes to the customer,“ noted Freeman.
So, there you have it. It’s a high-tech, fast paced process that focuses on time, quality, and efficiency. And if while piecing your high performance engine together in your shop, you’ve ever thought to yourself, “I wonder how they made that camshaft?” Now you know.