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                                                                    Exhibit 31.1

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
      AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

      In connection with the Annual Report of Riviera Tool Company (the
"Company") on Form 10-K for the fiscal year ended August 31, 2004 as filed with
the Securities and Exchange Commission on the date hereof, I, Kenneth K. Rieth,
Chief Executive Officer of registrant, certify, pursuant to 18 U.S.C. Section
1350, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002,
that:

(1)   I have reviewed this annual report on Form 10-K of Riviera Tool Company;

(2)   Based on my knowledge, this annual report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, not misleading with respect to the period covered by
      this annual report; and

(3)   Based on my knowledge, the financial statements, and other financial
      information included in this annual report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      registrant as of, and for, the periods presented in this annual report;
      and

(4)   The registrant's other certifying officers and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant
      and have:

      (a) designed such disclosure controls and procedures, or caused such
      disclosure controls and procedures to be designed under our supervision,
      to ensure that material information relating to the registrant, including
      its consolidated subsidiaries, is made known to us by others within those
      entities, particularly during the period in which this annual report is
      being prepared;

      (b) [Paragraph omitted pursuant to SEC Release Nos. 33-8238; 34-47986];

      (c) evaluated the effectiveness of the registrant's disclosure controls
      and procedures and presented in this report our conclusions about the
      effectiveness of the disclosure controls and procedures, as of the end of
      the period covered by this report based on such evaluation; and

      (d) disclosed in this report any change in the registrant's internal
      control over financial reporting that occurred during the registrant's
      most recent fiscal quarter (the registrant's fourth fiscal quarter in the
      case of an annual report) that has materially affected, or is reasonably
      likely to materially affect, the registrant's internal control over
      financial reporting; and

(5)   The registrant's other certifying officers and I have disclosed, based on
      our most recent evaluation of internal control over financial reporting,
      to the registrant's auditors and the audit committee of the registrant's
      board of directors (or persons performing the equivalent function):

      (a) all significant deficiencies and material weaknesses in the design or
      operation of internal control over financial reporting which are
      reasonably likely to adversely affect the registrant's ability to record,
      process, summarize and report financial information; and

      (b) any fraud, whether or not material, that involves management or other
      employees who have a significant role in the registrant's internal
      controls.

Dated: December 27, 2004

By: /s/ Kenneth K. Rieth
    ---------------------------
        Kenneth K. Rieth
        Chief Executive Officer