EXHIBIT 32.1

    CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

                  In connection with the Quarterly Report of Fansteel Inc., a
Delaware corporation (the "Company"), on Form 10-Q for the quarter ended March
31, 2006 (the "Report"), as filed with the Securities and Exchange Commission on
the date hereof (the "Report"), Gary L. Tessitore, as Chairman, President and
Chief Executive Officer of the Company and R. Michael McEntee, as Vice President
and Chief Financial Officer of the Company, each hereby certify, pursuant to 18
U.S.C. SS. 1350, as adopted pursuant to SS. 906 of the Sarbanes-Oxley Act of
2002, that to his knowledge:

      1.    The Report fully complies with the requirements of section 13(a) or
            15(d) of the Securities Exchange Act of 1934; and

      2.    The information contained in the Report fairly presents, in all
            material respects, the financial condition and result of operations
            of the Company.

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging or otherwise adopting the signature that
appears in typed form within the electronic version of this written statement
required by Section 906, has been provided to Fansteel Inc. and will be retained
by Fansteel Inc. and furnished to the Securities and Exchange Commission or its
staff upon request.

Dated: May 12, 2006


                                  /s/ Gary L. Tessitore
                                  ---------------------
                                  Gary L. Tessitore
                                  Chairman of the Board, President and Chief
                                  Executive Officer


                                  /s/ R. Michael McEntee
                                  ----------------------
                                  R. Michael McEntee
                                  Vice President and Chief Financial Officer