Exhibit 5
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                     [LETTERHEAD OF MAYER, BROWN & PLATT]

                                March 17, 1998


Elgin National Industries, Inc.
2001 Butterfield Road, Suite 1020
Downers Grove, IL 60515

     Re:  $85 million 11% Senior Notes due 2007

Ladies and Gentlemen:

     We have acted as counsel to Elgin National Industries, Inc., a Delaware
corporation ("Elgin"), in connection with the registration under the Securities
Act of 1933, as amended (the "Act"), of an Exchange Offer (the "Exchange Offer")
relating to $85 million principal amount of 11% Series A Senior Notes due 2007
(the "Old Notes"). The Old Notes were issued under an Indenture between Elgin,
certain of its subsidiaries and Norwest Bank Minnesota, National Association, as
trustee. We have participated in the preparation and filing with the Securities
and Exchange Commission under the Act of a registration statement on Form S-4
(the "Registration Statement"), Registration No. 333-43523, relating to $85
million principal amount of 11% Series B Senior Notes due 2007 (the "New Notes")
with respect to the proposed Exchange Offer for the Old Notes. In this
connection, we have examined such corporate and other records, instruments,
certificates and documents as we have considered necessary to enable us to
render this opinion.

     Based on the foregoing, it is our opinion that, upon completion of the
Exchange Offer, the New Notes will have been duly authorized for issuance and,
when duly executed, authenticated, issued and delivered, will constitute valid
and legally binding obligations of Elgin, entitled to the benefits of the
Indenture, subject to bankruptcy, insolvency, reorganization, moratorium and
similar laws of general applicability relating to or affecting creditor's rights
and to general equitable principles (whether considered in a proceeding at law
or in equity).

     We consent to the filing of this opinion as an exhibit to the Registration
Statement and to the reference to us under the caption "Legal Matters."

                                        Very truly yours,

                                        /s/ Mayer, Brown & Platt

                                        MAYER, BROWN & PLATT