The union trying to organize the 7,000-employee Boeing plant in North Charleston has opened an office on Dorchester Road and plans to hold its first meeting Thursday.

The International Association of Machinists and Aerospace Workers is trying to rally workers in the 787 Dreamliner assembly plant to join the union in a right-to-work state where Gov. Nikki Haley constantly says unions are not welcome.

"It's an ongoing organizing effort," said IAM spokesman Frank Larkin. "We still maintain contact with several hundred employees who maintain contact with us. There is enthusiasm and, in some cases, strong enthusiasm for collective bargaining in the facility."

He said the effort is early in the process, but the meeting is meant to educate interested Boeing employees.

"It's important that they know their legal rights," Larkin said.

To organize the plant, he said, 30 percent of eligible employees must sign cards as the legal minimum to call for a vote. Then, a simple majority must vote in favor of unionizing the local Boeing facility.

The union meeting is closed to the public because Larkin said, "Given the political atmosphere in South Carolina, we would want to protect the privacy of the employees."

Boeing and the Machinists have crossed paths before at the site.

When the Chicago-based aerospace giant bought its North Charleston fuselage plant from a supplier in 2009, some of the workers were represented by the IAM. The local membership voted to sever ties with the union that same year.

Less than two months later, Boeing selected the 264-acre campus at Charleston International Airport as the site for a second line to assemble the 787 Dreamliner.

The IAM has been looking to recruit the work force ever since, and Boeing has tripled its footprint near the airport for future expansion.

The union later complained to the National Labor Relations Board that Boeing built the South Carolina plant in retaliation for past strikes in Washington state. The agency filed a lawsuit on the union's behalf in 2011, but the high-profile case was eventually settled.

Boeing has steadfastly been against the union entering the plant.

"As we've said over the past four years, we want to work directly with our employees and we're continuously working on keeping Boeing South Carolina a place where teammates have a voice and can speak for themselves without having to rely on a third party to speak for them," spokeswoman Candy Eslinger said. "We're very proud of what our teammates have accomplished here in South Carolina by collaborating and working together, and we don't believe a union is in the best interest of our teammates, our business, our community nor our state."

Reach Warren L. Wise at 937-5524 or twitter.com/warrenlancewise.