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                                                               Exhibit 10.14

                    SECOND AMENDMENT TO CREDIT AGREEMENT
                    ------------------------------------

         This Second Amendment to Credit Agreement (this "Amendment") is
made and entered into as of the 13th day of January, 2004, by and among
ZOLTEK COMPANIES, INC., a Missouri corporation having its chief executive
office and principal place of business located at 3101 McKelvey Road, St.
Louis, Missouri 63044 ("Parent"), ZOLTEK CORPORATION, a Missouri
corporation, CAPE COMPOSITES, INC., a California corporation, ENGINEERING
TECHNOLOGY CORPORATION, a Missouri corporation, and ZOLTEK PROPERTIES, INC.,
a Missouri corporation, (individually and collectively hereinafter
"Borrowers"; all references to "Borrowers" or "Borrower" shall mean each and
all of the Borrowers) and SOUTHWEST BANK OF ST. LOUIS (the "Bank"), with an
office at 13205 Manchester Road, St. Louis, Missouri 63131.

                            W I T N E S S E T H:

         WHEREAS, Bank and Borrowers are parties to that certain Credit
Agreement dated as of May 11, 2001, as amended by that certain First
Amendment to Credit Agreement dated as of February 13, 2003 (as amended, the
"Agreement"); and

         WHEREAS, Bank and Borrowers desire to amend the Agreement upon and
subject to the terms and conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the premises, the covenants,
promises and agreements hereinafter set forth, and other good and valuable
consideration, the receipt and sufficiency of which hereby is acknowledged,
the parties hereto agree as follows:

         1. Amendments to the Agreement.
            ---------------------------

                  (a) Section 3.02 of the Agreement is hereby deleted in its
                      ------------
         entirety and replaced by the following:

                           3.02 TERM OF REVOLVING CREDIT FACILITY. Subject
                                ---------------------------------
                  to the Bank's right to cease making Loans to the Borrowers
                  at any time upon or after the occurrence and during the
                  continuation of any Default or Event of Default, the
                  Borrowers shall be entitled to request advances under the
                  Revolving Credit Note for the period from the date hereof
                  to and including January 31, 2005. In no event may the
                  Borrowers terminate this Agreement until the Borrowers
                  have repaid all Loans and otherwise paid and performed
                  their Obligations hereunder. All indemnities given by the
                  Borrowers to the Bank under any of the Loan Documents
                  shall survive the repayment of the Loans and the
                  termination of this Agreement.

                  (b) Section 3.03(a) of the Agreement is hereby deleted in
                      ---------------
         its entirety and replaced by the following:

                                    (a) Principal payable on account of the
                           Revolving Credit Loan shall be payable by the
                           Borrowers to the Bank immediately upon the
                           earliest to occur of (i) the date or dates for
                           payment as specified in the Revolving Credit
                           Note, (ii) the occurrence of any event described
                           in Section 3.04 hereof which requires the payment
                              ------------
                           of principal on the Loans (but only after the
                           Term Loan has been repaid in full), (iii) the
                           occurrence and continuance of an Event of Default
                           in consequence of which the Bank elects to
                           accelerate the maturity and payment of


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                           any of the Obligations, (iv) termination of this
                           Agreement for any reason, or (v) January 31, 2005
                           (the "Revolving Loan Maturity Date"); provided,
                           however, that if the principal balance of
                           Revolving Credit Loan outstanding at any time
                           shall exceed the Borrowing Base at such time, the
                           Borrowers shall, on demand, repay the Revolving
                           Credit Loan in an amount sufficient to reduce the
                           aggregate unpaid principal amount of such
                           Revolving Credit Loans by an amount equal to such
                           excess;

         2. Conditions To Execution Of This Amendment. Any provision
            -----------------------------------------
contained herein or in the Agreement to the contrary notwithstanding, Bank's
execution of this Amendment is subject to the following:

                  (a) Bank shall have first received a certified copy of the
         resolutions of each Borrower, duly adopted and authorizing the
         execution, delivery and performance of this Amendment in accordance
         with its terms;

                  (b) All representations and warranties made in the
         Agreement and herein shall be true and correct in all material
         respects as of the date hereof and, by execution of this Amendment,
         each Borrower hereby certifies same to Bank;

                  (c) After giving effect to this Amendment, no Borrower
         shall have defaulted, or taken or failed to take any action which,
         unless corrected, would give rise to a default on any of its
         obligations to Bank;

