Document:

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                                                                     Exhibit 4.1
                                                                     -----------

                       [Letterhead of Penton Media, Inc.]

                                  July 31, 2002

National City Bank
Corporate Trust Administration
629 Euclid Avenue, Suite 635
Cleveland, Ohio 44114

Attention:  Laura Kress

              Re: Amendment No. 2 to Rights Agreement
                  -----------------------------------

Ladies and Gentlemen:

     Pursuant to Section 27 of the Rights Agreement, as amended (the "Rights
Agreement"), dated as of June 9, 2000, between Penton Media, Inc. (the
"Company"), and National City Bank, as successor rights agent to Harris Trust
and Savings Bank, the Company, by resolution adopted by its Directors, hereby
amends the Rights Agreement as follows:

     1. Section 1(j) of the Rights Agreement is hereby amended by deleting the
current section and replacing it with the following language:

     "(j) `EXPIRATION DATE' means the earliest of (i) the Close of Business on
     the Final Expiration Date, (ii) the time at which the Rights are redeemed
     as provided in SECTION 23, (iii) the time at which all exercisable Rights
     are exchanged as provided in SECTION 24, and (iv) if the Rights Agreement
     has not been approved by the affirmative vote of a majority of the votes
     cast of the Company's capital stock entitled to vote thereon at a meeting
     of the stockholders to be held not later than the annual meeting of the
     Company's stockholders to be held in 2003 (or any adjournment or
     postponement thereof), at the Close of Business on the day of such annual
     meeting (or any adjournment or postponement thereof).

     2. The Rights Agreement shall not otherwise be supplemented or amended by
virtue of this Amendment No. 2 to the Rights Agreement, but shall remain in full
force and effect.

     3. Capitalized terms used without other definition in this Amendment No. 2
to the Rights Agreement shall be used as defined in the Rights Agreement.

     4. This Amendment No. 2 to the Rights Agreement shall be deemed to be a
contract made under the laws of the State of Delaware and for all purposes shall
be governed by and construed in accordance with the laws of such State
applicable to contracts to be made and to be performed entirely within Delaware.

<PAGE>

National City Bank
July 31, 2002
Page 2

     5. This Amendment No. 2 to the Rights Agreement may be executed in any
number of counterparts and each of such counterparts shall for all purposes be
deemed to be an original, and all such counterparts shall together constitute
but one and the same instrument.

     6. This Amendment No. 2 to the Rights Agreement shall be effective as of,
and immediately prior to, the execution and delivery of this amendment, and all
references to the Rights Agreement shall, from and after such time, be deemed to
be references to the Rights Agreement as amended hereby.

     7. Exhibits B and C to the Rights Agreement shall be deemed amended in a
manner consistent with this Amendment No. 2 to the Rights Agreement.

                                      Very truly yours,

                                      PENTON MEDIA, INC.

                                      By: /s/ Preston L. Vice
                                         _________________________________
                                         Name: Preston L. Vice
                                         Title: Senior Vice President

                                      Accepted and Agreed to as of the effective
                                      time specified above.

                                      NATIONAL CITY BANK

                                      By: /s/ Laura Kress
                                         _________________________________
                                         Name: Laura Kress
                                         Title: Vice President<PAGE>
                                                                     Exhibit 4.6
                                                                     -----------

                             SUPPLEMENTAL INDENTURE

         SUPPLEMENTAL INDENTURE (this "Supplemental Indenture") dated as of
[August __, 2002], among Hawk Corporation, a Delaware corporation (the
"Company"); and Allegheny Clearfield, Inc., Hawk MIM, Inc., Hawk Motors, Inc.,
Hawk Precision Components Group, Inc., Net Shape Technologies LLC, Quarter
Master Industries, Inc., Tex Racing Enterprises, Inc., Friction Products Co.,
Logan Metal Stampings, Inc., S.K. Wellman Holdings, Inc., S.K. Wellman Corp.,
Sinterloy Corporation and Helsel, Inc. (each a "Guarantor" and collectively the
"Guarantors", and HSBC Bank USA, a banking corporation and trust company duly
organized and existing under the laws of the State of New York, as successor
trustee, (the "Trustee"), successor to Bank One Trust Company, N.A., a national
banking association (the "Prior Trustee").

