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                                   EXHIBIT 4.1


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                 FIFTH AMENDMENT TO THE NOTE PURCHASE AGREEMENT

                  This Fifth Amendment to the Note Purchase Agreement (this
"Fifth Amendment") dated as of December 21, 1999 between ATCHISON CASTING
CORPORATION (the "Company") and TEACHERS INSURANCE AND ANNUITY ASSOCIATION OF
AMERICA (the "Holder");

                              W I T N E S S E T H:

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a Note Purchase Agreement dated as of July 29, 1994 (as amended by
the First Amendment, the Second Amendment, the Third Amendment, the Letter
Agreement and the Fourth Amendment described below, the "Note Purchase
Agreement") pursuant to which the Holder purchased $20,000,000 in aggregate
principal amount of the Company's 8.44% Senior Notes due July 29, 2004 (the
"Notes"); and

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a First Amendment to the Note Purchase Agreement dated as of March
8, 1996 (the "First Amendment"); and

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a Second Amendment to the Note Purchase Agreement dated as of May
24, 1996 (the "Second Amendment"); and

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a Third Amendment to the Note Purchase Agreement dated as of April
3, 1998 (the "Third Amendment"); and

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a Letter Agreement to the Note Purchase Agreement dated as of
October 12, 1998 (the "Letter Agreement"); and

                  WHEREAS, the Company and the Holder have heretofore executed
and delivered a Fourth Amendment to the Note Purchase Agreement dated as of
October 20, 1999 (the "Fourth Amendment"); and

                  WHEREAS, the parties hereto desire to further amend the Note
Purchase Agreement to enable the Company to issue up to $35,000,000 of Debt to
General Electric Capital Corporation or its assignees ("GE Capital Corporation")
pursuant to documentation acceptable to the Holder (the "GE Financing") and to
make certain other amendments to the Note Purchase Agreement as provided herein;


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

         A.       1.  SECTION 6.1 of the Note Purchase Agreement is hereby
amended : (i) by deleting subsection (c) in its entirety and substituting in
lieu thereof:

                  "RATIO OF CONSOLIDATED TOTAL DEBT TO TOTAL CAPITALIZATION. The
Company will not on any date permit Consolidated Total Debt to exceed 55% of
Total Capitalization."

 (ii) by deleting subsection (d) in its entirety; and

 (iii) by deleting subsection (e) in its entirety and replacing in lieu thereof:

                  "FIXED CHARGE COVERAGE RATIO. The Company will not, as of the
last day of any fiscal quarter of the Company, permit the Fixed Charge Coverage
Ratio:

                  (i) for the period from and including December 31, 1999 to and
         including March 30, 2000, to be less than 1.10;

                  (ii) for the period from and including March 31, 2000 to and
         including March 30, 2001, to be less than 1.25; and

                  (iii) for the period from and including March 31, 2001 and
         thereafter, to be less than 1.50."



                  2. SECTION 6.4 of the Note Purchase Agreement is hereby
amended by: (i) (x)deleting the word "and" at the end of subsection (g); (y)
replacing the "." at the end of subsection (h)(iv) with "; and"; and (z)
inserting after subsection (h) the following subsection (i):

                  (i) Liens upon certain assets and real estate of the Company
         as approved by the Holder located in Atchison, Kansas and St. Joseph,
         Missouri securing the GE Financing.

         and (ii) by replacing the "(h)" in the third line of the last paragraph
         with "(i)".

                  3. The definition of "FIXED CHARGES" appearing in SECTION 9.1
of the Note Purchase Agreement is hereby amended in its entirety and as so
amended shall read as follows:


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                  "FIXED CHARGES: as applied to any Person for any period, the
sum of (a) Interest Expense of such Person for such period, PLUS (b) the
aggregate amount of Current Maturities, PLUS (c) 15% of the aggregate principal
amount of revolving loans issued pursuant to the Credit Agreement outstanding on
the last day of such period; PROVIDED that if the Company obtains a commitment
from GE Capital Corporation in form and substance acceptable to the Holder by no
later than December 22, 1999 to extend to the Company the GE Financing on or
prior to January 31, 2000, clause (c) shall only be effective from and after
July 1, 2000; PROVIDED FURTHER that if GE Capital Corporation does not advance
the GE Financing on or prior to January 31, 2000, clause (c) above shall be
effective for all calculations at all times after October 1, 1999. "

         B. The Company hereby represents and warrants to the Holder that the
representations and warranties with respect to the Company contained in the Note
Purchase Agreement as updated hereby by Schedules 7.19, II, III, IV, V and VI
attached hereto are true and correct in all material respects and the Holder
shall be entitled to rely on such representations and warranties as if they were
made to the Holder in this Amendment as of the date hereof.

         C. This Fifth Amendment shall become effective upon execution and
delivery of this Fifth Amendment.

         This Fifth Amendment may be executed in any number of counterparts and
by each party 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 Note Purchase Agreement shall remain unchanged and
in full force and effect. All references to the Note Purchase Agreement in any
document shall be deemed to be references to the Note Purchase Agreement as
amended hereby. All capitalized terms used herein without definition shall have
the same meaning herein as they have in the Note Purchase Agreement.


         This Fifth Amendment shall be construed and governed by and in
accordance with the laws of the State of New York.

                  Dated as of the date first above written.


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                            ATCHISON CASTING CORPORATION



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



                            TEACHERS INSURANCE AND ANNUITY
                                ASSOCIATION OF AMERICA



                            By /s/ Loren S. Archibald
                              ---------------------------------
                              Name: Loren S. Archibald
                              Title: Managing Director Private Placements


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