February • March 2007 • Vol. XXV No. 3 • An Arnold Publication

Home Page

Tight Tools. . .Tight Tolerances
 Hard milling is a Way of Life for an Arizona Company.

Tempe, AZ’s Tech Mold, Inc. produces complex molds with as many as 1,500 parts, all of which have to function perfectly, according to company president, Bill Kushmaul.

“Our customers depend on us to put a huge million-dollar mold in a press and run it for nine months to a year without any problems,” he says. “and to achieve this, every component must be made to the ultimate tolerance possible. Many times we work in three- and four-micron tolerances. As a result, we always look for ways to eliminate variation.”

Key to Tech Mold’s strategy is its machine tools.

“If a machine tool adds variation to our process, it makes it harder for us to service our customers,” Kushmaul explains. “So we look for vendors, like Makino, who are committed to providing us with excellent machine tools.”

Changing With The Times

Kushmaul moved to Tempe, Arizona, from Dayton, Ohio, in 1970, and went to work for a company called Tech Plastics. Together they formed Tech Mold in 1972. The company did well in the 70s because of a tremendous demand for plastic molds.

But Tech Mold couldn’t compete with the shops back east on the simple cavity work, so the company moved on to more complicated, higher cavity molds after recognizing a need in the medical marketplace for high-cavitation, ultra-precision production tooling.

Subsequent growth in the medical market during the late-1970s helped Tech Mold develop its capabilities and expand into the high-volume packaging and technology markets. Today, this Arizona company is a recognized leader in the manufacture of ultra-precision, high-cavitation injection molds for customers in the medical, packaging and technology markets worldwide.

Together, the company’s 80 employees offer integrated capabilities in design and prototyping, production tooling, contract molding and final assembly, taking customer’s programs all the way from concept to commercialization.

Valued Partnership

Tech Mold is no stranger to Makino.

“Tech Mold has always been a value-driven company,” says Kushmaul. “For the last 35 years we’ve told our customers that value pays. And our relationship with Makino has been a valued relationship.”

Tech Mold early on replaced what Kushmaul called a throw-away machine with the Makino a51 horizontal machining center.

“The a51 opened up new possibilities for us,” he says. “It allowed us to leave less stock for after heat treat operations, and it enabled us to better maximize our existing tooling. We also had rigidity problems with the prior machines. We couldn’t really optimize our tool paths because we’d get a lot of tools that would chip and break and we couldn’t hit it as hard as we wanted to. With the a51 we were able to optimize our speeds and feeds and get better tool life.”

The a51 saved in other ways, too.

“We’re probably knocking 20% off of our cycle times with the a51 before heat treat, and we’re leaving less material,” says Jeff Renner, CNC operations manager. “In addition, the a51 gives us more after heat treat potential because it will hold the tolerances and we can do some finish work on it, which we couldn’t do with our prior machine.”

Adding Capabilities

When Tech Mold needed additional hard milling capabilities to supplement work they were doing on their Makino V55 vertical machining center, they again looked to Makino and purchased a V33 vertical machining center.
“Before getting the V33, we had been using the V55 to hold really critical floors,” says Renner. “We also used it to do some high-speed milling before heat treating, and for some finish milling after heat treat. It’s really good at removing material very accurately and very quickly. It became a popular machine. We decided on the V33 because we could go to a higher rpm spindle.”

“We are doing things now on the V33 that we used to jig grind,” he adds. “more and more work is coming to this machine. Now both the V33 and V55 are being used on a regular basis.”

Cycle Time Improvements

“Our operators tell me that with the V33 they are running 30 percent faster speeds and feeds and are able to maintain accuracies,” Renner says.

This was illustrated on a prototype medical component Tech Mold was working on.

“This is a medical container device—a two piece cavity device with threads on it,” says Renner. “Two slide faces come together and form threads around the outside diameter of the part and split open to allow for the release of the part. And then when the mold closes it has to shut off top and bottom so that the thickness in the middle is the inserts.
“Both sides get machined. It has very close tolerance— the total thickness can’t vary more than two-tenths. It’s made of H13 (50-52 Rockwell) steel. It has a 10° contour, conical surface. There is a two-tenths window on tolerance. And the floor has two-tenths depth.”

“Typically we would have finished the floor and would jig ground the conical shutoff,” he adds. “But because of the capabilities of the Makino machine, we are now able to finish the whole thing and hold the same tolerances - getting as good of a surface finish as when we were jig grinding it—only in about 30 percent of the time it used to take us to jig grind.”

Eliminating Benchwork

“With the V33’s higher spindle speed, on some of the things that we are doing now on the V33 we save as much as a 70% reduction in cycle times, compared to when we previously did jig grinding,” says Kushmaul.

