SECOND SUPPLEMENTAL INDENTURE

                           Dated as of March 15, 2002

                                       to

                                    INDENTURE

                           Dated as of August 7, 1997

                                     between

                     Keystone Consolidated Industries, Inc.

                                   as Issuer,

                                       and

                              The Bank of New York,

                                   as Trustee


                       ----------------------------------

                      9 5/8% Senior Secured Notes due 2007
                       ----------------------------------



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                          SECOND SUPPLEMENTAL INDENTURE

          SECOND  SUPPLEMENTAL  INDENTURE,  dated as of  March  15,  2002  (this
"Supplemental  Indenture"),  between Keystone Consolidated  Industries,  Inc., a
Delaware  corporation  (the  "Company"),  and The Bank of New  York,  a New York
banking  corporation (the  "Trustee"),  to that certain  Indenture,  dated as of
August 7, 1997 (the "Indenture"), between the Company and the Trustee.

          WHEREAS,  the parties  hereto have  entered into the  Indenture  which
provides  for the  issuance by the Company of up to  $100,000,000  in  aggregate
principal amount of 9 5/8% Senior Secured Notes due 2007 (the "Notes");

          WHEREAS, concurrent herewith the Company and the Trustee are executing
that  certain  First  Supplemental  Indenture  dated as of the date  hereof (the
"First  Supplemental  Indenture")  that  provides for certain  amendments to the
Indenture and the Notes;

          WHEREAS, for administrative convenience, the Company wishes to further
amend the  Indenture and the Notes to provide  additional  rights or benefits to
the  Holders of the Notes  with  respect  to the  timely  payment  of  defaulted
interest as hereinafter provided;

          WHEREAS, all acts necessary to constitute this Supplemental  Indenture
as a valid,  binding  and legal  obligation  of the  Company  have been done and
performed; and

          WHEREAS, capitalized terms used herein and not otherwise defined shall
have the meanings given them in the Indenture.

          NOW, THEREFORE, this Supplemental Indenture witnesseth:

          In order to comply with the requirements of the Indenture, the Company
covenants and agrees with the Trustee for the equal and  proportionate  benefit,
security  and  protection  of the  respective  holders  from time to time of the
Notes, as follows:

                                   ARTICLE I.
                                    AMENDMENT

          Section 1.1.  Amendment of Section 2.12. Section 2.12 of the Indenture
shall be amended by adding the following to the end of such section as set forth
in the Indenture:

          "In the event that there shall be less than  $10,000,000  in
          aggregate  principal amount of Notes  outstanding under this
          Indenture,  then notwithstanding  anything contained in this
          Indenture  to the  contrary,  (i) the  special  record  date
          relating to the payment of any defaulted interest may be the
          same as the  payment  date for any such  interest;  and (ii)
          neither the  Company  nor the  Trustee  shall be required to
          give any  advance  notice to any Holder of the fixing of the
          special  record date,  the special  record date, the related
          payment date or the amount of such interest to be paid."

                                   ARTICLE II.
                            MISCELLANEOUS PROVISIONS

          Section 2.1. Unless  otherwise  defined herein,  or unless the context
otherwise  requires,  the terms used herein shall have the  respective  meanings
assigned to them in the Indenture.

          Section  2.2.  The  Trustee  accepts  the trusts in this  Supplemental
Indenture  declared and provided upon the terms and  conditions set forth in the
Indenture.  The Trustee shall not be responsible in any manner whatsoever for or
in respect of the validity or sufficiency of this Supplemental  Indenture or the
due  execution  hereof by the Company or for, or in respect of, the recitals and
statements  contained  herein,  all of which  recitals and  statements  are made
solely by the Company.

          Section 2.3. Upon the  effectiveness of this  Supplemental  Indenture,
all Notes outstanding  immediately prior to such  effectiveness  shall be deemed
amended as  necessary or  appropriate  to reflect the terms and  conditions  set
forth in the Indenture as modified by this  Supplemental  Indenture,  and in the
event  of a  conflict  between  any  term or  condition  of such  Notes  and the
Indenture  as  so  modified,   the  Indenture  as  so  modified  shall  control,
notwithstanding  any  provision of such Notes or the  Indenture to the contrary.
Except as modified by this  Supplemental  Indenture  and the First  Supplemental
Indenture,  the  Indenture  and such  Notes  are in all  respects  ratified  and
confirmed and all of the terms,  conditions and provisions  thereof shall remain
in full force and effect.

          Section  2.4.  The  recitals  contained  herein  shall be taken as the
statements of the Company,  and the Trustee assumes no responsibility  for their
correctness.  The  Trustee  makes  no  representations  as to  the  validity  or
sufficiency of this Supplemental Indenture.

          Section 2.5. This Supplemental  Indenture shall be effective as of the
date first set forth above upon the execution hereof by both parties hereto.

          Section  2.6.  The  parties  may sign  multiple  counterparts  of this
Supplemental   Indenture,   each  of  which  may  be   delivered   by  facsimile
transmission.  Each signed  counterpart shall be deemed an original,  but all of
them together represent the same agreement.

          Section  2.7.  The laws of the  State of New York  shall  govern  this
Supplemental Indenture without regard to principles of conflicts of laws.

          Section 2.8. If any  provision or  subprovision  of this  Supplemental
Indenture  or the  application  thereof to any person or  circumstance  shall be
invalid,  illegal  or  unenforceable  to  any  extent,  the  remainder  of  this
Supplemental  Indenture  and the  application  thereof shall not be affected and
shall be enforceable to the fullest extent permitted by law.


                         [Signatures on following page.]



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

                            KEYSTONE CONSOLIDATED INDUSTRIES, INC.


                            By:
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                               Name:
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                               Title:
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                            THE BANK OF NEW YORK, as Trustee


                            By:
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