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                                                                     Exhibit 4.1



                   UNCONDITIONAL UNLIMITED CONTINUING GUARANTY

         FOR VALUE RECEIVED and in consideration of credit given or to be given,
and of other financial accommodations afforded or to be afforded to GLAS-CRAFT,
INC. (hereinafter referred to as "Borrower"), pursuant to that certain
Promissory Note dated May 13, 1997 and other credit and collateral documents
(hereinafter collectively referred to as "Loan Documents") executed or to be
executed by and between the Borrower and NBD BANK, N.A. (hereinafter referred to
as "Bank"), the receipt and sufficiency of which consideration are hereby
acknowledged, and as an inducement to the Bank to extend such financial
accommodations to the Borrower, COHESANT TECHNOLOGIES INC. (hereinafter referred
to as "Guarantor"), hereby guaranties the full payment, when due, whether by
acceleration or otherwise, of any and all indebtedness which now exists or may
hereafter accrue or arise in any manner from or on behalf of the Borrower to the
Bank and the performance of any and all obligations and liabilities of the
Borrower, or any of them, to the Bank from whatever source or origin and
whenever arising, whether direct, indirect or contingent, whether on open
account, evidenced by an instrument or otherwise, including without limitation
all renewals, extensions and future advances, together with interest at the rate
provided in the note, notes, or other documents evidencing such indebtedness,
together with all costs, expenses and attorneys' fees (the above-described
obligations and the liabilities in addition to any other liabilities or
obligations of the Borrower and Guarantor to Bank which may arise in any manner
are hereinafter referred to as "Liabilities"), all without relief from valuation
and appraisement laws.

         If the Borrower fails to pay or perform all or any part of the
Liabilities when due, then immediately upon demand by Bank, the Guarantor will
pay the amount due and perform the obligations of the Borrower in connection
therewith as if such amount and obligations constituted the direct and primary
debts and obligations of the Guarantor. The Bank shall not be required to make
any demand upon or pursue or exhaust any of its rights or remedies against the
Borrower or others, including without limitation other guarantors, with respect
to the payment or performance of any of the Liabilities or to pursue or exhaust
any of its rights or remedies with respect to any collateral held by the Bank.

         This Guaranty shall be and remain a continuing, unlimited
unconditional, and absolute guaranty. This Guaranty shall remain fully
enforceable irrespective of any defenses which the Borrower may assert on the
underlying Liabilities, including but not limited to failure of consideration,
breach of warranty, statute of frauds, statute of limitations, accord and
satisfaction and usury.

         This Guaranty shall continue in force with respect to the Guarantor
until the Bank receives written notice of the Guarantor's election not to
guaranty any new Liabilities arising after receipt of such notice. Any such
notice shall not in any way affect or limit either (i) the promise of the
Guarantor giving such notice to pay all Liabilities existing at the time such
notice is received by the Bank or (ii) the promises, obligations and
undertakings of the remaining guarantors, if any, with respect to any
Liabilities, including, without limitation, those arising after the date of such
notice. Regardless of when a renewal or extension of pre-termination Liabilities
occurs (with or without adjustment of interest rate or other terms), the
Liabilities shall be deemed to have been incurred prior

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to the termination to the extent of the renewal or extension and to be fully
covered and included within this Guaranty.

         The Guarantor waives (a) notice to the Guarantor or the Borrower or
other guarantors of (i) acceptance of this Guaranty by the Bank, (ii) the
Borrower incurring additional Liabilities, and (iii) the amount of the
Liabilities at any time outstanding; (b) presentment for payment, demand,
protest, notice to the Guarantor, the other guarantors or the Borrower of
dishonor, nonpayment, default and non-performance with respect to any of the
Liabilities; (c) the right to require proration among the Guarantor and other
guarantors; (d) any and all rights to require the Bank to marshall assets of the
Borrower or any other guarantor or other party providing any security for the
Liabilities; (e) any defense which the Borrower or other guarantors may have
against the Bank other than payment; (f) all defenses given to sureties or
guarantors at law or in equity other than payment; and (g) all errors and
omissions in connection with the Bank's administration of the Liabilities,
except actions or inactions which amount to bad faith and willful and wanton
misconduct. All remedies or actions by the Bank for payment or fulfillment of
the Liabilities are cumulative and the pursuit of one shall not preclude the
exercise of any other rights or remedies.