                  (d) After giving effect to this Amendment, no action or
         omission exists as of the date hereof which constitutes, or which,
         with the passage of time, would constitute a Default or Event of
         Default, and each Borrower shall have certified the same to Bank by
         a duly authorized officer;

                  (e) Each Borrower shall be in compliance with all
         covenants of the Agreement, as amended;

                  (f) All documents and filings necessary to maintain and
         perfect Bank's security interest in the collateral provided for in
         the Loan Documents shall be in full force and effect, and all
         actions necessary to maintain and perfect the same shall have
         been taken;

                  (g) No material adverse change in the financial condition
         of the Borrowers taken as a whole shall have occurred since June
         30, 2003;

                  (h) Bank shall have received the following documents, duly
         executed and delivered by all parties thereto, and otherwise
         reasonably satisfactory in form and content to Bank and its
         counsel:

                           (i)      An Amended and Restated Revolving Credit
                                    Note in the form of Exhibit A attached
                                                        ---------
                                    hereto (which shall also serve as the
                                    revised Exhibit A of the Agreement);
                                            ---------

                           (ii)     A photocopy of a fully executed original
                                    of the Securities Purchase Agreement
                                    dated as of December 19, 2003 (as same
                                    may have been amended, the "Securities
                                    Purchase Agreement") by and among Parent
                                    and the Investors (as defined therein);
                                    and

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                           (iii)    A good standing certificate from the
                                    Secretary of State for the
                                    organizational State of each Borrower.

                  (i) The following events shall have occurred or shall
         occur contemporaneously with the closing of the transactions
         contemplated herein:

                           (i)      In addition to, and not in lieu of, any
                                    regularly scheduled principal payments
                                    on same, Bank shall have received a
                                    principal payment of not less than
                                    $2,000,000.00 with respect to that
                                    certain Amended and Restated Term Loan
                                    Note dated as of February 13, 2003 in
                                    the original principal amount of
                                    $3,500,000.00;

                           (ii)     Any and all indebtedness due Bank under
                                    that certain Promissory Note dated
                                    August 12, 1997 in the original
                                    principal amount of $2,407,345.19 and
                                    executed by Zoltek Properties, Inc. in
                                    favor of Bank shall have been paid in
                                    full;

                           (iii)    Any and all amounts due Bank or
                                    otherwise remaining to be paid to Bank
                                    under that certain Master Equipment
                                    Lease dated as of January 1, 1999 (as
                                    same may have been amended, the "Abilene
                                    Lease") by and between the Borrowers and
                                    Bank shall be paid in full. As of
                                    January 9, 2004, the amount to be paid
                                    to Bank to complete or otherwise fulfill
                                    the Borrowers' lease payment obligations
                                    under the Abilene Lease is
                                    $1,839,137.66, with per diem interest in
                                    the amount of $272.85.

                           (iv)     Bank shall have received evidence
                                    satisfactory to Bank that Parent has
                                    received (i) an amount not less than
                                    $7,000,000.00 in connection with the
                                    sale of the Debentures described in the
                                    Securities Purchase Agreement, and (ii)
                                                                   ---
                                    advanced funds in a principal amount not
                                    less than $5,000,000.00 under a credit
                                    facility between the Borrowers and Beal
                                    Bank; and

                           (v)      Bank shall have received evidence
                                    satisfactory to the Bank that Parent has
                                    repaid the borrowings by Parent from
                                    Zsolt Rumy in the amount of
                                    $1,400,000.00 and secured the release of
                                    the letter of credit posted by Zsolt
                                    Rumy for the benefit of Parent in the
                                    amount of $1,400,000.00.

                  (j) No pending or threatened litigation or other
         proceeding or investigation shall exist which could reasonably be
         expected to have a material adverse effect on the prospects,
         operation or financial condition of the Borrowers taken as a whole;
         and

                  (k) The Borrowers shall pay the costs and expenses of Bank
         (including reasonable attorneys' fees and expenses) in connection
         with the negotiation, preparation, execution and delivery of this
         Amendment and all other matters herein provided for or required in
         connection with this Amendment.

         3. Bank Waivers and Consents. Bank agrees to the following waivers
            -------------------------
and consents:

                  (a) Bank hereby waives compliance with the financial
         covenants contained in Section 6.03(a) (Minimum Working Capital),
                                ---------------
         Section 6.03(b) (Debt Coverage Ratio), and Section 6.03(c) (Current
         ---------------                            ---------------
         Ratio) of the Agreement. Such waiver shall be effective from and
         including September


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<PAGE>

         30, 2003 through all covenant testing dates prior to March 31,
         2005. The Borrowers shall be in compliance with such financial
         covenants when tested on March 31, 2005.

