Jig Grinding Up from the Farm

Don't be misled: We're not talking about taking serene cattle farms in the hills of Pennsylvania and turning them into successful mega-metalworking enterprises with a depth and breadth of process and technology that challenges imagination. What we are talking about is a tool and die company that started on a farm and moved a few miles down the road and grew to a hundred- million dollar operation employing a 700-plus top-flight workforce. The farm still exists and stands testament to technology and to constant learning

According to Bill Jones, president, Penn United Technologies, Inc., the company has 11 different sites, seven on the main campus and the rest within a five-mile radius. Their customer base is in electronics, automotive, medical, aerospace, fluid handling and so on. They work in tool steel, stainless, carbide, cast iron, aluminum and brass.

The company's customers consider it a "precision manufacturer" in all its areas of expertise (of which there are many). "If you look over our equipment list, you can see why," Jones said. Each facet of our business - die, stamping, plating, assembly and even our production work (about 25 percent of annual business volume) - is very high end. We excel at working with the closest tolerances. I say this without exaggeration, because we've always bought leading edge technology - not necessarily targeted at a job in particular, but because of what we might learn from acquiring it and how that might enhance our strategy in one or more of our existing areas of expertise."

And thus it was with one of their latest acquisitions, a Hauser S35-400 jig grinder made by Hardinge Kellenberger (Elmira, NY). Jones explains that even though they have an army of jig grinders (the company has nearly 300 grinders, close to 30 of which are jig grinders), they've from time to time looked at Hauser jig grinders. Early on, Hauser prices were on the high side, especially if you were buying the machine for a specific application, which Jones thinks isn't all that likely: there are too many other jig grinders for single application work.

"It used to be - and not too long ago - that we felt it cost too much money to own a Hauser. But that's all changed. Hauser has kept its technology moving forward very rapidly, and while other jig grinder manufacturers have raised their prices without meaningfully increasing capabilities, Hauser is becoming more advanced and easier to use - without raising prices. So, at IMTS '06 we bought one."

Jones said that within three weeks of the close of the show, the Hauser was being installed at their plant, and within five weeks Penn United operators were running parts, starting out with one-at-a-time small parts and eventually getting to the point of loading up the table, pushing the start button and walking away.

Early Results
The Hauser S35-400 is the only jig grinder at Penn United that uses the HI-CUT system - grinding with oil as a lubricant/coolant. Jones said that you really can't grind carbide with a water-based coolant, as the water leaches the cobalt out of the carbide. The other choice, which is the main choice of lubricant in jig grinding at Penn United, is air. Generally when grinding carbide in a dry application (using air as the lubricant), the wheel is the weakest link. If the wheel holds up, the air turbine spindle could become a problem. But with the HI-CUT system, which is an oil chiller/fire suppression oil coolant system, you don't have to worry about wheel or spindle failure.
 

"Last week," he said, "we were roughing carbide, and it was so hard that we couldn't see what was going on inside the machine with all the smoke and mist. I got worried. I called Hardinge and told them of my concern with the smoke, and they told me to relax, that there was nothing to be concerned about. In fact, if it weren't smoking then we weren't doing something right. So, from that perspective, I think that how you remove a lot of material is a little different than what we've been used to. Our guys are starting to adjust to this, and the Hauser is proving a great performer in removing really hard, tough material."

Two of the biggest advantages, Jones said, are the tool life and the finishes. "Not only is the tool life better because we're using fewer tools - as in a single wheel to rough and finish. Before we had to use a low-grit roughing wheel and a high-grit finish wheel. Now we can use a high-grit roughing wheel and go start to finish with one wheel. Obviously, if we're only using a single an apparent savings - in this case 60 percent to 70 percent.

Another area where Jones is seeing a distinct advantage is in cycle time reduction. As an overall average, he's seeing reductions of 30 percent to 35 percent, "and we know we're not doing everything to full efficiency," he said. "We've still a long way to go learning all of what the Hauser can do, but to see these initial cycle time reductions as remarkable."