                                    RECITALS

         WHEREAS, the Company, the Guarantors and the Prior Trustee have
heretofore executed and delivered a certain Indenture, dated as of November 27,
1996 (as amended or supplemented from time to time prior to the date hereof, the
"Indenture") with respect to the Company's Series A 10.25% Senior Notes due
December 1, 2003 and Series B 10.25% Senior Notes due December 1, 2002
(collectively, the "Notes"), and together with the Trustee have executed a
Resignation, Appointment and Acceptance Agreement, dated as of April 25, 2002,
appointing the Trustee as successor trustee;

         WHEREAS, Section 9.2 of the Indenture provides that, subject to Section
6.7 of the Indenture, the Company and the Guarantors, when authorized by a Board
Resolution, and the Trustee, together, with the written consent of the Holder or
Holders of not less than a majority in aggregate principal amount of the then
outstanding Notes (including consents obtained in connection with a tender offer
or exchange offer for the Notes), may amend or supplement the Indenture, the
Notes and the Guarantees without notice to any other Holder;

         WHEREAS, the Company has offered to exchange all of the outstanding
Notes, upon the terms and subject to the conditions set forth in its Prospectus
and Consent Solicitation Statement, dated [August __, 2002], and in the related
Letter of Transmittal and Consent (the "Exchange Offer"), and in connection
therewith, the Company has been soliciting written consents of the Holders to
the amendments to the Indenture set forth herein (and to the execution of this
Supplemental Indenture), and the Company has now obtained such written consents
from the Holders of a majority in principal amount of the outstanding Notes;
accordingly, this Supplemental Indenture and the amendments set forth herein are
authorized pursuant to Section 9.2 of the Indenture; and

         WHEREAS, the execution and delivery of this Supplemental Indenture has
been duly authorized by the parties hereto, and all other acts necessary to make
this Supplemental Indenture a valid and binding supplement to the Indenture,
effectively amending and supplementing the Indenture as set forth herein, have
been duly taken;

<PAGE>

         NOW, THEREFORE, in consideration of the above premises and for other
good and valuable consideration, the receipt of which is hereby acknowledged, it
is mutually agreed, for the equal and proportionate benefit of all Holders, as
follows:

                                  ARTICLE ONE

         Upon consummation of the exchange by the Company of all Notes validly
tendered pursuant to the Exchange Offer and not withdrawn before the expiration
date for such Exchange Offer (as notified to the Trustee by the Company upon
which notification the Trustee may rely), then automatically (without further
act by any person) with respect to all outstanding Notes, the Indenture is
amended in the following respects:

1.1      Sections 4.3, 4.4, 4.5, 4.8, 4.10, 4.11, 4.12, 4.13, 4.14, 4.15, 4.16,
6.1(iv), 6.1(v), 6.1(vi), 6.1(vii), 6.1(viii), 10.1, 10.2, 10.3, 10.4, 10.5,
10.6, 10.7, 10.8, 10.9 and 10.10 of the Indenture and all other references to
these sections in the Indenture and the Notes shall be deleted and each of the
Company and the Guarantors shall be released from its respective obligations
thereunder.

1.2      Any failure by the Company or the Guarantors to comply with the terms
of any of the foregoing Sections of the Indenture (whether before or after the
execution of this Supplemental Indenture) shall no longer constitute a default
or an Event of Default under the Indenture and shall no longer have any other
consequence under the Indenture.

1.3      The Guarantees and all referenced thereto in the Notes shall be deleted
in their entirety. On behalf of itself, each of the Holders and their respective
heirs, beneficiaries, estates, representatives, affiliates, successors and
assigns, the Trustee shall fully and unconditionally (i) release each of the
Guarantors from all Obligations arising under its Guarantee, and (ii) release
and extinguish all of the Guarantees, which shall not hereafter be deemed
outstanding for any purpose whatsoever.

1.4      Section 4.9 of the Indenture shall be deleted in its entirely, and the
following is substituted in lieu thereof:

                  "Section 4.9 Compliance with the TIA.

                           Upon qualification of this Indenture under the TIA,
                  the Company shall comply with the provisions of TIA Section
                  314 (a)."

1.5      Section 4.17(a)(ii) of the Indenture shall be deleted in its entirely,
and the following is substituted in lieu thereof:

                  "intentionally omitted."