                  (b) Notwithstanding any prohibitions contained in the
         Agreement to the contrary, Bank hereby consents to, and waives any
         Default or Event of Default caused by, the following actions taken,
         or to be taken, by the Borrowers:

                           (i)      The sale and issuance of the Debentures
                                    described in the Securities Purchase
                                    Agreement;

                           (ii)     The establishment of, and borrowing
                                    under, a credit facility with Beal Bank
                                    in the approximate principal amount of
                                    $6,000,000.00 and the accompanying liens
                                    granted to Beal Bank with respect to (i)
                                    the real property (including the
                                    improvements and fixtures thereon) of
                                    Borrowers' located at 3101 McKelvey
                                    Road, St. Louis, Missouri, 11 Missouri
                                    Research Park, St. Charles, Missouri and
                                    1221 Fulwiler Road, Abilene, Texas, and
                                    (ii) the personal property which is the
                                    subject of the Abilene Lease; and

                           (iii)    The borrowing of funds by Parent in the
                                    aggregate amount of $2,800,000.00 from
                                    Zsolt Rumy, which borrowings are in the
                                    form of cash borrowings in the amount of
                                    $1,400,000.00 and a standby letter of
                                    credit in the amount of $1,400,000.00
                                    posted for the Parent's benefit.

         4. Representations and Warranties. The Borrowers hereby represent
            ------------------------------
and warrant to Bank that:

                  (a) All representations and warranties made by the
         Borrowers in the Agreement are true and correct in all material
         respects as if they had been made on the date hereof.

                  (b) No Default or Event of Default exists within the
         meaning of the Agreement.

                  (c) The officers of the Borrowers executing this Amendment
         shall be fully authorized to do so, and all corporate actions
         necessary or proper to authorize the execution of this Amendment
         have been duly done, taken and performed. No consent, authorization
         or approval of any other Person is necessary for the due execution
         and delivery by any Borrower of this Amendment and the performance
         by any Borrower of the terms hereof and thereof. This Amendment is
         executed and delivered in accordance with any laws and regulations
         applicable hereto and thereto, and is the legal, valid and binding
         obligation of each Borrower, enforceable in accordance with its
         terms.

                  (d) The execution, delivery, and performance, in
         accordance with its terms, of this Amendment will not violate any
         provision of any Borrower's organizational documents, any law, or
         any applicable judgment or regulation of any court or of any public
         or governmental agency, officer, or authority, and will not
         conflict with, result in a breach of or default under, or result in
         the creation of any lien, charge or encumbrance upon any of the
         property or assets of any Borrower (except for the security
         interest created by the Loan Documents) under any indenture,
         mortgage, contract, deed of trust, or other agreement to which any
         Borrower is a party or by which any Borrower or any of its
         properties or assets is or may be bound.

         5. Entire Agreement. This Amendment and the Agreement embody the
            ----------------
entire agreement between the parties respecting the subject matter hereof
and supersede all prior agreements, proposals,


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<PAGE>

communications and understandings relating to such subject matter. The terms
of the Amendment shall be considered a part of the Agreement as if fully set
forth therein.

         6. Miscellaneous. This Amendment shall be binding upon the
            -------------
Borrowers and their respective successors and the Bank and its successors
and assigns. The Section headings are furnished for the convenience of the
parties and are not to be considered in the construction or interpretation
of this Amendment or the Agreement. This Amendment may be executed in any
number of counterparts, each of which shall be deemed an original, but which
together shall constitute one and the same instrument. Capitalized terms not
defined herein shall have the meanings set forth in the Agreement. This
Agreement shall be a contract made under and governed by the laws of the
State of Missouri applicable to contracts made and to be performed entirely
within such State.