         The Guarantor hereby grants to the Bank full power, in its uncontrolled
discretion and without notice to the Guarantor, the other guarantors, or the
Borrower, to deal in any manner with the Liabilities including, without
limitation, the following powers: (a) to modify or otherwise change any terms of
the Liabilities, or the rate of interest thereon, or to grant any extension or
renewal thereof, and any other indulgence with respect thereto, and to effect
any release, compromise, or settlement with respect thereto; (b) to forbear from
enforcing payment or any term of the Liabilities; or (c) to release any other
guarantor or surety of the Liabilities. The obligations of the Guarantor
hereunder shall not be released, discharged, or in any way affected, nor shall
the Guarantor have any rights or recourse against the Bank by reason of any
action the Bank may take, omit to take, or delay in taking under the foregoing
powers. The obligations of Guarantor under this Guaranty shall be the joint and
several obligations of Guarantor and any other guarantors (now existing or
hereafter arising) of the obligations of the Borrower to the Bank.

         Without limiting the foregoing waivers by the Guarantor of right to
notice, and without obligating the Bank to follow the following procedure if
demand is made after the occurrence of an Event of Default (as defined in the
Loan Documents), the Bank may at any time demand payment from the Guarantor by
mailing to the Guarantor written demand therefor addressed to any address of the
Guarantor in the Bank's records, and in the manner provided for in the Loan
Documents, and the Guarantor agrees that the sending of such written demand as
herein provided shall be a sufficient demand for payment hereunder.

         Whenever possible, each provision of this Guaranty shall be interpreted
in such a manner as to be effective and valid under applicable law, but if such
provision shall be prohibited by or invalid under applicable law, such provision
shall be ineffective to the extent of such prohibition or invalidity, without
invalidating the remainder of such provision or remaining provisions of this or
any related agreement or instrument.

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         Notwithstanding any other terms or conditions set forth in this
Guaranty, the Guarantor waives any claim or other right which it might now have
or hereafter acquire against the Borrower or any other person that is primarily
or contingently liable on the Liabilities that arise from the existence or
performance of the Guarantor's obligations under this Guaranty, including,
without limitation, any right of subrogation, reimbursement, exoneration,
contribution, indemnification, any right to participate in any claim or remedy
of the Bank against the Borrower or any collateral security therefore which the
Bank now has or hereafter acquires; whether or not such claim, remedy or right
arises in equity, or under contract, statute or common law.

         The Guarantor represents to and for the benefit of the Bank, upon which
the Bank is entitled to rely and the Guarantor acknowledges that the Bank is
relying, that (i) the Guarantor is a corporation duly organized and existing
under the laws of the State of Delaware, (ii) the execution, delivery and
performance hereof will not violate any law or any material contract, agreement
or understanding which is binding on the Guarantor, (iii) this Guaranty is the
valid and binding obligation of the Guarantor, enforceable in accordance with
its terms, except as may be limited by bankruptcy, insolvency, reorganization,
moratorium or similar debtor relief laws from time to time in effect and (iv)
the financial statements of Guarantor provided to the Bank are true, accurate
and complete, have been prepared on a consistent basis, and fairly present the
financial position of the Guarantor as of the date thereof.

         The Guarantor agrees to provide annual current, consolidated financial
statements within ninety (90) days following the end of its fiscal year, each
year while the Liabilities are outstanding and such delivery shall constitute
confirmation of the representations, warranties and agreements contained herein
as of the date of each delivery. The Guarantor acknowledges that (i) it is
capable of and responsible for obtaining information on and keeping informed as
to all aspects of the Borrower's business, including without limitation its
financial affairs and business prospects, and the status of the Liabilities from
time to time and (ii) the Bank has no responsibility to so inform the Guarantor.

         The Guarantor acknowledges that separate guaranties may be given in
connection with the Liabilities and this Guaranty shall not be modified,
amended, limited (other than in accordance with the terms hereof), or
extinguished if one or more of the terms of the other guaranty agreements differ
from those of this Guaranty or are subsequently amended, modified, limited, or
extinguished. The execution of this Guaranty shall not affect the validity or
enforceability of any existing guaranties, which guaranties shall remain in full
force and effect. All obligations hereunder shall continue, notwithstanding the
incapacity or lack of authority of the other guarantors, and any failure by the
Bank to file, pursue or enforce a claim against any of the other guarantors, or
any waiver, release, consent or other accommodation given or provided to any of
the other guarantors, shall not operate to release the Guarantor or other
guarantors from liability hereunder, or limit the rights of the Bank against the
Guarantor or any other guarantor. The failure of any other person to sign this
Guaranty or any other guaranty shall not release or affect the liability of the
signer hereof. The Loan Documents have been submitted to the Guarantor for
examination, and the Guarantor acknowledges that, by execution of this Guaranty,
it has approved the Loan Documents.

