After discovering mechanical defects, two power tool manufacturers have urged end-users to return a total of 204,000 circular saws and electric grinders.

Makita USA Inc., La Mirada, Calif., recalled its model 5740NB circular saw with 71/4-in. blade. The manufacturer says that the lower blade guard can become jammed. About 180,000 units exist in the field today.

Milwaukee Electric Tool Corp., Brookfield, Wis., has similarly recalled its 15-amp electric grinders with 7- and 9-in. discs. According to the manufacturer, the "on/off" switch can become stuck in the "on" position. The manufacturer estimates that 24,000 of these grinders currently are in use.

Rich Peterson, Milwaukee's brand media manager, says that his company received a couple of calls from customers, investigated and found the problem with the switch.

The U.S. Consumer Product Safety Commission announced both recalls on Dec. 19. "The consumer should not pay a single penny," says Scott Wolfson, CPSC spokesman. "The consumer just needs to go back to the place where they bought it" for repairs, he says.

Ted Banas, a Makita representative at West Loop Tool Rental in downtown Chicago, says that power tool manufacturers typically have a positive track record. Wolfson, on the other hand, says that research indicates a gradual, three-year increase in power tool recalls since 2000.