         7. No Other Amendments. In case of a conflict between the terms of
            -------------------
this Amendment and the Agreement, the terms of this Amendment control.
Except as expressly set forth in this Amendment, the terms of the Agreement
remain unchanged and in full force and effect. The following notice is given
pursuant to Section 432.045 of the Missouri Revised Statutes; nothing
contained in such notice shall be deemed to limit or modify the terms of the
Loan Documents:

ORAL AGREEMENTS OR COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO FORBEAR
FROM ENFORCING REPAYMENT OF A DEBT INCLUDING PROMISES TO EXTEND OR RENEW
SUCH DEBT ARE NOT ENFORCEABLE. TO PROTECT YOU (BORROWERS) AND US (BANK) FROM
MISUNDERSTANDING OR DISAPPOINTMENT, ANY AGREEMENTS WE REACH COVERING SUCH
MATTERS ARE CONTAINED IN THIS WRITING, WHICH IS THE COMPLETE AND EXCLUSIVE
STATEMENT OF THE AGREEMENT BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN
WRITING TO MODIFY IT.

                          [SIGNATURE PAGE FOLLOWS]



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IN WITNESS WHEREOF, the parties have executed this Amendment as of the day
and year first above written.

                                  BORROWERS:

                                  ZOLTEK COMPANIES, INC.

                                  By: /s/ Zsolt Rumy
                                     -----------------------------------------
                                  Name: Zsolt Rumy
                                       ---------------------------------------
                                  Title: President
                                        --------------------------------------


                                  ZOLTEK CORPORATION

                                  By: /s/ Zsolt Rumy
                                     -----------------------------------------
                                  Name: Zsolt Rumy
                                       ---------------------------------------
                                  Title: President
                                        --------------------------------------


                                  CAPE COMPOSITES, INC.

                                  By: /s/ Zsolt Rumy
                                     -----------------------------------------
                                  Name: Zsolt Rumy
                                       ---------------------------------------
                                  Title: President
                                        --------------------------------------


                                  ENGINEERING TECHNOLOGY CORPORATION

                                  By: /s/ Zsolt Rumy
                                     -----------------------------------------
                                  Name: Zsolt Rumy
                                       ---------------------------------------
                                  Title: President
                                        --------------------------------------


                                  ZOLTEK PROPERTIES, INC.

                                  By: /s/ Zsolt Rumy
                                     -----------------------------------------
                                  Name: Zsolt Rumy
                                       ---------------------------------------
                                  Title: President
                                        --------------------------------------




                                  BANK:

                                  SOUTHWEST BANK OF ST. LOUIS

                                  By: /s/ John D. Haffemkeffer
                                     -----------------------------------------
                                  Name: John D. Haffemkeffer
                                       ---------------------------------------
                                  Title: EVP
                                        --------------------------------------



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                                  EXHIBIT A
                                  ---------

                 AMENDED AND RESTATED REVOLVING CREDIT NOTE
                 ------------------------------------------


US $5,000,000.00                                            January 13, 2004
                                                         St. Louis, Missouri

         For value received, the undersigned, Zoltek Companies, Inc., a
Missouri corporation, Zoltek Corporation, a Missouri corporation, Zoltek
Properties, Inc., a Missouri corporation, Engineering Technology
Corporation, a Missouri corporation and Cape Composites, Inc., a California
corporation (individually and collectively hereinafter "Borrowers"; all
references to "Borrowers" or "Borrower" shall mean each and all of the
Borrowers), hereby jointly and severally promise to pay to the order of
Southwest Bank of St. Louis (the "Bank"), in lawful money of the United
States of America, the principal sum of Five Million Dollars
($5,000,000.00), or if less, the amount outstanding under Section 2.02 of
                                                          ------------
the Credit Agreement (as hereinafter defined), together with interest from
the date hereof at the rate provided for in the Credit Agreement. Principal
and interest of this Note shall be payable at the time or times provided in
Section 3 of the Credit Agreement.
---------

         This Amended and Restated Revolving Credit Note (this "Note") is
the Revolving Credit Note referred to in, and is issued pursuant to, that
certain Credit Agreement among the Borrowers, Hardcore Composites
Operations, LLC and the Bank dated as of May 11, 2001, as amended by that
certain First Amendment to Credit Agreement dated as of February 13, 2003,
and that certain Second Amendment to Credit Agreement of even date herewith
(as further amended or otherwise modified from time to time, the "Credit
Agreement"), and is entitled to all of the benefits and security of the
Credit Agreement. All of the terms, covenants and conditions of the Credit
Agreement and all other instruments evidencing or securing the indebtedness
hereunder are hereby made a part of this Note and are deemed incorporated
herein in full. All capitalized terms used herein, unless otherwise
specifically defined in this Note, shall have the meanings ascribed to them
in the Credit Agreement.

         This Note is secured by the Collateral described in the Credit
Agreement.

