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                                                                    EXHIBIT 10.1



                             SUPPLEMENTAL INDENTURE


         THIS SUPPLEMENTAL INDENTURE, dated as of October 15, 2004 (the
"Supplemental Indenture"), is made by and among Hawk Corporation, a Delaware
corporation (the "Company"), the guarantors named therein (the "Guarantors"),
and HSBC Bank USA, National Association (as successor to HSBC Bank USA), as
trustee under the Indenture referred to herein (the "Trustee").


                              W I T N E S S E T H:
                               - - - - - - - - - -

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an indenture, dated as of October 23, 2002 ( the "Indenture"), providing
for the issuance of an aggregate principal amount of up to $100.0 million of 12%
Senior Notes due 2006 (the "Notes");

         WHEREAS, the Company desires to amend certain provisions of the
Indenture as set forth herein, and it has received the consent of the holders of
a majority in principal amount of the Notes currently outstanding to such
amendments;

         WHEREAS, Section 9.2 of the Indenture permits the Indenture to be
amended by a supplemental indenture with the consent of the Holders of at least
a majority in principal amount of the Notes (including Additional Notes, if any)
outstanding voting as a single class, subject to certain enumerated exceptions;

         WHEREAS, the parties hereto are entering into this Supplemental
Indenture to amend or, as the case may be, delete certain provisions contained
in Sections 4, 5 and 10 of the Indenture (the "Amendments");

         WHEREAS, in addition, the Amendments will (i) delete certain "Events of
Default" and (ii) delete those definitions from the Indenture that are used only
in provisions that are eliminated as a result of the Amendments and revise
cross-references to provisions in the Indenture that have been deleted as a
result of the Amendments;

         WHEREAS, pursuant to Section 9.2 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture; and

         WHEREAS, all conditions set forth in the Indenture for the execution
and delivery of this Supplemental Indenture have been complied with;

         NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Company, the Guarantors and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

         SECTION 1. Capitalized Terms. Capitalized terms used herein without
definition shall have the respective meanings ascribed to them in the Indenture.

         SECTION 2. Amendments.

                  SECTION 2.1 Removal of Certain Provisions and Defined Terms.
The texts of Sections 4.3 through 4.5, 4.9 through 4.17, 5.2 and 10.9 of the
Indenture are hereby deleted in


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their entireties together with any references thereto in the Indenture and are
replaced in each case with the phrase "Intentionally Omitted." The definitions
of any and all terms that are defined in Section 1.01 but used only in one or
more of the Sections referenced in the immediately preceding sentence are
deleted in their entireties.

                  SECTION 2.2  Amendment of Section 5.1(a).

                  (a)      Section 5.1(a) of the Indenture ("Amended Section
5.1(a)") is hereby amended by deleting the language in Section 5.1(a) in its
entirety and replacing it with the following:

                  The Company shall not, in any single transaction or series of
         related transactions, consolidate or merge with or into (whether or not
         the Company is the Surviving Person), or sell, assign, transfer, lease,
         convey or otherwise dispose of all or substantially all of its
         properties or assets (determined on a consolidated basis for the
         Company and its Restricted Subsidiaries) in one or more related
         transactions to, another Person, and the Company will not permit any
         Restricted Subsidiary to enter into any such transaction or series of
         related transactions if such transaction or series of related
         transactions, in the aggregate, would result in a sale, assignment,
         transfer, lease, conveyance, or other disposition of all or
         substantially all of the properties and assets of the Company and the
         Restricted Subsidiaries, taken as a whole, to another Person, unless
         (i) the Surviving Person is a corporation organized or existing under
         the laws of the United States, any state thereof or the District of
         Columbia; and (ii) the Surviving Person (if other than the Company or a
         Guarantor) assumes all the obligations of the Company under the Notes
         and this Indenture pursuant to a supplemental indenture or other
         written agreement, as the case may be, in a form reasonably
         satisfactory to the Trustee. Any Restricted Subsidiary that is a
         Guarantor may consolidate with, merge into or transfer all or part of
         its properties and assets to the Company or another Restricted
         Subsidiary that is a Guarantor.

                  In the event of any transaction (other than a lease) described
         in and complying with the conditions listed in the immediately
         preceding paragraph in which the Company or a Guarantor is not the
         Surviving Person, such Surviving Person shall succeed to, and be
         substituted for, and may exercise every right and power of, the
         Company, and the Company shall be discharged from its obligations
         under, this Indenture and the Notes.

