Factory use by the nation's manufacturers edged down 0.1 percentage point to 79.6 percent of capacity in July, the lowest level since last November, the Federal Reserve Board reported yesterday.

The new report came three days after the board had said U.S. industrial production rose only 0.3 percentage point in July.

The reports appear to indicate that big industry's part of the national economy is moving along slowly, not growing much but not collapsing either.

Factory use, for example, was at 79.4 percent of capacity last November, rising only as high as 80.2 percent in May before declining to 79.6 percent last month.

The board earlier had reported June's rate at 79.6 percent also but revised that figure to 79.7 percent in the new report.

In contrast, the operating rate for producers of industrial materials rose 0.3 percentage point to 811/2 percent of capacity in July, "mainly as a result of a further poststrike increase in coal production," the report said.

Within manufacturing, the preliminary estimate was that the rate for iron and steel producers rose slightly more than 1 percent, although exact figures were not given.

The rate for motor vehicles and parts fell from an already abnormally low 65.9 percent to 63.1 percent in July, mainly because of a substantial decline in the output of trucks, the Fed reported.