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                                   EXHIBIT 4.3


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      SEVENTH AMENDMENT AND WAIVER TO AMENDED AND RESTATED CREDIT AGREEMENT

         This Seventh Amendment and Waiver to Amended and Restated Credit
Agreement (the "AMENDMENT") dated as of May 1, 2000 among Atchison Casting
Corporation (the "BORROWER"), the Banks, and Harris Trust and Savings Bank, as
Agent;

                              W I T N E S S E T H:

         WHEREAS, the Borrower, Guarantors, Banks and Harris Trust and Savings
Bank, as Agent, have heretofore executed and delivered an Amended and Restated
Credit Agreement dated as of April 3, 1998 (as amended through the Sixth
Amendment thereto dated as of February 15, 2000, the "CREDIT AGREEMENT"); and

         WHEREAS, the parties hereto desire to amend the Credit Agreement as
provided herein;

         NOW, THEREFORE, for good and valuable consideration the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree that the
Credit Agreement shall be and hereby is amended as follows:

         1.       The definition of "DOMESTIC RATE MARGIN" appearing in Section
1.3(a) of the Credit Agreement is hereby amended in its entirety and as so
amended shall read as follows:

                           "DOMESTIC RATE MARGIN" means 0.75% per annum.

         2.       The definition of "EUROCURRENCY MARGIN" appearing in Section
1.3(b) of the Credit Agreement is hereby amended in its entirety and as so
amended shall read as follows:

                           "EUROCURRENCY MARGIN" means (i) 2.25% per annum to
                  and including May 31, 2000 and (ii) 2.50% per annum
                  thereafter.

         3.       Section 1.14 of the Credit Agreement is hereby amended by
deleting the date "APRIL 30, 2000" appearing therein and inserting in its place
the date "JUNE 30, 2000".

         4.       Section 7.6 of the Credit Agreement is hereby amended by:

                  (a)      deleting the word "AND" at the end of clause (j)
         thereof;

                  (b)      adding new clause (k) reading in its entirety as
         follows:

                           (k) COMMITMENTS. Promptly (and in any event within
                  three Business Days) after any Responsible Officer receives a
                  written commitment from any lender or lenders to advance
                  Funded Debt to the Borrower or any Subsidiary, a copy of such
                  commitment; and

                  (c)      re-lettering clause (k) as clause (l).


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         5.       Schedules 5.2, 5.6(a) and 5.13 to the Credit Agreement are
each hereby amended in their entirety to read as Schedules 5.2, 5.6(a) and 5.13,
respectively, attached to this Amendment.

         6.       The Borrower has informed the Banks that the Borrower has not
been in compliance with Section 7.15(f)(i) of the Credit Agreement from time to
time after January 28, 2000. The Borrower has requested that the Banks waive
compliance by the Borrower with Section 7.15(f)(i) for the period commencing
January 28, 2000 through and including July 1, 2000. Accordingly, the Banks
hereby waive compliance with Section 7.l5(f)(i) of the Credit Agreement by the
Borrower for the period commencing on January 28, 2000 through and including
July 1, 2000.

         7.       The Borrower represents and warrants to each Bank and the
Agent that (a) each of the representations and warranties set forth in Section 5
of the Credit Agreement (as updated pursuant to this Amendment) is true and
correct on and as of the date of this Amendment as if made on and as of the date
hereof and as if each reference therein to the Credit Agreement referred to the
Credit Agreement as amended hereby; (b) after giving effect to this Amendment,
no Default and no Event of Default has occurred and is continuing; and (c)
without limiting the effect of the foregoing, the Borrower's execution, delivery
and performance of this Amendment have been duly authorized, and this Amendment
has been executed and delivered by duly authorized officers of the Borrower and
Guarantors.

