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                                                                     EXHIBIT 4.1



                AMENDMENT NO. 4 TO CREDIT AND SECURITY AGREEMENT
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         This Amendment No. 4 to Credit and Security Agreement ("Amendment
No. 4") dated effective as of the 29 day of April, 2002, by and between COHESANT
TECHNOLOGIES INC., a Delaware corporation (hereinafter referred to as
"Borrower"), and UNION PLANTERS BANK, N.A. a national banking association
(hereinafter referred to as "Bank").

                              W I T N E S S E T H :

         WHEREAS, the Borrower and the Bank are parties to that certain Credit
and Security Agreement dated as of the 15th day of May, 1998, as amended by that
certain Amendment No. 1 to Credit and Security Agreement dated April 13, 1999,
as further amended by that certain Amendment No. 2 to Credit and Security
Agreement dated April 17, 2000, and as further amended by that certain Amendment
No. 3 to Credit and Security Agreement dated April 1, 2001 (hereinafter referred
to as "Agreement"); and

         WHEREAS, the Borrower desires to renew and amend the financial
accommodations previously extended by the Bank; and

         WHEREAS, the Bank is willing to provide such financial accommodations
to the Borrower on the terms and subject to the conditions in the Agreement as
amended by the terms and conditions of this Amendment No. 4.

         NOW, THEREFORE, in consideration of the premises, the mutual covenants
hereinafter contained, and other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties agree as follows:

         SECTION 1. EFFECT OF THIS AMENDMENT NO. 4. This Amendment No.4 shall
not change, modify, amend or revise the terms, conditions and provisions of the
Agreement, the terms and provisions of which are incorporated herein by
reference, except as expressly provided herein and agreed upon by the parties
hereto. This Amendment No. 4 is not intended to be nor shall it constitute a
novation or accord and satisfaction of the outstanding instruments by and
between the parties hereto. Borrower and Bank agree that, except as expressly
provided herein, all terms and conditions of the Agreement shall remain and
continue in full force and effect. The Borrower acknowledges and agrees that the
indebtedness under the Agreement remains outstanding and is not extinguished,
paid, or retired by this Amendment No. 4, or any other agreements between the
parties hereto prior to the date hereof, and that Borrower is and continues to
be fully liable for all obligations to the Bank contemplated by or arising out
of the Agreement. Except as expressly provided otherwise by this Amendment No.
4, the credit facilities contemplated by this Amendment No. 4 shall be made
according to and pursuant to all conditions, covenants, representations and
warranties contained in the Agreement.

         SECTION 2. DEFINITIONS. Terms defined in the Agreement which are used
herein shall have the same meaning as set forth in the Agreement unless
otherwise specified herein.




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         SECTION 3. AMENDMENT OF AGREEMENT. Subject to the satisfaction of the
conditions precedent set forth in Section 5 herein:

         (a) The first sentence of Subsection 2.1.1 of the Agreement is hereby
amended and replaced with the following:

         2.1.1 The obligation of the Borrower to repay the Line of Credit Loans
         shall be evidenced by the Line of Credit Note which shall be repayable
         on or before May 1, 2003 ("Maturity").

         (b) Borrower and Bank have agreed that the repayment of the Loans and
any other indebtedness or other obligations of the Borrower to the Bank shall,
effective as of the date of this Amendment No. 4, be unsecured. Accordingly,
Section 4 of the Agreement and any other references to collateral security
appearing within the Agreement are hereby deleted in their entirety.

         (c) Sections 6.4, 6.14, 7.10 and 13.3 of the Agreement are hereby
deleted in their entirety.

         (d) Section 7.12.2 of the Agreement is hereby amended and restated in
its entirety as follows:

         7.12.2   RATIO OF TOTAL LIABILITIES TO TANGIBLE NET WORTH. Maintain a
                  ratio of Total Liabilities to Tangible Net Worth at all times
                  in an amount not to exceed 1.00:1.00.

         SECTION 4. CONDITIONS PRECEDENT. This Amendment No.4 shall become and
be deemed effective in accordance with its terms immediately upon the Bank
receiving:

                  (a) Two (2) copies of this Amendment No. 4 duly executed by
         the authorized officers of the Borrower and the Bank.

                  (b) One (1) copy of the Line of Credit Note reflecting the
         revised Maturity duly executed by an authorized officer of the
         Borrower.

                  (c) Two (2) copies of a Consent and Confirmation of Guaranty
         executed by each of the Guarantors.

                  (d) Certificates of Existence regarding Borrower and
         Guarantors issued by the appropriate Secretary of State's Office.

                  (e) Two (2) copies of a Termination of Collateral Agreements
         executed by the duly authorized officers of the Borrower, the
         Guarantors and the Bank.

