ABOUT 200 members of the carpenters union converged on the Philadelphia Auto show at the Pennsylvania Convention Center on Saturday to protest their lack of a contract with the center's management.

Converged is probably too nice a word. Invaded is more like it.

The union says it was just exercising its right to free speech, handing out fliers to people attending the big show, which drew 60,000 people on Saturday.

The center's management - citing eyewitness reports and surveillance videos - said that the carpenters came in waves, beginning about 12:30 p.m., and engaged in repeated acts of harassment and vandalism: stuffing auto interiors with leaflets, stealing fuses and knobs on dashboards, removing oil caps and ripping out wiring.

The evidence that management presented at a quickly called hearing on Sunday was enough to convince Common Pleas Judge Maria McLaughlin, who issued a restraining order on Sunday banning further protests inside the center until after the auto show leaves today.

This is only the latest protest by the carpenters at the center, but it was the most intense and certainly the dumbest.

The carpenters and their leader, Edward Coryell Sr., are furious because they no longer work at the center. Their tasks were taken over by four other unions, who still are working because their leaders signed a new agreement with the center's management last spring, agreeing to work-rule changes to make life easier for exhibitors and convention agents. The union's reputation for labor hassles was killing business at the center and something had to be done.

Coryell and a unit of the Teamsters Union refused to budge and now they are on the outside looking in - without a contract and without any work at the center.

Coryell and the Teamster president say they were ready to sign the agreement, but were "tricked" by the center's board. That's an odd claim. As their chief negotiator, Coryell is paid $236,000 a year by union members not to be tricked. Plus, Coryell sits on the board of the center and was present when decisions were being made about the steps that management would take. He can say he didn't like them, but he can't say he didn't know about them.

The unions appealed to state and federal labor-relations boards, but lost both cases in rulings.

Since the carpenters left the house, business at the center has revived, new conventions are signing up to meet here and even ones who vowed never to return are reconsidering. That's good news for the city, where we depend on a thriving leisure and hospitality industry for thousands of jobs.

A thriving center means construction of new hotels, renovations of older ones, plus more building projects in general. And who will work on these projects? Union carpenters.

Which makes the latest protest dumb. To "punish" the center, they are now engaging in goonish protests designed to drive business away, which will only shrink the number of union jobs outside the center.

Such tactics call to mind the recent criminal shenanigans of the Ironworkers Local 401. Last month, after nine of his ironworkers pleaded guilty to conspiracy, extortion and other offenses for their actions on nonunion job sites, Ironworkers chief Joseph Dougherty was found guilty of using arson and violence.

No one has accused the carpenters of physical violence . . . except for the black eye that Coryell just gave to himself and his members.