                  (b)      The definitions of any and all terms that are defined
in Section 1.01 but used only in Amended Section 5.1(a) are deleted in their
entireties.

                  SECTION 2.3   Amendment of Section 6.1.

                  (a)      Section 6.1 of the Indenture ("Amended Section 6.1")
is hereby amended by deleting the language in Section 6.1 in its entirety and
replacing it with the following:

                           "Events of Default", wherever used herein, means any
         one of the following events (whatever the reason for such Event of
         Default and whether it shall be voluntary or involuntary or be effected
         by operation of law or pursuant to any judgment, decree or order of any
         court or any order, rule, or regulation of any administrative or
         governmental body):


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                  (i)      the Company defaults in the payment when due of
         interest (including the issuance of Additional PIK Notes) on any Note
         and, in the case of cash interest, such default continues for a period
         of 30 days; or

                  (ii)     the Company defaults in the payment when due of
         principal on any Note, whether upon maturity, acceleration, optional or
         mandatory redemption, required repurchase or otherwise.

                  The Company shall provide an Officers' Certificate to the
         Trustee within five days of the occurrence of any Default or Event of
         Default that has occurred and, if applicable, describe such Default or
         Event of Default and the status thereof.

                  (b)      The definitions of any and all terms that are defined
in Section 1.01 but used only in Amended Section 6.1 are deleted in their
entireties.

                  SECTION 2.4 Amendment of Section 6.2. Section 6.2 of the
Indenture ("Amended Section 6.2") is hereby amended by deleting the language in
Section 6.2 in its entirety and replacing it with the following:

                  (a)      If any Event of Default occurs and is continuing, the
         Trustee or the Holders of at least 25% in aggregate principal amount of
         the then outstanding Notes may, and the Trustee at the request of such
         Holders shall, declare all the Notes to be due and payable immediately
         by notice in writing to the Company, and to the Company and the Trustee
         if by the Holders, specifying the respective Event of Default and that
         such notice is a "notice of acceleration," and the Notes shall become
         immediately due and payable. Following the delivery of such a notice of
         acceleration, any interest that would have otherwise been payable
         through the issuance of Additional PIK Notes shall be payable in cash.

                  (b)      Any time after a declaration of acceleration, but
         before a judgment or decree for payment of the money due has been
         obtained by the Trustee, the Holders of a majority in principal amount
         of the Notes outstanding, by written notice to the Company and the
         Trustee, may rescind and annul such declaration and its consequences if
         (i) the Company has paid or deposited with the Trustee a sum sufficient
         to pay (A) all sums paid or advanced by the Trustee and the reasonable
         compensation, expenses, disbursements and advances of the Trustee, its
         agents and counsel, (B) all overdue interest on all Notes, (C) the
         principal of and premium, if any, on any Notes which have become due
         otherwise than by such declaration or occurrence of acceleration and
         interest thereon at the rate borne by the Notes, and (D) to the extent
         that payment of such interest is lawful, interest upon overdue interest
         at the Default Rate; and (ii) all Events of Default, other than the
         non-payment of principal of Notes which have become due solely by such
         declaration or occurrence of acceleration, have been cured or waived;
         and (iii) the rescission would not conflict with any judgment, order or
         decree of any court of competent jurisdiction.

                  (c)      The Holders of a majority in aggregate principal
         amount of the Notes then outstanding by notice to the Trustee may, on
         behalf of the Holders of all of the Notes, waive any existing Default
         or Event of Default and its consequences under this Indenture except
         (i) a continuing Default or Event of Default in the payment of the
         principal of, or premium, if any, or interest on, the Notes (which may
         be waived only with the consent of


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         each Holder of Notes affected), or (ii) in respect of a covenant or
         provision which under this Indenture cannot be modified or amended
         without the consent of the Holder of each affected Note outstanding.

         SECTION 3. Operation of Amendments. Upon the execution and delivery of
this Supplemental Indenture by the parties hereto, the Supplemental Indenture
will become effective but the Amendments will not become operative until a
majority in outstanding principal amount of the Notes are validly tendered and
accepted pursuant to and in accordance with the terms and conditions of the
offer to purchase as set forth in the Offer to Purchase and Consent Solicitation
of the Company, dated September 30, 2004, and the related Offering Materials (as
such term is defined in the above-mentioned Offer to Purchase and Consent
Solicitation), in each case, as the same may be amended, modified or
supplemented from time to time in accordance therewith.