Assumptions Aside
The Hauser is being used to grind carbide and steel, primarily. On the carbide side they're grinding cutting punches for knives, roughed and finished right on the Hauser. "In the past," Jones said, "these parts would go to a wire EDM, and the form would be finished there. Not now with the Hauser. There have been more than just a handful of jobs that used to be done via EDM, but no more. The Hauser has moved those jobs out of the EDM picture.

Jones notes that in the case of which is better - grinding, EDM or high-speed milling - it's not a case of one technology being superior. Each has its place, he said. The question isn't which technology is better than the other; the question is which is the right one for the application.

"As each new technology comes out," Jones said, "we evaluate: Is it time to move this application from one type of operation or technology to another? Some we move, some we don't. Obviously, the Hauser has introduced us to a more technologically advanced way of grinding."

As an example, Jones said that when they purchased the Hauser they had one or two jobs in particular in mind that they felt would be most ideal for the machine. "However," he said, "after learning more about the Hauser and seeing some of the jobs switch around, we realized that we could greatly many jobs that we did in the jig grinding department. So much so, that the tedious jobs that nobody wants now end up on the Hauser."

Setup/Changeover, Time/Money
Jones reports that the Hauser is so unlike other jig grinders that they're learning something new every day. "The machine has a 12-station ATC, a probe system and an electric spindle that's a breed of technology that we'd never seen in jig grinding until the Hauser," Jones said.

Regarding the toolchanger, Jones said that right now they're working on having enough tool holders to have wheels already mounted so they just place them in position - less than five minutes per tool. The probe, which sits in one of the 12 pockets of the tool changer, allows them to reduce time by half on basic setups.

"I've been working with Hauser on a few applications involving the probe in toolchanging where we actually pick up the part with the probe," said Jones. "This would result in 50 percent to 75 percent faster setups."

According to Jones, the spindle on the Hauser is something they've not seen on any other jig grinder. "The others," he said, have air-operated spindles. To go from 8000 RPM to 60,000 RPM you'd need to use three different work heads. The electric spindle will go from 7000 RPM to 70,000 RPM - with a single head. What's nice is that at 7000 RPM you have the same torque as you have at 70,000 RPM. With the air spindle, at 8000 RPM a guy with well- calloused hands can simply grab the wheel and stop it, the torque is so low. When grinding carbide with the electric spindle, the work head is no longer a variable factor.

A Question of Precision
So far, Jones said, they've proven they can hold 0.000040" positional accuracy - that was a position of seven holes precisely 0.000040" of each other. That sounds amazing from a machine capability point of view, and Jones adds, "We have very good inspection equipment. Once you take the part off and inspect it, you've got to be certain that your inspection equipment is capable of "seeing" differences that small. If your machine is that good - which the Hauser is - but your inspection tools are not, you can be out of tolerance by a very small amount very quickly."

Jones said that one test for precision is in tool and die work. "We work for some razor companies that make components, and we're trimming materials that are 0.0008". When we get down to materials that thin, our punch-to-die clearance may be less than 0.0001". If you want your die clearance to be 0.0001" or less, then you need your positional tolerance to be 0.000040" or 0.000050". When we get into materials that thin, we manufacture the components to the closest tolerance we can to make sure that the dies have perfect alignment and will run well once put together. If you don't have the alignment just right, you either have chipping or premature wearing. The alignment in the die business is extremely crucial.

Running Unattended
"Programming expertise is becoming more invaluable as technologies have a higher and higher degree of sophistication," Jones said. "For instance, this weekend the operator worked from lunch on Friday to about 4:00PM programming a couple of parts. He hit the start button and the machine ran until about 6:00 PM on Sunday, about 36 hours unattended."

Jones said his programmer will work approximately a quarter of the day programming and doing setup, and the remainder of the day and most of the evening the machine is running on its own. "But there are a number of machines that should be able to run around the clock" Jones said - "good EDMs and a lot of CNC equipment. If you're a good programmer, you should expect the machine to run around the clock. If you can't, you've got the wrong machine. And that's a shame, because you've spent all this money, you've got a good programmer, but the machine's just not sufficiently rigid or accurate to run unattended."