         8.       This Amendment shall become effective upon the satisfaction of
each of the following conditions precedent:

                           (a)      the Borrower, each Bank that has a Temporary
                  Commitment Percentage, and the Agent shall have executed and
                  delivered this Amendment and the Guarantors shall have
                  executed the consent attached hereto;

                           (b)      the Agent shall have received confirmation
                  from its Canadian counsel that all steps necessary to perfect
                  the Collateral Agent's security interest in the Collateral
                  granted by the Canadian Security Agreement have been
                  completed;

                           (c)      The Agent shall have received (i) for the
                  PRO RATA account of the Banks based upon the amount of each
                  Bank's Commitment (whether used or unused) on the date hereof,
                  a non-refundable amendment fee equal to 0.10% of the
                  Commitments and (ii) for its own account, a fee equal to 0.05%
                  of the Commitments; and

                           (d)      The Agent shall have received for the
                  account of the Banks such other agreements, instruments,
                  documents, certificates, and opinions as the Agent may
                  reasonably request.


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         If this Amendment becomes effective, the changes in the Domestic Rate
Margin and Eurocurrency Margin shall take effect with respect to any Loans and
Letters of Credit outstanding on May 1, 2000 and on each day thereafter, but any
payment of interest or fees due on or after May 1, 2000 with respect to Loans or
Letters of Credit outstanding prior thereto shall be computed on the basis of
the Domestic Rate Margin or Eurocurrency Margin, as applicable, in effect prior
to such effectiveness.

         This Amendment may be executed in any number of counterparts and by
different parties hereto on separate counterpart signature pages, each of which
when so executed shall be an original but all of which shall constitute one and
the same instrument. Except as specifically amended and modified hereby, all of
the terms and conditions of the Credit Agreement and the other Credit Documents
shall remain unchanged and in full force and effect. All references to the
Credit Agreement in any document shall be deemed to be references to the Credit
Agreement as amended hereby. All capitalized terms used herein without
definition shall have the same meaning herein as they have in the Credit
Agreement. This Amendment shall be construed and governed by and in accordance
with the internal laws of the State of Illinois.


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         Dated as of the date first above written.

                            ATCHISON CASTING CORPORATION

                            By: /s/ Kevin T. McDermed
                                -----------------------------------------------
                            Title: V.P. & Treasurer
                                   --------------------------------------------

                            HARRIS TRUST AND SAVINGS BANK, in its individual
                               capacity as a Bank and as Agent

                            By: /s/ Len E. Meyer
                                -----------------------------------------------
                            Title: Vice President
                                   --------------------------------------------

                            COMMERCE BANK, N.A.

                            By: /s/ Dennis R. Block
                                -----------------------------------------------
                            Title: Senior Vice President
                                   --------------------------------------------

                            FIRSTAR BANK MIDWEST (f/k/a Mercantile Bank)

                            By: /s/ Barry P. Sullivan
                                -----------------------------------------------
                            Title:  Vice President
                                    -------------------------------------------

                            KEY BANK NATIONAL ASSOCIATION

                            By: /s/ Daniel M. Lally
                                -----------------------------------------------
                            Title:  Assistant Vice President
                                    -------------------------------------------


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                            COMERICA BANK

                            By: /s/ Jeffrey E. Peck
                                -----------------------------------------------
                            Title: Vice President
                                   --------------------------------------------

                            HIBERNIA NATIONAL BANK

                            By: /s/ Angela Bomttey
                                -----------------------------------------------
                            Title: Vice President
                                   --------------------------------------------

                            NATIONAL WESTMINSTER BANK PLC

                            Nassau Branch

                            By: /s/ P. Mills
                                -----------------------------------------------
                            Title: Senior Corporate Manager
                                   --------------------------------------------

                            New York Branch

                            By: /s/ P. Mills
                                -----------------------------------------------
                            Title: Senior Corporate Manager
                                   --------------------------------------------

                            WELLS FARGO BANK, NATIONAL ASSOCIATION
                               (successor by merger to Norwest Bank
                               Minnesota, N.A.)

                            By: /s/ R. Duncan Sinclair
                                -----------------------------------------------
                            Title: Vice President
                                   --------------------------------------------