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         This writing is intended by the parties hereto as a final expression of
this Guaranty and is also intended as a complete and exclusive statement of the
terms of that agreement. No course of dealing, course of performance or trade
usage, and no parole evidence of any nature, shall be used to supplement or
modify any terms hereof.

         The Guarantor further agrees that, to the extent that the Borrower
makes a payment or payments to the Bank, or the Bank receives any proceeds of
collateral, which payment or payments or any part thereof are subsequently
invalidated, declared to be fraudulent or preferential, set aside or otherwise
is required to be repaid to the Borrower, its estate, trustee, receiver or any
other party, including, without limitation, under any bankruptcy law, state or
federal law, common law or equitable cause, then to the extent of such payment
or repayment, the Liabilities or part thereof which has been paid, reduced or
satisfied by such amount shall be reinstated and continued in full force and
effect as of the date such initial payment, reduction or satisfaction occurred.
The Guarantor shall defend and indemnify the Bank from any claim or loss under
this paragraph including the Bank's attorney's and paralegal's fees and expenses
and other expenses in the defense of any such action or suit.

         The Guarantor agrees that the Guarantor's responsibility under this
Guaranty to pay to the Bank the Liabilities and any payments thereof repaid as
preferences shall not be extinguished or modified by any release of the Borrower
or other party primarily liable on the Liabilities, whether by voluntary
release, settlement of a bankruptcy proceeding, settlement of the contested
matter in a bankruptcy, settlement of litigation, settlement of a claim not yet
resulting in litigation, settlement of a preference claim or otherwise. In all
events the responsibility of the Guarantor to pay the Bank and the Bank's right
to recover from the Guarantor the full amount of the Liabilities shall extend
until Bank has received actual payment in full in cash of and performance of all
of the Liabilities, without regard to any modification or a release thereof, and
shall continue until such payment, by the passage of time and the Statute of
Limitations, cannot be recovered by the Borrower, the Borrower as debtor in
possession, a trustee in bankruptcy of the Borrower or any other person or
organization.

         This Guaranty shall extend to and bind the successors and assigns of
the Guarantor. This Guaranty shall inure to the benefit of all affiliates,
transferees, assignees and/or endorsees of the Bank of any part or parts or all
of the Liabilities and of the Bank's successors and assigns.

         THE VALIDITY OF THIS GUARANTY, ITS CONSTRUCTION, INTERPRETATION AND
ENFORCEMENT AND THE RIGHTS OF THE PARTIES HERETO SHALL BE DETERMINED UNDER,
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF
INDIANA, WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW. GUARANTOR AGREES THAT
ALL ACTIONS OR PROCEEDINGS ARISING IN CONNECTION WITH THIS GUARANTY SHALL BE
TRIED AND LITIGATED ONLY IN THE STATE COURTS LOCATED IN THE COUNTY OF MARION,
STATE OF INDIANA, OR THE FEDERAL COURTS WHOSE VENUE INCLUDES THE COUNTY OF
MARION, STATE OF INDIANA, OR, AT THE SOLE OPTION OF Bank, IN ANY OTHER COURT IN
WHICH Bank SHALL INITIATE LEGAL OR EQUITABLE PROCEEDINGS AND

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WHICH HAS SUBJECT MATTER JURISDICTION OVER THE MATTER IN CONTROVERSY. GUARANTOR
WAIVES, TO THE EXTENT PERMITTED UNDER APPLICABLE LAW, THE RIGHT TO A TRIAL BY
JURY AND ANY RIGHT GUARANTOR MAY HAVE TO ASSERT THE DOCTRINE OF "FORUM NON
CONVENIENS" OR TO OBJECT TO VENUE TO THE EXTENT ANY PROCEEDING IS BROUGHT IN
ACCORDANCE WITH THIS PARAGRAPH.

         IN WITNESS WHEREOF, the undersigned, as the authorized officer of the
Guarantor, has executed this Unconditional Unlimited Continuing Guaranty
effective as of this 13th day of May, 1997.

                                            COHESANT TECHNOLOGIES INC.

                                            ("Guarantor")

                                            By: /s/ Dwight D. Goodman
                                               --------------------------

                                            Printed:  Dwight D. Goodman
                                                    ---------------------

                                            Title:  President
                                                   ----------------------

                                            ACCEPTED:

                                            NBD BANK, N.A.
                                            ("Bank")

                                            By: /s/ Edward R. Salm
                                               --------------------------------
                                               Edward R. Salm, Vice President



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