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                                                                    Exhibit 4.1


                AMENDMENT NO. 1 TO CREDIT AND SECURITY AGREEMENT
                ------------------------------------------------


         This Amendment No. 1 to Credit and Security Agreement ("Amendment No.
1") dated as of this    day of April, 1999, 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") as successor in interest by way of assignment to NBD BANK, N.A.

                              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 (hereinafter
referred to as "Agreement"); and

         WHEREAS, the Borrower desires to renew 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. 1.

         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. 1. This Amendment No. 1 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. 1 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. 1, 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.
1, the credit facilities contemplated by this Amendment No. 1 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.

         SECTION 3. AMENDMENT OF AGREEMENT. Subject to the satisfaction of the
conditions


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precedent set forth in Section 5 herein:

         (a) All references to "Bank" appearing in the Agreement and the Loan
Documents shall hereinafter refer to Union Planters Bank, N.A.

         (b) 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, 2000 ("Maturity").

         (c) Section 2.2 of the Agreement is hereby amended and restated in its
entirety with the following:

         2.2   STANDBY LETTERS OF CREDIT. The Borrower may apply to the Bank for
         the issuance by the Bank of one or more Letters of Credit
         (individually a "Letter of Credit" and collectively the "Letters of
         Credit"), the aggregate maximum principal amount of such Letters of
         Credit not to exceed One Hundred Thousand and No/100 Dollars
         ($100,000.00). Upon receipt by the Bank of a duly executed application
         by the Borrower for a Letter of Credit on the Bank's standard form
         therefor, the Bank will accept such applications and issue one or more
         of its Letters of Credit, subject to availability under the Line of
         Credit. The Borrower agrees to pay the Bank a fee of One Percent
         (1.0%) per annum for the aggregate undrawn full amount of the Letters
         of Credit, which fee shall be paid on or prior to the issuance of a
         Letter of Credit and thereafter on or before the renewal thereof. This
         fee shall be additional consideration for the issuance of the Letter
         of Credit. The Borrower shall not be entitled to, and agrees not to
         seek, any refund, credit or offset for such fee whether or not any
         amounts are drawn under any of such Letters of Credit. The terms and
         conditions of the Letters of Credit shall be governed by International
         Standby Practices - ISP98 (1998 version) International Chamber of
         Commerce Publication No. 590 and otherwise in accordance with their
         terms. The terms and conditions of any obligations of the Borrower
         pursuant to any such Letter of Credit shall be determined by the
         application made by the Borrower as accepted by the Bank. The Borrower
         acknowledges that the amount available under the Borrowing Base shall
         be reduced by the sum of (i) aggregate undrawn face amount of any
         Letters of Credit plus (ii) the aggregate of any amounts paid by the
         Bank pursuant to any Letter of Credit.

         (d) The address for purposes of notices to the Bank as set forth in
Section 13.11 of the Agreement is hereby amended as follows:

                  If to Bank:               Union Planters Bank, N.A.


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                                            One Indiana Square
                                            Mail Station 728
                                            Indianapolis, Indiana  46266
                                            Attn:  Janet K. Carter
                                            Telecopy:  (317) 221-6921

         SECTION 4. COMMITMENT FEE AND LEGAL FEES. There will be a Three
Thousand Five Hundred and No/100 Dollar ($3,500.00) commitment fee for the
renewal of the credit facilities contemplated by this Amendment No. 1 to the
Borrower. All out-of-pocket expenses of the Bank, including without limitation,
filing fees, recording fees, and legal fees and disbursements, are to be paid by
Borrower promptly upon demand therefor.

         SECTION 5. CONDITIONS PRECEDENT. This Amendment No. 1 shall become and
be deemed effective in accordance with its terms immediately upon the Bank
receiving:

                  (a)  Two (2) copies of this Amendment No. 1 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 the Application for Advance and
         Borrower Base Certificate dated as of the date hereof, in such amount
         as requested to be advanced under the Line of Credit, or, in the
         alternative, a Certificate of No Default, each executed by an
         authorized officer of the Borrower.

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

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

         SECTION 6. 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:

                  (a)  This Amendment No. 1 constitutes 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. 1 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. 1 or the Loan Documents.



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                  (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, the identities of the officers, 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. 1 and all the documents executed
         contemporaneously herewith.

         SECTION 7. AFFIRMATIVE COVENANTS. By entering into this Amendment No.
1, 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. 1.

         SECTION 8. GOVERNING LAW. This Amendment No. 1 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 9. HEADINGS. The section headings used in this Amendment No. 1
are for convenience only and shall not be read or construed as limiting the
substance or generality of this Amendment No. 1.

         SECTION 10. 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. 1 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 11. COUNTERPARTS. This Amendment No. 1 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 12. MODIFICATION. This Amendment No. 1 may be amended,
modified, renewed or extended only by written instrument executed in the manner
of its original execution.

         SECTION 13. WAIVER OF CERTAIN RIGHTS. The Borrower waives acceptance or
notice of acceptance hereof and agrees that the Agreement, this Amendment No. 1,
the Line of Credit



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Note, and all of the other Loan Documents shall be fully valid, binding,
effective and enforceable as of the date hereof, even though this Amendment No.
1 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 14. WAIVER OF DEFENSES AND CLAIMS. In consideration of the
financial accommodations provided to the Borrower by the Bank as contemplated by
this Amendment No. 1, 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. 1 to Credit and Security Agreement to
be executed by their respective duly authorized officers as of this day of
April, 1999.

                                    COHESANT TECHNOLOGIES INC.

                                    ("Borrower")


                                    By:_________________________________________

                                    Printed:____________________________________

                                    Title:______________________________________


                                    UNION PLANTERS BANK, N.A.

                                    ("Bank")


                                    By:_________________________________________
                                       Janet K. Carter, Vice President




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