TRAVERSE CITY, Mich. — When Toyota Motor Manufacturing launched production of the Lexus ES-350 in its massive plant in Georgetown, Ky., last year, the automaker invested hundreds of millions in new tooling and structures.

But plant President Wil James Jr. says the investment that paid off best was the one the company made in its 750-member Lexus work force. And as of Tuesday, he will have the hardware to prove the point; the Lexus line earned a Platinum level award for initial plant quality from J.D. Power and Associates for the Lexus ES-350 in its first year of production.

Speaking at the Center for Automotive Research’s Management Briefing Seminars here, James said Lexus team members spent 1.5 million hours training prior to launching the ES-350.

The training included weeks of studying in a library-like setting inside the plant, field trips to local Lexus dealers to speak with both salespeople and customers and the purchase of 22 Japan-built ES-350s which were taken apart and put back together several times.

“While advanced technology becomes more and more critical to our industry … at Toyota, we still believe that the single most accurate and valuable tool on our production line continues to be a highly skilled and well-trained team member,” James said.

The Lexus line also eschews air-powered hand tools in favor of quieter, more precise electric hand tools, James said.

He said the plant’s Lexus team embraced the Japanese custom of takumi, or master craftsman, in learning their processes. He said the automaker encourages team members to develop their sense of touch, training them to be able to differentiate a millimeter’s difference in fit-and-finish just by running their finger over the gap.

“We taught our team members to own their sense of touch for small tasks,” James said.