Washington investors Steven M. Rales and Mitchell P. Rales told the Securities and Exchange Commission yesterday that they have offered to buy Scott & Fetzer, a Cleveland industrial and educational conglomerate for $60 a share -- a deal worth about $396 million.

The Rales brothers told the SEC that two firms they control, Danaher Corp. and Equity Group Holdings, own 432,800 shares of Scott & Fetzer, more than 6.5 percent of the 6.6 million shares outstanding.

In a letter included in the SEC filing and addressed to Ralph Schey, chairman of Scott & Fetzer, Steven Rales said, "We believe that a cash merger at $60 per Scott & Fetzer share would be very attractive to all parties."

There was no immediate comment from Scott & Fetzer.

In addition to manufacturing Kirby vacuum cleaners and other consumer and industrial products, the Cleveland firm distributes the World Book Encyclopedia.

Rales' letter to Schey noted that Danaher had recently raised $150 million in a public offering managed by the First Boston Corp. and said that "a significant portion" had been earmarked for acquisitions, and could be used for a Scott & Fetzer buyout. He said he was confident that the rest of the funds would become available through additional borrowings.

Rales told the SEC that Danaher and Scott & Fetzer "have discussed the possibility of such an acquisition. However, there is no understanding or agreement between Danaher and the company as to such a transaction."

Indeed, he said, after further discussion, Danaher might change the terms of its offer or withdraw it.

Scott & Fetzer has been the object of buyout talk since April of 1984. Chairman Schey first offered $50 a share for the company. After that, arbitrageur Ivan F. Boesky offered $60 a share but was turned down.

Later Kelso & Co., an investment bank associated with employe stock ownership plans (ESOP), offered $62 a share but intervention by the Department of Labor caused General Electric Credit Corp. to withdraw support that was essential to the deal. The Scott & Fetzer board of directors formally terminated the Kelso talks on Sept. 5.