U.S. machine tool orders rose 46.2% in October from the previous month to $267.3 million, the National Machine Tool Builders Assn. said. The report apparently shows that Oct. 19's stock market collapse did not scare businesses from ordering tools for their factories. Orders in September were revised slightly to $182.9 million from $183.2 million. The association also said October orders were up 48.4% over those made in October, 1986. The backlog of orders in October was $1.09 billion, off 5.6% from the revised September backlog and 10.8% below the backlog in October last year.