Job Shop Doubles Production With Wire EDM

At just 23 years old, Jack McGrail surrendered a steady income and partnered with a fellow machinist to jump-start a job shop in a barn behind his mother's house in Brockton, Massachusetts.

Eleven years later, that business--MIE Associates Inc.--is said to be the largest wire EDM job shop in Brockton with $1 million in annual sales.

MIE rests its reputation on its ability to machine large parts quickly using GFAGIECHilles Technologies' ROBOFIL 300 and its newest wire EDM machine with a Fanuc control, the ROBOFIL 510F, Mr. McGrail said. The ROBOFIL 510F not only cuts large parts unattended, but accelerates MIE's production because its Fanuc control is easy for CNC operators to learn and operate.

Recently, MIE machined a three inch by six inch by eight inch mold insert for a local Brockton job shop in less than an hour. Because of the ROBOFIL 510F's independent U and V axes, the mold was cut with 20 degree tapers within 0.0005" accuracies. "It cut in record time," Mr. McGrail said. The job shop that outsourced the work to MIE could not machine that mold insert that quickly or accurately without the power of a GFAGIECHilles 510F.

Mr. McGrail and his partner Michael Medeiros have come a long way since 1985, when money and space were tight and they bought their first EDM machine: a Brother HS-100, a high-speed wire EDM designed to take up little floor space but offering precision, high-speed cutting with less power.

They added more EDM machines--four EDMs between 1990 and 1993, and two more Brother EDMs in 1991 and 1994--but they didn't have continuous machining, simple programming and the ability to work on large pieces with precision until they purchased GFAGIECHilles Technologies ROBOFIL 510F (GFAGIECHilles Technologies, Lincolnshire, Illinois).

The ROBOFIL 510F, which MIE purchased earlier this year, machines multiple parts unattended, increasing MIE's productivity during the evenings and weekends. While MIE was capable of machining without operator attendance with some of the older model EDM machines, the company didn't have the technology available that would allow for unattended machining of multiple parts, Mr. McGrail said.

MIE recently machined a revision to an existing rubber mold that was nearly as big as the 510F's table travel of 16 inches by 28 inches. The 510F automatically machined multiple cavities in less than two days. No other EDM in the shop was able to handle such a large workpiece with GFAGIECHilles' accuracy and speed, he said.

In addition to opening the door for MIE to machine large workpieces, the EDM nearly doubled MIE's production ability.

Operators have been able to quickly and easily program a part for machining with the Fanuc control which is a familiar control in the industry. Many operators who use CNC equipment know how to operate Fanuc controls or can learn from the beginning with little instruction time, cutting down on the amount of time MIE had to invest to get the 510F up and running. In fact, MIE operators learned how to program and run the machine in less than two weeks, and were producing parts with little or no downtime.

Operators can load and plot programs on the Fanuc control while the 510F is running another job. "That really cuts down on time," he goes on to say. "You just put the piece in and turn on the machine."

Easy to use, the 510F also cuts parts quickly.

The ROBOFIL 510F cuts 26 square inches per hour maximum and uses regular brass wire, when cutting at a normal pace. When there is a sudden demand for a great number of parts, the 510F can be loaded with stratified wire which increases machine efficiency by up to 20 percent.

While MIE may have had modest beginnings, Mr. McGrail is confident the capital improvements--particularly the addition of the ROBOFIL 510F--are already reaping rewards for his job shop. As business continues to grow, Mr. McGrail has vowed to trade in some of the company's older EDMs and continue on the path to increasing speed and accuracy with state-of-the-art technology. MMS