                  (f) Two (2) copies of an Officer's Certificate Regarding
         Resolutions and Incumbency of Borrower.

                  (g) Such other documents and items as the Bank may reasonably
         request.

         SECTION 5. REPRESENTATIONS AND WARRANTIES OF THE BORROWER. The Borrower
hereby represents and warrants, in addition to any other representations and
warranties contained herein, in the Agreement, the Loan Documents (as defined in
the Agreement) or any other document, writing or statement delivered or mailed
to the Bank or its agent by the Borrower, as follows:




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                  (a) This Amendment No. 4constitutes a legal, valid and binding
         obligation of the Borrower enforceable in accordance with its terms.
         The Borrower has taken all necessary and appropriate corporate action
         for the approval of this Amendment No. 4 and the authorization of the
         execution, delivery and performance thereof.

                  (b) As of the date hereof, there is no Event of Default or
         Default under the Agreement, the Amendment No. 4 or the Loan Documents.

                  (c) The Borrower hereby specifically confirms and ratifies its
         obligations, waivers and consents under each of the Loan Documents.

                  (d) Except as specifically amended herein, all
         representations, warranties and other assertions of fact contained in
         the Agreement and the Loan Documents continue to be true, accurate and
         complete.

                  (e) There have been no changes to the Articles of
         Incorporation, By-Laws, or the composition of the Board of Directors of
         the Borrower since execution of the Agreement.

                  (f) Borrower acknowledges that the definition "Loan Documents"
         shall include this Amendment No. 4 and all the documents executed
         contemporaneously herewith.

         SECTION 6. AFFIRMATIVE COVENANTS. By entering into this Amendment No.
4, Borrower further specifically undertakes to comply with the obligations,
terms and covenants as contained in the Agreement and agrees to comply therewith
as such relate to the credit facilities and accommodations as provided to the
Borrower pursuant to the terms of this Amendment No. 4.

         SECTION 7. GOVERNING LAW. This Amendment No. 4 has been executed and
delivered and is intended to be performed in the State of Indiana and shall be
governed, construed and enforced in all respects in accordance with the
substantive laws of the State of Indiana.

         SECTION 8. HEADINGS. The section headings used in this Amendment No. 4
are for convenience only and shall not be read or construed as limiting the
substance or generality of this Amendment No. 4.

         SECTION 9. SURVIVAL. All representations, warranties, and covenants of
the Borrower herein or any certificate, agreement or other instrument delivered
by or on its behalf under this Amendment No. 4 shall be considered to have been
relied upon by the Bank and shall survive the making of the Loans and delivery
to the Bank of the Line of Credit Note. All statements and any such certificate
or other instrument shall constitute warranties and representations hereunder by
the Borrower, as the case may be.

         SECTION 10. COUNTERPARTS. This Amendment No. 4 may be signed in one or
more counterparts, each of which shall be considered an original, with the same
effect as if the signatures were upon the same instrument.

         SECTION 11. MODIFICATION. This Amendment No. 4 may be amended,
modified, renewed or extended only by written instrument executed in the manner
of its original execution.

         SECTION 12. WAIVER OF CERTAIN RIGHTS. The Borrower waives acceptance or
notice of acceptance hereof and agrees that the Agreement, this Amendment No. 4,
the Line of Credit Note, and all of the other Loan Documents shall be fully
valid, binding, effective and enforceable as of the






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date hereof, even though this Amendment No. 4 and any one or more of the other
Loan Documents which require the signature of the Bank, may be executed by and
on behalf of the Bank on other than the date hereof.

         SECTION 13. WAIVER OF DEFENSES AND CLAIMS. In consideration of the
financial accommodations provided to the Borrower by the Bank as contemplated by
this Amendment No. 4, Borrower hereby waives, releases and forever discharges
the Bank from and against any and all rights, claims or causes of action against
the Bank arising under the Bank's actions or inactions with respect to the Loan
Documents or any security interest, lien or collateral in connection therewith
as well as any and all rights of set off, defenses, claims, causes of action and
any other bar to the enforcement of the Loan Documents which exist as of the
date hereof.

         IN WITNESS WHEREOF, COHESANT TECHNOLOGIES INC. and UNION PLANTERS BANK,
N.A. have caused this Amendment No. 4 to Credit and Security Agreement to be
executed by their respective duly authorized officers effective as of the 29 day
of April, 2002.

                                       COHESANT TECHNOLOGIES INC.

                                       ("Borrower")

                                       By:_____________________________________

                                       Printed:________________________________

                                       Title:__________________________________


                                       UNION PLANTERS BANK, N.A.

                                       ("Bank")


                                       By:_____________________________________
                                          Janet K. Carter, Vice President







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