Job Shop Looks To Future With Advanced Multi-Pallet HMC

It wasn't the easiest investment for Gaetan Jacques and his partner, Jean McCarthy. Even though they've been in business for 20 years and use some of the latest CNC equipment for precision machining of one-off prototype parts or small volume production, implementing a highly advanced horizontal machining center (HMC) and multiple palletized setup process was quite a new step for the company. But Mr. Jacques, who sells the company's expertise and manufacturing capabilities, realized that to remain in business in the highly competitive contracting services business, the company had to be more productive and flexible by committing to innovative manufacturing technologies.

JLM Precision relies on the expertise and detail attentiveness of their machinists and equipment technology to provide their customers quality parts in a just-in-time environment. Their contracting production varies from one-off prototypes to production runs for worldwide clients in the electronics, optics, food, aerospace, woodworking and nuclear industries.

The shop uses manual knee mills and lathes, for producing their own fixturing and odd jobs. CNC vertical machining centers and turn/mill centers are used for high volume parts production.

Some job shops might do one or two parts on manual lathes or mills. Mr. Jacques said they could do it better on CNC machines. It was this thinking, the need for advanced technology, and the experience of his employees with CNC equipment, that led him to invest in a Palletech manufacturing cell.

With three Mazak vertical machining centers (VMC), two turning centers and one turn/mill center already being used in their shop, Mr. Jacques and Mr. McCarthy looked to Mazak again for its most advanced technology for part production. This involved more than just purchasing a new machine tool—now they were integrating a special flexible system for manufacturing parts as productively as possible. It also meant the company had to change their way of thinking for producing parts.

In July of 1997, Mazak delivered a FH580 horizontal machining center including an eight station pallet system, one load/unload station, a 120-tool changer, special high volume chip control system and the latest touch screen controller for the pallet system.

Because the employees were already familiar with Mazak's user-friendly CNC and its operation, programming the FH580 was not a problem. The only training they needed was in the pallet operation and sequence programming.

Fixturing for the Palletech was a big change at JLM. Many of the parts they produce are mounted on tombstone fixtures which JLM builds themselves. They also use Chick clamping fixtures mounted on tombstones for high volume small parts.

With the FH580 and its standard one-degree increment table indexing, JLM could use up to four faces of a tombstone for part mounting. Multiple parts could be loaded around the four sides and even on top if needed, or several sides of one part could be cut in one setup. This capability increased spindle utilization tremendously and improved productivity.

Mr. Jacques said that with the Mazak's palletized machining cell, JLM has the versatility, capability and capacity to do different types of parts in lot sizes from one to thousands. The beauty of the palletized system is that workpieces can be loaded and unloaded while the machine is in operation. Loaded pallets are automatically transferred from the loading station to the pallet stocker or the FH580 as needed, not sequentially.

Mazak's FH580 has a 12,000 rpm, 30-hp spindle with rapid traverse rates of 1259 ipm. It has a tool-change cycle of 6.5 seconds from chip to chip. Table size is 19.7 inches by 19.7 inches with a load capacity of 2200 lbs evenly distributed. With its high speed spindle motor and rapid machine movements, production increased and more parts could be fed to the machine. Because of this productivity increase, traditional part scheduling practice was changed in the shop.

Higher volume parts are now produced on the FH580 palletized manufacturing cells instead of the VMCs. Mr. Jacques said that four or five of the pallets are designated for this type of work. The other pallets are used for one-off or very low volume parts.

A quantity of cast-aluminum electrical panel boxes that took six weeks to produce on a vertical machining center is now being done in just two weeks with the FH580.

After the operator schedules the production as the pallets are loaded, Mazak's Palletech controller automatically commands the sequence to transport the pallets to the FH580 via a guided rail transporter.

Loading stations are designed for convenient pallet loading and unloading. At the station, the pallet can be quickly indexed in 90-degree increments for easy access to all sides.

For unattended operation, JLM uses the FH580's standard tool eye. It automatically checks tool measurement and compensates for wear or broken tools by instantly updating the machining program.

Plus for increased uptime, the FH580's 120-tool changer has redundant tools. If a tool breaks or wears out, the machine will select another identical tool and prevent shut down. It will also alert the operator.

Mr. Jacques said that they are still learning how to use the special features of Mazak's Palletech system to its fullest capabilities. With this equipment, he now has the ability to pursue work that he would never have been able to bid on before because of the Palletech's unmanned manufacturing capabilities and high productivity.