Leader of Local S6 of the Machinists Union, now in its seventh week on strike, said negotiations with Bath Iron Works officials continued to make progress Tuesday, but the conversation “broke down” when the crux of the disagreement between the two parties was brought to the table. Kathleen O’Brien / The Times Record

BATH — Contract negotiations between Bath Iron Works and its largest union, Local S6, made some headway Tuesday, but union leaders said progress stalled when more contentious issues were brought to the table.

According to a statement from the union, the two parties, with the help of a federal mediator, tentatively agreed on three more contract articles on Tuesday, bringing their total to five articles.

The proposed contract from the company includes 52 articles. It’s unclear how many of those articles the company and the union plan to review and debate.

Despite the progress, union leaders wrote negotiations “appear to be breaking down as the bigger issues are being addressed.”

The union did not describe what articles were agreed upon Tuesday or what brought the discussion to a standstill.

The primary disagreements that sparked the strike were the company’s proposed changes to how it can hire subcontractors and proposed changes to seniority privileges, such as shift times and assignments.

The Federal Mediation and Conciliation Service, brought in to help spark communication between the two, confirmed in a statement Wednesday the company and union agreed on three additional articles, and negotiations will continue.

“Though [Federal Mediation and Conciliation Service] cannot comment on the substance or status of their specific negotiations, FMCS mediators are working with the parties to resolve the issues that divide them,” the mediator’s statement read.

The strike, now in its seventh week, began on June 22 after the Machinists Union Local S6, which represents 4,300 of the shipyard’s 6,800 workers, voted against the company’s “last best and final” contract offer.

In Monday’s meeting, the two parties agreed not to change company holidays and the union gained “the ability to jointly develop merit raise criteria.”

“This helps the union to assist mechanics that are not first-class that display the skill to progress forward without having to wait for 1,000 hours,” union officials wrote Tuesday.

In the company’s proposed 3-year contract, the ability to determine merit raises was solely a company right.

David Hench, BIW spokesman, declined to comment Wednesday.