1.6      The second paragraph of Section 4.17(a)(iii) of the Indenture shall be
deleted in its entirety.

1.7      Section 5.1(a) of the Indenture shall be deleted in its entirety, and
the following is substituted in lieu thereof:

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                  "Section 5.1 Merger, Consolidation and Sale of Assets.

                  (a) 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)
         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;

                  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 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."

1.8      Section 6.1(iii) of the Indenture shall be deleted in its entirety, and
the following is substituted in lieu thereof:

                  "(iii) the Company's failure to perform or comply with any
         covenant, agreement or warranty in this Indenture (other than the
         defaults specified in clauses (i) and (ii) above) which failure
         continues for 60 days after written notice thereof has been given to
         the Company by the Trustee or to the Company and the Trustee by the
         Holders of at least 25% in aggregate principal amount of the then
         outstanding Notes;"

1.9      Section 6.2(a) of the Indenture shall be deleted in its entirety, and
the following is substituted in lieu thereof:

                  "(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 Notes shall become
         immediately due and payable."

1.10     Section 6.2(b) of the Indenture shall be deleted in its entirety, and
the following is substituted in lieu thereof:

                  "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

                                       3
<PAGE>

                  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 rate borne by the Notes; 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."

1.11     Section 8.2(b) of the Indenture shall be deleted in its entirety, and
the following is substituted in lieu thereof:

                  "Subject to the satisfaction of the conditions in Section
                  8.2(c) hereof, the Company may, at its option by Board
                  Resolution, at any time, elect to effect covenant defeasance
                  ("Covenant Defeasance"). On and after the date such conditions
                  are satisfied, (i) the Company shall be released from its
                  obligations under any covenant or provision contained in
                  Sections 4.6(a), 4.7, 4.9 and 4.17 through 4.19, (ii) clause
                  (iii) of Section 6.1 hereof shall not apply, and (iii) the
                  provisions of Articles Five and Eleven shall not apply, and
                  the Notes shall thereafter be deemed to be not "outstanding"
                  for the purposes of any direction, waiver, consent or
                  declaration or act of Holders (and the consequences of any
                  thereof) in connection with such covenants and the provisions
                  of Articles Five and Eleven, but shall continue to be deemed
                  "outstanding" for all other purposes hereunder. For this
                  purpose, such covenant defeasance means that, with respect to
                  the Notes, the Company may omit to comply with and shall have
                  no liability in respect of any term, condition or limitation
                  set forth in any such Section or Article, whether directly or
                  indirectly, by reason of any reference elsewhere herein to any
                  such Section or Article or by reason of any reference in any
                  such Section or Article to any other provision herein or in
                  any other document and such omission to comply shall not
                  constitute a Default or an Event of Default under clause (iii)
                  of Section 6.1 hereof, but, except as specified above, the
                  remainder of this Indenture shall be unaffected thereby."

1.12     In connection with the amendments identified above, the following
defined terms used in Section 1.1 of the Indenture, and all references to such
defined terms in the Indenture and the Notes shall be deleted: Acquired Debt;
Asset Sale; Asset Sale Offer; Asset Sale Offer Trigger Date; Asset Sale Offer
Purchase Date; Bankruptcy Law; Cash Equivalents; Cash Flow; Change of Control;
Change of Control Offer; Change of Control Purchase Date; Consolidated Cash Flow
Coverage Ratio; Consolidated Interest Expense; Consolidated Net Worth; Excess
Proceeds;

                                       4
<PAGE>

Existing Indebtedness; Guarantee; Guarantor; Hawk Controlling Stockholder
Merger; Independent Director; Internal Revenue Code; Net Proceeds; Permitted
Indebtedness; Permitted Investments; Permitted Holders; Permitted Liens;
Permitted Payments; Refinancing; Refinancing Indebtedness; Required Filing
Dates; Restricted Investment; Restricted Payment; and Weighted Average Life to
Maturity.

1.13     In connection with the amendments identified above, the defined term
"Consolidated Net Income" shall be deleted in its entirety, and the following is
substituted in lieu thereof.

