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                                                                    EXHIBIT 10.4

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                                     FOURTH
                           AGREEMENT FOR EXTENSION OF
                                 EXPIRATION DATE
                               PEGOS MACHINE CORP.

This FOURTH Agreement for Extension of Expiration Date ("Agreement") dated as of
August 11, 2000, by and among FLEET NATIONAL BANK, a national banking
association with a place of business at 777 Main Street, Hartford, CT, 06115
("Lender"), PEGOS MACHINE CORP., a Connecticut Corporation with an address at
145 Hyde Road, Farmington ("Borrower"), EDAC TECHNOLOGIES CORPORATION, a
Wisconsin corporation with a place of business at 1806 New Britain Ave.,
Farmington, CT 06032 ("EDAC"), and MICHAEL ALOS ("Alos")(EDAC and Alos
hereinafter collectively "Guarantor").

                                    RECITALS

On or about August 20, 1997, the Borrower and the Lender entered into a Line of
Credit Agreement (the "Line of Credit Agreement"), which evidenced a line of
credit for the Borrower's short term borrowing needs (the "Loan") with a credit
limit as described therein.

On or about August 20, 1997, and pursuant to the Line of Credit Agreement, the
Borrower executed and delivered to the Lender its Line of Credit Promissory Note
(the "Note"), in the maximum principal amount of $300,000.

In connection with the Line of Credit Agreement and the Note, the Guarantor
executed and delivered to the Lender its unconditional guaranty of payment of
the obligations of the Borrower, (the "Guaranty"), which Guaranty is dated
August 20, 1997.

In furtherance of its Guaranty, and as an inducement to the Lender to enter into
the Line of Credit Agreement and the Note, the EDAC executed and delivered to
the Lender its Subordination Agreement dated August 20, 1997 (the "Subordination
Agreement"), by virtue of which the EDAC agreed that any and all obligations
owed to it by the Borrower were fully subordinated and payment thereof was
deferred until the full and final payment in cash of all obligations owed to the
Lender.

The Line of Credit Agreement provides, among other things, that all sums due
under the Note and the Line of Credit Agreement would be due and payable in full
on March 31, 2000.

By virtue of the parties several prior Agreement[s] for Extension of Expiration
Date - Pegos Machine Corp., the due and payable date of March 31, 2000 was
extended to August 18, 2000.

The Borrower and the Guarantor have requested that the Lender agree to further
extend the maturity date for the Borrower's obligations owed under the Line of
Credit Agreement and the Note until August 25, 2000.


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NOW THEREFORE, in consideration of the premises and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
Lender, Borrower and Guarantor here by agree, represent and warrant as follows:

         1. The Borrower and Guarantor acknowledge that they are unconditionally
indebted to the Lender in accordance with their respective Note and Guaranty in
the amount of not less than $300,000, plus all interest, costs, fees and
expenses (the "Indebtedness") as provided therein. The Borrower and Guarantor
acknowledge that they have no valid defense, set-off or counterclaim to their
obligations in respect of the Indebtedness, and further that they have no other
claim whatsoever against the Lender (whether arising in contract, tort or
otherwise) with respect to the Indebtedness or for any other matter.

         2. The Borrower and Guarantor admit the validity, due execution and
enforceability of the Note, the Line of Credit Agreement and the Guaranty.

         3. The Lender agrees to the request of the Borrower and the Guarantor
that the maturity of the Line of Credit Agreement and the Note is and shall be
extended to August 25, 2000. The Line of Credit Agreement and the Note shall
remain the same in all other terms and respects, enforceable in accordance with
their terms.

         4. The Guarantor reaffirms its Guaranty in all respects, and
specifically agrees, stipulates and acknowledges that it remains fully liable on
the Indebtedness in accordance with the terms of the Guaranty, notwithstanding
this extension of the maturity date, and EDAC further reaffirms and restates as
of this date its Subordination Agreement.

         5. The Borrower and Guarantor represent and warrant to the Lender that
they have the requisite corporate power to enter into this Agreement and the
transactions contemplated herein, and that they have taken all necessary
corporate action to authorize this Agreement and the transactions contemplated
herein.

         6. As a further inducement to Lender to enter into this Agreement and
to grant the accommodations contained herein, effective on the date hereof, the
Borrower and Guarantor do hereby release, acquit and forever discharge Lender,
its respective representatives, parents, subsidiaries, affiliates, officers,
directors, agents, employees, servants, attorneys and representatives, as well
as the respective personal representatives, successors and assigns of any and
all of them (collectively, the "Released Lender Parties"), from and against any
and all claims (including without limitation, any so-called "lender liability"
claims or defenses), demands, debts, actions, causes of action, suits,
contracts, agreements, obligations, accounts, defenses, offsets against any of
the Indebtedness, and liabilities of any kind or character whatsoever, known or
unknown, suspected or unsuspected, in contract or in tort at law or in equity,
including without implied limitation, such claims and defenses as fraud,
mistake, failure of consideration and duress, which the Borrower, the Guarantor
and/or anyone claiming by or through any of them ever had, now has, or might
hereafter have against any of the Released Lender Parties for or by reason of
any matter, cause or thing whatsoever occurring from the beginning of time
through and including the date hereof which relates to, in whole or in part
directly or indirectly the Line of Credit Agreement, the Guaranty and the Note
or the administration of any of the



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Indebtedness or conduct of Lender or of any of the other Released Lender
Parties. In addition, the Borrower and each Guarantor agrees not to commence,
join in, assist, prosecute or participate in any suit or other proceeding
against any of the Released Lender Parties relating directly or indirectly to
any of the foregoing matters or otherwise contrary to the provisions set forth
above.

