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                                                                     EXHIBIT 5.1

                              Barrett & McNagny LLP
                              215 East Berry Street
                            Fort Wayne, Indiana 46802



September 19, 2002


Steel Dynamics, Inc.
6714 Pointe Inverness Way, Suite 200
Fort Wayne, Indiana   46804

Gentlemen:

We have acted as counsel to Steel Dynamics, Inc., an Indiana corporation (the
"Company"), in connection with the Registration Statement on Form S-4 (the
"Registration Statement") filed by the Company with the Securities and Exchange
Commission under the Securities Act of 1933, as amended (the "Securities Act"),
relating to the registration by the Company of $200,000,000 aggregate principal
amount of its 9 1/2% Senior Notes due 2009 (the "Exchange Notes"). The Exchange
Notes are proposed to be issued in accordance with the provisions of the
indenture (the "Indenture"), dated as of March 26, 2002, between the Company and
Fifth Third Bank as Trustee.

In connection with rendering the opinions set forth below, we have examined the
Registration Statement, the Prospectus contained therein, the Indenture, which
is filed as an exhibit to the Registration Statement, the Articles of
Incorporation and Bylaws of the Company and resolutions adopted by the Board of
Directors of the Company, and we have made such other investigation as we have
deemed appropriate. We have examined and relied on certificates of public
officials. We have not independently established any of the facts so relied on.

For purposes of this opinion letter we have made the assumptions that are
customary in opinion letters of this kind, including the assumptions that each
document submitted to us is accurate and complete, that each such document that
is an original is authentic, that each such document that is a copy conforms to
an authentic original, and that all signatures (other than signatures on behalf
of the Company) on each such document are genuine. We have further assumed the
legal capacity of natural persons, and we have assumed that each party to the
documents we have examined or relied on (other than the Company) has the legal
capacity or authority and has satisfied all legal requirements that are
applicable to that party to the extent necessary to make such documents
enforceable against that party. We have not verified any of these assumptions.

Based on the foregoing, and subject to the foregoing and the additional
qualifications and other matters set forth below, it is our opinion that the
Exchange Notes, when (a) the Company's outstanding 9 1/2% Notes Due 2009 have
been exchanged in the manner described in the Registration Statement, (b) the
Exchange Notes have been duly executed, authenticated, issued and delivered in
accordance with the terms of the Indenture, (c) the Indenture has been duly
qualified under the Trust Indenture Act of 1939, as amended, and (d) applicable
provisions of "blue sky" laws have been complied with, will constitute valid and
binding obligations of the Company enforceable against the Company in accordance
with their terms, under the laws of the State of New York which are expressed to
govern the same, except as the enforcement thereof may be limited by bankruptcy,
insolvency, reorganization, moratorium (including, without limitation, all laws
relating to fraudulent transfers), other similar laws relating to or affecting
enforcement of creditors' rights generally, general principles of equity
(regardless of whether enforcement is considered in a proceeding in equity or at
law) and limitations of the waiver of rights under usury laws, and will be
entitled to the benefits of the Indenture.

We express no opinion as to the validity, legally binding effect or
enforceability of any related provisions of the Indenture or the Exchange Notes
that require or relate to payment of any interest at a rate or in an amount
which a court would determine in the circumstances under applicable law to be
commercially unreasonable or a penalty or a forfeiture. In addition, we express
no opinion as to the validity, legally binding effect or enforceability of the
waiver of rights and defenses contained in the Indenture.
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We are furnishing this opinion letter to you solely in connection with the
registration under the Securities Act by the Company of the Exchange Notes. You
may not rely on this opinion letter in any other connection, and it may not be
furnished to or relied upon by any other person for any purpose, without our
specific prior written consent.

The foregoing opinions are rendered as of the date of this letter.

We hereby consent to the reference to us in the Registration Statement under the
caption "Legal Matters."

Very truly yours,

/s/ BARRETT & McNAGNY LLP

