Precision Multi-Axis Machining Company Combines Materials Expertise With Dedication to Craft

Machine operators at Evden Enterprises are taught to communicate respect for their customers by how they approach their work

March 22, 2023

By Mark Shortt

In the world of precision manufacturing, it isn’t rare for a machine shop today to have multi-axis machines that provide superior quality. But for Steve McGrath, vice president of manufacturing at Evden Enterprises, a custom CNC machining company in Ukiah, California, a better indicator of a manufacturer’s prowess is the people who are operating those machines.

McGrath told Design-2-Part in an interview that what separates the better machine shops from others is their people—specifically, the added value that they contribute through their knowledge of, and expertise in, multi-axis machining.

“The machine itself means nothing. It’s the people who are running it and programming it that make the difference, and make it successful,” McGrath said.

Evden Enterprises specializes in multi-axis production machining, employing an array of advanced manufacturing equipment to create parts from materials that are often difficult to machine. Working out of its 10,000-square-foot facility in Northern California, a region known for product innovation, Evden crafts custom parts for medical devices, laboratory testing devices, and electronics for oil and gas drilling applications, among others.

The company operates multi-axis CNC machines ranging from the basic 3-axis variety all the way up to today’s most coveted, state-of-the-art 9-axis machining centers. “The more axes you control on a part, the better quality parts you have overall,” McGrath said. “Because the machine can manipulate the part a lot more efficiently, a lot better than a human being can.”

Each level of multi-axis machining, from 3-axis on up, enables Evden to machine more sides of a part in a single setup, or single manufacturing run. It’s advantageous for quality and repeatability from lot to lot because it eliminates the human error associated with handling and locating the workpiece.

“You’re not taking it from a lathe operation over to a mill, and then locating it against something to mill the holes,” McGrath said. “If you have the machine tool itself do all the operations and all the sides of the part, that’s your most accurate way of producing the part. You have more control over the quality and the repeatability of the manufactured lots that you run for customers. So they’re confident that if they buy 100 today, and they buy 100 in 6-to-8 months, both lots will be identical and consistently in spec.”

 

For 5-axis machining, Evden operates two Matsuura MAM 72-3VS Machining Centers that are capable of handling workpieces 300mm in diameter and 250mm in height. For results that can’t be achieved on other CNC machines, the company relies on its 9-axis multi-tasking centers.

Evden has a pair of Willemin-Macodel 508MT, 9-axis Multi-Tasking Mill/Turn Centers with 35-mm bar capacity. It also has two Index G-200 mill-turn centers on hand. They offer dual turret/dual spindle with B-axis capabilities and 51mm bar capacity, according to Evden’s website.

McGrath said that when 5-axis machine tools were introduced in the 1990s, Evden was among the first to purchase one. The company had more of an advantage then because few shops were doing 5-axis machining. Most were still manually fixturing, locating, and loading, versus having the machine tool do the work.

Fast forward to 2023. Machine tools are more sophisticated, as is CAD/CAM software, and many more companies are deploying the latest technologies. What gives machine shops an edge over their competitors today is their personnel—the people who are running the machines and programming them, and their dedication to their craft.

“I view machining as an art form or a craft,” McGrath said. “In order to be exceptional at it, you have to really be enthusiastic about it—about learning it, about remembering what type of machining techniques work in certain situations, and what don’t.

“Again, it comes down to the experience and the knowledge of the people who are operating the machines. It’s not necessarily, ‘Okay, I’ve got a 5-axis machine here. Now I’m as good as any other 5-axis machine shop.’ It doesn’t work that way. It takes a lot of time and a lot of experience to be able to use that machine tool efficiently,” to the point where they can be considered world class operators, he said.

Getting to that level of proficiency is not easy, and it can be difficult to find capable operators. While the ability to control more axes on a part machining operation enables better quality parts overall, it also introduces another level of difficulty for the machine operator. McGrath said that as more axes are added to a machining operation, it puts more responsibility on the operator, who needs more knowledge to do the job.

“The operator of a 2-axis lathe doesn’t have to think too hard about producing the part. Versus now, if you’ve got multiple surfaces and angles on the part, one side affects the machining of another side. You have to be able to visualize that in your head and plan your tooling accordingly. Not a lot of people have that capability.”