“We are required by our own company standards to completely finish everything without hand work. Even if it has to have a ten-thousandths radius; we machine it on. We require the machine tool to do all the work—every single smallest bit of detail. That gives us our own changeability.”
“Because we do no bench work, the Makino machine made it easier for the operator to achieve the required tolerances,” explains Renner.

Enhancing Tool Life

“We get from 30-50% better tool life on the V33, compared to some of our other machines,” Renner says. “We save a lot of money there because of the rigidity of the machine. We also save a lot on tooling costs by getting a better insert life, better carbide end mill life, etc.”

“Makino machines have absolutely driven costs out of our operation,” adds Kushmaul. “We are doing things that traditionally were done by other machining methods and were longer procedures.”

Now A Way of Life

“Makino has helped us accept hard machining, rather than having to do grinding or EDMing,” says Kushmaul. “So the more hard machining we do, the better we get. The faster we get, the more competitive we are.”

Hard machining is a now a way of life at Tech Mold.

“Most machines, including jig grinders, don’t do a good job pulling a real close accuracy on bottoms,” says Kushmaul. “You grind or machine it. You deal with the spindle growth, cutter wear and pressure on the spindle. So when you get down into two to three microns and you are trying to hold a two or three micron depth on a large floor, that’s where cheaper machines fail. The Makino V33 and V55 have proven to be our best machines for holding hard-milled depths.”

“Makino brought to the table a much more complete solution to our problems,” he adds. “For example, spindle growth is very important to us, and Makino had perfect mapping on the spindle. Today it is unmatched by any machine we have in the company. We can machine all day within our tolerances and our other machines just can’t match that accuracy.”

Beating Foreign Competition with Quality

“We are very knowledgeable about multi-cavity tools, and we provide a great product,” says Kushmaul. “In the last four to five years, there has been a lot of downsizing with our customers moving to China. People are trying to figure out how to make a mold cheaper and faster.

“I think one of the advantages of Tech Mold is that we have been able to maintain a high standard of quality and still get the delivery time down and the cost reasonable.”

“We do an extensive amount of planning when we build our molds,” says Kushmaul. “Having a machine that’s reliable with excellent cut times helps us do a better job of scheduling through the machine. We know that Makino is going to be able to do it in a certain period of time and not disappoint on the speed. Having their machines in our shop brings us the ability to better schedule our jobs.”

High Standards, High Morale

Several qualities of the Makino machines have really stood out at Tech Mold.

“The accuracy of the Makino machine has most impressed us,” says Renner. “Sometimes it’s hard to believe just how deadly accurate and how stable those machines are. Our operators chomp at the bit to get on those machines. They love to run them.”

“Our Makinos go a long way toward morale out there,” agrees Kushmaul. “Our employees have the confidence that they are going to be able to hit the numbers without jumping through hoops.”

In addition, Tech Mold is now able to cut harder materials on the Makino vertical and horizontal machines.

“The 54, 56, and 58 Rockwell parts traditionally require a very good spindle and good tools. Today we are able to get finishes on the Makino comparable to grinding— even on those harder surfaces—and still do it with enough production life. They don’t eat the cutters like other machines,” says Kushmaul.

“In fact, we’re finishing parts on the machines up to 60 Rockwell with quite a bit of success,” says Renner.

Strong Support

“We are 100 percent committed to exceeding even the most demanding of our customers’ requirements,” says Kushmaul. “Tech Mold’s ability to manufacture steel ‘to the numbers’ is unsurpassed. When you buy a Tech Mold, you’re not just buying a piece of steel. You’re buying a single-source solution, from design to engineering to mold startup, and beyond.
“Vendors like Makino bring their knowledge of the industry to our business. They are there when we need them, and they try to help us with our problems, not just providing standard solutions. They listen to our specific needs and find a quality solution.”

“The technical support from Makino has been very impressive,” agrees Renner. “They did a phenomenal job and have been incredibly supportive. When we were initially looking at the machines, someone from Makino came and helped us go through our options making sure they understood what we were trying to achieve, and they made sure we got the options we needed and didn’t overlook something.”

Installation went smoothly. “We were up and running quite efficiently,” says Renner. “Up-time has been excellent. And the machines have been incredibly reliable.”

“With the track record we’ve had with Makino machines, I think we will have our partnership for many years to come in the machining area,” says Kushmaul.

In fact, Tech Mold's success with Makino prompted them to purchase the very first Makino V99 vertical machining center to be installed in the United States. The company anticipates exploring the accuracy of this new V99 to produce the same hard milling, tight tolerances they have grown accustomed to providing. Their customers have come to expect it.

—30—

 







Tech Mold now uses a Makino V33 to produce parts they used to jig grind.

 

 

 

 


 

 

 

Tech Mold has reduced cycle times by using a
Makino a51 horizontal machining center.

Mold work being cut on a Makino V33.