Advances in technology change entire paradigms, Jones reflects. Not usually in a sweeping way, but in pockets, here and there. He said he's got a particularly unique viewpoint on technology impact. Penn United is so diversified, that he can look out over the enterprise and see the impact of technology on this area, then on another area, then yet again on another area.

"As these advancing technologies are changing, they're definitely putting more pressure on having good programmers," he said. "When the toolmaker was making everything by hand, you needed a toolmaker with manual finesse. Now, the education of the toolmaker has to follow the technology. In today's industry, a good programmer is as valuable as an experienced toolmaker. Because you need to capitalize on your investment in new technology."

This Changes Everything
Jones said that regarding many of the parts of the company's day-to-day operation the Hauser has changed everything. Everything his jig-grinding operators have been trained in for the past 25 to 30 years is now open to reevaluation. Hauser has taken all that and rethought it. Much of the knowledge that his operators gained thus far in their careers has just been flipped up 180¡ resulting in a totally new way of jig grinding and thinking about jig grinding.

Jones: "The Hauser has completely changed in a very short time how we do things in the department and, actually, in a few of the related departments. We were talking about some of the wire EDMs, and we've changed some of the EDM jobs to the Hauser. We're seeing the impact the Hauser is ushering in, because we keep learning more and more of its capabilities and are more and more impressed every day."

Jones has only positive comments on the service he's gotten from Hardinge. "You've got to keep in mind that this was a show machine, and it had everything on it, and as you might imagine, there were a few glitches at first, primarily software. And their customer service - I was hoping to get service like this, but I wasn't expecting it to be this good. They would drive someone down the minute I called Elmira. Twice they did that, and it's a five-hour ride for them. They'd get here, figure out and show us the problem, fix it and go back home. Their customer service is absolutely outstanding, and this is coming from a guy who's bought a few machine tools and systems over the years."

Assessing the Hauser
Jones said, "It's far too early for me to make an assessment of the Hauser S35-400. What do we know? We know we're getting phenomenal performance. We know it's very rigid and incredibly fast and totally accurate. We know we can hold positional tolerances in the millionths. We know it will run around the clock. We know it's changed many of our presumptions about grinding, EDM and other technologies. We know we get outstanding service. We know there will probably be more Hausers at Penn United. And we also know that we have a great deal of learning yet to do. There's just so much to know, about the machine, about how best to use it. I know we're more and more impressed every day.

"If you really want an assessment, I'd say get back to me in a year or so. Or, go out and buy one yourself. I'd love to have someone to compare notes with."

- As told by Bill Jones, president, Penn United Technology, Inc.

For more information contact:

Hardinge Inc.

P.O. Box 1507

Elmira, NY 14902-1507

800-843-8801

Fax: 607-734-8819

www.hardinge.com

E-mail: info@hardinge.com

Sidebar:

Down on the farm
Bill Jones, president, Penn United Technology, Inc., explains it this way: "The company started in 1971 in a three stall garage referred to as the "chicken coop" back on my father's farm. My father, Carl Jones, along with Bob Becker and Jack Barton

were the three men that started Penn United. It grew from there on the farm and had close to 50 employees, before we moved to what we call our main site today. That was in 1978.

"The farm is really what we refer to as our incubator. We started many other businesses and grew them out on that site. For example, our plating department started around 1985 on that site. We decided to get into plating to help our stamping facility because some customers began asking us to do precious metal plating. Since we did a lot of their stamping, it made sense, so we launched the new business back at the farm.

"When we purchased our carbide facility in Tennessee, we moved it to the farm in 1996. We grew our carbide business on that site until we built a building in Saxonburg. We still use the farm as a warehouse and special projects site. The original building that was a three stall garage doubled, then tripled in size. We started our stamping facility on that site, and at one time had a large 25,000 sq. ft. grinding area on that facility.

"It's still functioning. My father used the farm to support himself when he started Penn United. For a while he didn't take any money from the business, and he used the farm actually to sustain him through the first years, beef cattle and all - which he still has on the farm. It carried him through the first couple of years while he was learning the business."