The chip modules had to be mounted on circuit boards and run through an automated solder process, which meant high temperatures and exposure to chemicals. The first modules were covered with a varnish, but the varnish became brittle and flaked. The engineers switched to a rubberized material, but the rubber expanded and caused electrical failures.
IBM's management in upstate New York became concerned. "Obviously this thing went screaming up to the top of Endicott and Poughkeepsie because [the problems] basically shut the line down," Toole recalled.
He and his team had to test out so many modules so quickly that they ended up designing a special board with a small light bulb so that they could see quickly if the electrical circuit was still functioning as it moved through parts of the process.
"We literally didn't sleep for a couple of days, running things through the process, making sure we had all the right data."
In the end, he was able to isolate the problem. The design fix included covering the module with a metal cap that would allow it to survive the process.
Based on that and other work he did, Toole and his wife were treated to dinner at New York City's luxurious Waldorf Astoria Hotel and a night in its Eisenhower Suite. He received an outstanding contribution award, including a check for $1,000 presented by then-president Tom Watson Jr. and Watson's mother.
"I might have been 26 at the time," he said.
The System/360 also marked the first time that mainframes were compatible with each other. That meant a business could buy a small system and when it outgrew it, buy a larger one with the knowledge it could still run the same software and use the same peripherals.
That presented a whole different set of challenges for IBM. "These individual plants and labs that had never worked together before now were forced to. All the interfaces had to get aligned, all the software had to be portable," Toole said.
It was a huge bet for IBM. The company invested some $5 billion to develop the System/360, equal to almost double its annual revenue at the time.
"It was just a monumental task, with everyone working on it," Toole said. "It was extremely exciting, working around the clock and through the calendar."
He's modest about the "small" role he played, but he would go on to do well at IBM. He became a lab director, a division president and eventually general manager for IBM Technology Products. His son, Pat Toole, is general manager of the IBM mainframe business today.
The mainframe was an immediate success, Pat Toole Sr. said. "We were not only sold out for a couple of days, we were sold out for a couple of years."
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