                  ""Consolidated Net Income" means, with respect to any period,
         the net income (or loss) of the Company and its Restricted Subsidiaries
         for such period, determined on a consolidated basis in accordance with
         GAAP consistently applied, adjusted to the extent included in
         calculating such net income (or loss), by excluding, without
         duplication, (i) all extraordinary gains and losses (less all fees and
         expenses relating thereto), (ii) the portion of net income (or loss) of
         the Company and its Restricted Subsidiaries allocable to interests in
         unconsolidated Persons or Unrestricted Subsidiaries, except to the
         extent of the amount of dividends or distributions actually paid to the
         Company or its Restricted Subsidiaries by such other Person during such
         period, (iii) net gains and losses (less all fees and expenses relating
         thereto) in respect of disposition of assets (including, without
         limitation, pursuant to sale and leaseback transactions) other than in
         the ordinary course of business, or (iv) the net income of any
         Restricted Subsidiary to the extent that the declaration of dividends
         or similar distributions by that Restricted Subsidiary of that income
         to the Company is not at the time permitted, directly or indirectly, by
         operation of the terms of its charter or any agreement, instrument,
         judgment, decree, order, statute, rule or governmental regulation
         applicable to that Restricted Subsidiary or its stockholders."

1.14     In connection with the amendments identified above, the defined term
"incur" used in Section 1.1 of the Indenture shall be deleted in its entirety,
and the following is substituted in lieu thereof:

                  ""incur" means to create, incur, issue, assume or directly or
         indirectly guarantee or in any other manner become directly or
         indirectly liable for."

1.15     In connection with the amendments identified above, the defined term
"Investment" used in Section 1.1 of the Indenture shall be deleted in its
entirety and the following is substituted in lieu thereof:

                  ""Investment means, with respect to any Person, any direct or
         indirect loan or other extension of credit (including, without
         limitation, a guarantee) or capital contribution to (by means of any
         transfer of cash or other property to others or any payment for
         property or services for the account or use of others), or any purchase
         or acquisition by such Person of any Capital Stock, bonds, notes,
         debentures or other securities or evidences of Indebtedness issued by,
         any other Person. "Investment" shall exclude travel and similar
         advances to officers and employees of the Company in the ordinary
         course of business and extensions of trade credit by the Company and
         its

                                       5
<PAGE>
         Restricted Subsidiaries on commercially reasonable terms in accordance
         with normal trade practices of the Company or such Restricted
         Subsidiary, as the case may be."

                                  ARTICLE TWO

2.1      All terms used in this Supplemental Indenture which are defined in the
Indenture and not otherwise defined herein shall have the meanings assigned to
such terms in the Indenture.

2.2      All of the provisions of this Supplemental Indenture shall be deemed to
be incorporated in, and made part of, the Indenture, and the Indenture, as
amended and supplemented by this Supplemental Indenture, shall be read, taken
and construed as one and the same instrument and shall be binding upon all the
Holders.

2.3      This 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.

2.4      In case any provision in this Supplemental Indenture shall be invalid,
illegal or unenforceable, the validity, legality and enforceability of the
remaining provisions shall not in any way be affected or impaired thereby.

2.5      Nothing in this Supplemental Indenture, express or implied, shall give
any person, other that 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. 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.

2.6      The Trustee shall not be responsible in any matter whatsoever for or in
respect of the validity or sufficiency of this Supplemental Indenture, except
with respect to the execution hereof by the Trustee, or for or in respect of the
recitals contained herein, all of which are made solely by the Company and the
Guarantors.

2.7      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.

                                       6
<PAGE>

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

                                HAWK CORPORATION

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

                                FRICTION PRODUCTS CO.

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

                                LOGAN METAL STAMPINGS, INC.

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

                                HELSEL, INC.

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

                                S.K. WELLMAN HOLDINGS, INC.

                                By:
                                   ---------------------------------
                                    Name: Ronald E. Weinberg

                                       7
<PAGE>
                                ALLEGHENY CLEARFIELD, INC.

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

                                HAWK MIM, INC.

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

                                HAWK MOTORS, INC.

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

                                HAWK PRECISION COMPONENTS GROUP, INC.

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

                                NET SHAPE TECHNOLOGIES LLC

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

                                       8
<PAGE>
                                QUARTER MASTER INDUSTRIES, INC.

                                By:
                                   ---------------------------------

                                    Name: Ronald E. Weinberg
                                    Title: Chairman

                                SINTERLOY CORPORATION

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

                                TEX RACING ENTERPRISES, INC.

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

                                HSBC BANK USA, AS TRUSTEE

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

                                       9

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