         SECTION 4. Miscellaneous.

                  SECTION 4.1 Incorporation of the Indenture. All the provisions
of this Supplemental Indenture shall be deemed to be incorporated in, and made a
part of, the Indenture; and the Indenture, as supplemented and amended by this
Supplemental Indenture, shall be read, taken and construed as one and the same
instrument.

                  SECTION 4.2 Application of Supplemental Indenture. The
provisions and benefit of this Supplemental Indenture shall be effective with
respect to the Notes. Except as expressly supplemented or amended as set forth
in this Supplemental Indenture, the Indenture is hereby ratified and confirmed,
and all the terms, provisions and conditions thereof shall be and continue in
full force and effect. The Trustee accepts the trusts created by the Indenture,
as amended and supplemented by this Supplemental Indenture, and agrees to
perform the same upon the terms and conditions in the Indenture as amended and
supplemented by this Supplemental Indenture.

                  SECTION 4.3 Counterparts. The Supplemental Indenture may be
executed in any number of counterparts, each of which so executed shall be
deemed to be an original, but all such counterparts shall together constitute
but one and the same instrument.

                  SECTION 4.4 Successors and Assigns. All agreements in this
Supplemental Indenture by the Company shall bind its successors and assigns,
whether so expressed or not.

                  SECTION 4.5 Severability. In case any one or more of the
provisions in this Supplemental Indenture shall be held invalid, illegal or
unenforceable, in any respect for any reason, the validity, legality and
enforceability of any such provision in every other respect and of the remaining
provisions shall not in any way be affected or impaired thereby, it being
intended that all provisions hereof shall be enforceable to the fullest extent
permitted by law.

                  SECTION 4.6 Benefits of Supplemental Indenture. Nothing in
this Supplemental Indenture, express or implied, shall give to any person, other
than the parties hereto and their successors hereunder and the Holders, any
benefit or any legal or equitable right, remedy or claim under this Supplemental
Indenture.

                  SECTION 4.7 Regarding the Trustee. The Trustee shall not be
responsible for the correctness of the recitals herein, and makes no
representation as to the validity or the sufficiency of this Supplemental
Indenture, except with respect to the execution hereof by the


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Trustee. The Trustee shall, in connection with this Supplemental Indenture, be
entitled to all of the benefits of all of the rights, privileges, immunities and
indemnities of the Trustee provided for in the Indenture.

                  SECTION 4.8 GOVERNING LAW. THIS SUPPLEMENTAL INDENTURE SHALL
BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF OHIO AS
APPLIED TO CONTRACTS MADE AND PERFORMED WITHIN THE STATE OF OHIO WITHOUT REGARD
TO ITS PRINCIPLES OF CONFLICT OF LAWS. Each of the parties hereto agrees to
submit to the jurisdiction of the courts of the State of Ohio in any action or
proceeding arising out of or relating to this Supplemental Indenture.

                  SECTION 4.9 Effect of Headings. The Section headings herein
are for convenience only and shall not affect the construction hereof.



                            [Signature Pages Follow]



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         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the day first written above.


HAWK CORPORATION                          HSBC BANK USA, NATIONAL ASSOCIATION,
                                          as Trustee

By: /s/ Ronald E. Weinberg
    ----------------------------
Name:  Ronald E. Weinberg                 By: /s/Frank J. Godino
Title: Chairman                                  ------------------------------
                                          Name:  Frank J. Godino
                                          Title: Vice President


FRICTION PRODUCTS CO.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



LOGAN METAL STAMPINGS, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:  Ronald E. Weinberg
Title: Chairman



HELSEL, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman


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S.K. WELLMAN HOLDINGS, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:  Ronald E. Weinberg
Title: Chairman



S.K. WELLMAN CORP.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



ALLEGHENY CLEARFIELD, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



HAWK MIM, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:  Ronald E. Weinberg
Title: Chairman



HAWK MOTORS, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman


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HAWK PRECISION COMPONENTS GROUP, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:  Ronald E. Weinberg
Title: Chairman



NET SHAPE TECHNOLOGIES LLC


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



QUARTER MASTER INDUSTRIES, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



SINTERLOY CORPORATION


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



TEX RACING ENTERPRISES, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman


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WELLMAN PRODUCTS GROUP, INC.


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman



WELLMAN PRODUCTS, LLC


By: /s/ Ronald E. Weinberg
    ----------------------------
Name:   Ronald E. Weinberg
Title:  Chairman


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