         7. LENDER, BORROWER AND GUARANTOR EXPRESSLY WAIVE TRIAL BY JURY IN ANY
COURT AND IN ANY SUIT, ACTION OR PROCEEDING ON ANY MATTER ARISING IN CONNECTION
WITH OR IN ANY WAY RELATED TO THE FINANCING TRANSACTIONS OF WHICH THE LOAN AND
FORBEARANCE DOCUMENTS ARE A PART AND/OR THE ENFORCEMENT OF ANY OF LENDER'S
RIGHTS AND REMEDIES THEREUNDER, INCLUDING WITHOUT LIMITATION, TORT CLAIMS.

         8. BORROWER AND GUARANTOR ACKNOWLEDGE THAT THE TRANSACTIONS EVIDENCED
BY THE LINE OF CREDIT AGREEMENT, THE NOTE, THE GUARANTY AND THIS AGREEMENT ARE
COMMERCIAL TRANSACTIONS AND WAIVE THEIR RESPECTIVE RIGHTS TO NOTICE AND HEARING
UNDER CHAPTER 903a OF THE CONNECTICUT GENERAL STATUES, OR AS OTHERWISE ALLOWED
BY THE LAW OF ANY STATE OR FEDERAL LAW WITH RESPECT TO ANY PREJUDGMENT REMEDY
WHICH LENDER MAY DESIRE TO USE, AND FURTHER WAIVE THEIR RESPECTIVE RIGHT TO
REQUEST THAT LENDER POST A BOND, WITH OR WITHOUT SURETY, TO PROTECT BORROWER
AND/OR GUARANTOR AGAINST DAMAGES THAT MAY BE CAUSED BY ANY PREJUDGMENT REMEDY
SOUGHT OR OBTAINED BY LENDER BY VIRTUE OF ANY DEFAULT OR PROVISION OF THIS
AGREEMENT OR ANY OF THE OTHER LOAN AND FORBEARANCE DOCUMENTS.

         9. THE BORROWER AND GUARANTOR ACKNOWLEDGE THAT THEY MAKE THE WAIVERS
SET FORTH HEREIN KNOWINGLY, VOLUNTARILY AND WITHOUT DURESS AND ONLY AFTER
EXTENSIVE CONSIDERATION OF THE RAMIFICATIONS OF THOSE WAIVERS WITH THEIR
ATTORNEYS. EACH OF BORROWER AND GUARANTOR FURTHER ACKNOWLEDGE THAT LENDER HAS
NOT AGREED WITH OR REPRESENTED TO BORROWER, GUARANTOR OR ANY OTHER PARTY HERETO
THAT THE PROVISIONS HEREIN WILL NOT BE FULLY ENFORCED IN ALL INSTANCES.

         10. Borrower and Guarantor shall from time to time execute and deliver
such additional documents and take such additional actions and shall provide
such additional information as Lender may reasonably require to carry out the
terms and conditions of this Agreement.

         11. This Agreement and the Line of Credit Agreement, the Note and the
Guaranty and all transactions, assignments and transfers hereunder and
thereunder, and all rights of the parties, shall be governed as to validity,
construction enforcement and in all other respects by the laws of the State of
Connecticut (but not its conflict of laws provisions).
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         12. This Agreement may be executed in any number of counterparts, each
of which shall constitute an original and all of which, when taken together,
shall constitute one instrument.

         13. This Agreement shall be binding upon each Borrower and Guarantor
and upon the respective heirs, successors, assigns and legal representatives of
each such Borrower and Guarantor, and shall inure to the benefit of Lender,
Lender's Affiliates and its successors, endorsees, and assigns. No right,
benefit, interest or obligation hereunder may be assigned by the Borrower or
Guarantor without the prior written consent of Lender. Lender may, in its sole
discretion and without notice to or consent of any Borrower or Guarantor, sell,
assign, grant a participation in or otherwise dispose of all or any portion of
its rights or interests in the Loan or the Loan Documents to any person or
entity, including, without limitation, any Borrower or Guarantor. In connection
therewith, Lender may disclose to a prospective purchaser, assignee, participant
or transferee, and their agents, attorneys or other consultants, any
information, confidential or otherwise, possessed by Lender relating to the Loan
Documents and the Loan and Forbearance Documents.


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In Witness Whereof, the parties have executed this Agreement as of the date
first written above.


                               LENDER:
                               Fleet National Bank

                               By: /s/G. Christopher Miller
                                   ------------------------
                                        G. Christopher Miller
                                        Its Vice President,
                                        (Duly Authorized)

                               BORROWER:
                               Pegos Machine Corporation

                               By: /s/Michael J. Alos
                                   ------------------

                                       Its
                                       (Duly Authorized)

                               GUARANTOR:
                               EDAC Technologies Corporation

                               By: /s/Ronald G. Popolizio
                                   ----------------------

                                       Its EVP and CFO
                                       (Duly Authorized)


                               /s/Michael J. Alos
                               ------------------
                               Michael Alos