         Interest hereunder shall be computed on, the basis of actual days
elapsed over the period of a 360-day year. Upon or after the occurrence and
during the continuation of any Event of Default, the outstanding principal
balance of this Note shall bear interest at a variable rate per annum equal
to the Default Rate until the principal balance of this Note is paid in
full.

         In no contingency or event whatsoever, whether by reason of
advancement of the proceeds hereof or otherwise, shall the amount paid or
agreed to be paid to the Bank for the use, forbearance or detention of money
advanced hereunder exceed the highest lawful rate permissible under any law
which a court of competent jurisdiction may deem applicable hereto.

         The Borrowers may prepay this Note, in whole or in part, at any
time without premium or penalty.

         The termination of the Credit Agreement or the occurrence and
continuance of an Event of Default shall entitle the Bank, at its option, to
declare the then outstanding principal balance and accrued interest hereon
to be, and the same shall thereupon become, immediately due and payable
without notice to or demand upon the Borrowers, all of which the Borrowers
hereby expressly waive.


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<PAGE>

         Time is of the essence of this Note. To the fullest extent
permitted by applicable law, the Borrowers, for themselves and their
successors and assigns, expressly waive presentment, demand, protest and
notice of dishonor, and hereby consent to any extensions of time, renewals,
release of any parties to or guarantors of this Note, waivers and any other
modifications that may be granted or consented to by the Bank from time to
time in respect of the time of payment or any other provision of this Note.

         Wherever possible each provision of this Note shall be interpreted
in such a manner as to be effective and valid under applicable law, but if
any provision of this Note shall be prohibited or invalid under applicable
law, such provision shall be ineffective to the extent of such prohibition
or invalidity without invalidating the remainder of such provision or
remaining provisions of this Note. No delay or failure on the part of the
Bank in the exercise of any right or remedy hereunder shall operate as a
waiver thereof, nor as an acquiescence in any default, nor shall any single
or partial exercise by the Bank of any right or remedy preclude any other
right, or remedy. The Bank, at its option, may enforce its rights against
any collateral securing this Note without enforcing its rights against the
Borrowers, any guarantor of the indebtedness evidenced hereby or any other
property or indebtedness due or to become due to the Borrowers. The
Borrowers agree that, without releasing or impairing the Borrowers'
liability hereunder, the Bank may at any time release, surrender, substitute
or exchange any collateral securing this Note and may at any time release
any party primarily or secondarily liable for the indebtedness evidenced by
this Note.

         This Note is a restated and amended version of that certain Amended
and Restated Revolving Credit Note dated as of February 13, 2003, executed
by Borrowers in favor of Bank in the original principal amount of
$5,000,000.00, and shall not constitute a cancellation of the principal
amount of such note evidenced thereby.

         This Note shall be governed by, and construed and enforced in
accordance with, the internal laws of the State of Missouri.

         BORROWERS HEREBY WAIVE ANY RIGHT TO TRIAL BY JURY (WHICH BANK ALSO
WAIVES) IN ANY ACTION, SUITE, PROCEEDING OR COUNTERCLAIM OF ANY KIND ARISING
OUT OF OR RELATING TO THIS NOTE OR ANY OF THE LOAN DOCUMENTS, THE
COLLATERAL, OR BANK'S CONDUCT IN RESPECT OF ANY OF THE FOREGOING.

         IN WITNESS WHEREOF, the Borrowers have caused this Note to be
executed and delivered by their respective duly authorized representatives
as of the date first above written.

                                  ZOLTEK COMPANIES, INC.

                                  By:
                                     -----------------------------------------
                                  Name:
                                       ---------------------------------------
                                  Title:
                                        --------------------------------------


                                  ZOLTEK CORPORATION

                                  By:
                                     -----------------------------------------
                                  Name:
                                       ---------------------------------------
                                  Title:
                                        --------------------------------------

                                     2

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                                  ZOLTEK PROPERTIES, INC.

                                  By:
                                     -----------------------------------------
                                  Name:
                                       ---------------------------------------
                                  Title:
                                        --------------------------------------


                                  ENGINEERING TECHNOLOGY CORPORATION

                                  By:
                                     -----------------------------------------
                                  Name:
                                       ---------------------------------------
                                  Title:
                                        --------------------------------------


                                  CAPE COMPOSITES, INC.

                                  By:
                                     -----------------------------------------
                                  Name:
                                       ---------------------------------------
                                  Title:
                                        --------------------------------------


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