Underscoring its strategic commitment to high technology and aerospace markets, Fairchild Industries Inc. said yesterday that it had agreed to sell both its consumer fastener and hardware manufacturing units for approximately $35 million in cash.

The company said it would sell VSI Fasteners Co. -- which manufactures fasteners such as screws, chains, ropes and cords -- to a group of investors headed by company founder Phil Furst for $25 million. The VSI Hardware Co., which manufactures and imports bathroom fixtures and locksets, will be sold to Charles H. Sweetman, the unit's president, for about $10 million.

The two companies represented the consumer products side of the VSI Corp., the California company that Fairchild acquired in 1980 for $280 million.

The VSI group, which manufactures most of Fairchild's commercial industrial products, accounted for roughly half of the company's pretax profits in its most recent fiscal year.

The parts of VSI disposed of "were consumer-oriented businesses that won't fit into our high-technology strategy," said a Fairchild spokesman. Fairchild will retain the commercial industrial production operations of VSI.

The company has publicly stated that other "small manufacturing operations" are potential candidates for sale, but the spokesman declined to elaborate.

However, one analyst who asked not to be identified suggested that Fairchild possibly could place its Cardkey Systems Division, which manufactures security management and access control systems, and the Tubing Seal Cap Co., which produces seamless doorknobs, on the market.

"Times are tough at Fairchild," said the analyst, who noted that the company lost 82 cents a share last year on revenue of $899 million. "This year, they'll be lucky if they break even." Fairchild's 1985 revenue should approach $1 billion.

Fairchild has chosen to emphasize its aviation business and focus on developing its American Satellite Co. business telecommunications partnership and its bid, through a venture called Leasecraft, to build a spacecraft that could be used as a vehicle for companies interested in exploring the commercial potential of outer space.

The company also may seek to negotiate an agreement to reduce its financial investment in a partnership with Sweden's Saab corporation, which currently is producing the Saab Fairchild SS340 commercial passenger plane. The venture currently is a 50/50 split.