McGrath makes his team well aware of the connection between their passion for their work and customer satisfaction, and that it involves more than technical ability. It also means respecting the parts that they’re making. Although machine operators typically don’t have one-on-one contact with customers, they communicate respect for their customers by how they approach every facet of their job.

“I’ll tell a guy, ‘I want you to take care of the parts on the machine and in the work carts,” he said. That means, among other things, avoiding clamping maneuvers that can put “dings, divots, and scratches,” on the parts. It also means not taking a nicely turned part, fresh off a milling machine, and just throwing it into a work cart, no matter how simple the part appears.

That attention to details, such as surface finishes, starts at the top. But McGrath credits his workers, the people on the floor, who take care of business and appreciate the quality and appearance of parts that will be going out the door.

“I tell them, ‘That’s you communicating to our customers that we care about your parts, and we are here to make the best product available—not just do a hack-and-stack job where the parts are all beat up.”

McGrath’s efforts appear to be paying off. “I get compliments from my customers all the time, saying that the parts they get from us are the prettiest parts they see from all the machine shop accounts that they have,” he said.

Assisting Customers with Materials Engineering

Evden’s team is experienced in working with a broad scope of materials, such as stainless steel alloys, aluminum, high-temperature alloys, titanium, Hastelloy, brass, bronze, and engineered plastics. Before starting a manufacturing project, the team advises customers’ engineers of ways they can control the costs of their part design. McGrath was careful to note that Evden does not get involved in a customer’s end design, but can assist “on a materials engineering scale versus a design engineering scale.”

“Materials engineering is essentially our specialty. We might suggest to a customer that if they want a certain feature, they need to do it a different way,” McGrath said. “We’ll provide some information on machining that material so they can decide whether they want to go that route, or whether they want to spend thousands of dollars on a specialty tool.”

Custom Machining Is Key to Innovative Products

Evden’s knowledge of machining enables it to make a variety of custom parts, including those that are desired by companies looking to create unique and innovative products. In one example recently, Evden helped a medical supplier that had designed an extremely intricate, high-tolerance part. The medical supplier had already tried different ways of manufacturing the parts, thinking it wasn’t possible to machine them.

One of the processes the customer tried was additive manufacturing, which failed to deliver the tolerances and quality they required. They tried making the product out of several different parts and brazing them together, as well as EDM work, but the cost was prohibitive. Then they found out about Evden’s 9-axis Willemin-Macodel multi-tasking mill/turn centers.

“They just called me out of the blue and sent me a print and said, ‘Do you think you could machine this?’ I said, ‘I think I can. I can give it a shot.’ And they were completely blown away that I was able to machine them. They’ve developed into a very good customer over the last year.”

Ensuring High Quality Parts

Evden ensures high quality production through its commitment to strict inspection procedures, including in-process inspection and compliance with a MIL standard inspection system. The company also maintains up-to-date calibration of its Zeiss CMM (coordinate measuring machine), which it uses as a master gage for all the measuring equipment in its shop, McGrath said.

Evden doesn’t do 5-axis machining on jobs where the blueprint doesn’t require such high levels of accuracy. In such cases, it might do two lathe operations, then move the part to a milling machine and perform one or two quick milling operations. Inspection is performed at every point along the way, McGrath said.

“On the first lathe operation, you have written instructions on what to check, how often, what tools to use for checking, whether it be micrometers, gage pins, or what have you,” he said. “When it goes to the second lathe op, everyone assumes that everything in the cart—all 100 parts—are inspected, in-process on the first op. The second op is produced the same way, and then it goes to the mills. By the time it’s finished, they (the parts) have gone through all their in-process inspection, from one operation to the next, and they’re shipped to the customer.”

A 5-axis part has more complex instructions for what to check, and how often. But it, too, is inspected in-process, McGrath said. He noted that it’s rare for one of Evden’s parts to be rejected. “Most of our customers, after they’ve received a couple lots, put us on a dock-to-stock type basis, where they don’t inspect anything.”

McGrath said Evden is dedicated to on-time delivery and repeatability of production lots over a long period of time. The company uses software to manage jobs and track workflows, enabling it to provide up-to-date information on the status of any order.