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                                                                     EXHIBIT 5.1

                                September 3, 1998

Simonds Industries, Inc.
135 Intervale Road
Fitchburg, MA 01420

Ladies and Gentlemen:

We have acted as counsel to Simonds Industries, Inc., a Delaware corporation
(the "Company"), and to its subsidiaries, Armstrong Manufacturing Company,
Simonds Holding Company, Inc., and Simonds Industries FSC, Inc. (collectively,
the "Guarantors") in connection with a Registration Statement on Form S-4 (the
"Registration Statement") to be filed by the Company and the Guarantors with the
Securities and Exchange Commission relating to (i) the proposed issuance by the
Company of up to $100,000,000 aggregate principal amount of its new 10-1/4%
Senior Subordinated Notes due 2008 registered under the Securities Act of 1933,
as amended (the "Exchange Notes"), in exchange for a like principal amount of
the Company's outstanding 10-1/4% Senior Subordinated Notes due 2008, which have
not been so registered (the "Original Notes") (the "Exchange Offer"), and (ii)
the guarantees of the Exchange Notes by the Guarantors (the "Guarantees"). The
Exchange Notes will be issued under an Indenture dated as of July 7, 1998 (the
"Indenture") among the Company, the Guarantors and State Street Bank and Trust
Company, as trustee.

We have examined and relied upon the information set forth in the Registration
Statement and such other documents and records as we have deemed necessary. In
addition, as to questions of fact material to our opinion, we have relied upon
certificates of officers of the Company and the Guarantors and public officials.

In the course of our examination, we have assumed the legal capacity of all
natural persons, the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such latter documents. In making our
examination of documents executed by parties other than the Company and the
Guarantors, we have assumed that such parties had the power to enter into and
perform all obligations thereunder and have also assumed the due authorization
by all requisite action, and execution and delivery by such parties of such
documents and the validity and binding effect thereof on such parties.

We express no opinion as to the laws of any jurisdiction other than those of The
Commonwealth of Massachusetts, the General Corporation Law of the State of
Delaware and the federal laws of the United States of America. We call your
attention to the fact that each of the Indenture, the Exchange Notes and the
Guarantees provides that it is to be governed by the internal laws of the State
of New York. We are of the opinion that a Massachusetts court or a federal court
sitting in Massachusetts would, under conflict of 

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law principles observed by the courts of Massachusetts, give effect to such
provisions. For purposes of the opinion provided herein, we have assumed with
your permission that the Indenture, the Exchange Notes and the Guarantees
provide that they are to be governed by and construed in accordance with the
domestic substantive laws of The Commonwealth of Massachusetts.

Based upon the foregoing, we are of the opinion that the Exchange Notes and the
Guarantees have been duly authorized by all requisite corporate action of the
Company and the Guarantors, as the case may be, and, when executed and
authenticated in the manner provided for in the Indenture and delivered against
surrender and cancellation of a like aggregate principal amount of Original
Notes as contemplated in the Registration Rights Agreement, dated July 7, 1998,
among the Company, the Guarantors and the Initial Purchasers named therein, the
Exchange Notes will constitute valid and binding obligations of the Company and
the Guarantors, as the case may be, entitled to the benefits of the Indenture
and enforceable against the Company and the Guarantors, as the case may be, in
accordance with their terms, except as enforcement thereof may be limited by
bankruptcy, insolvency, reorganization, moratorium or other laws relating to or
affecting creditors' rights generally or by general equitable principles
(regardless of whether considered in a proceeding in equity or at law).

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption "Legal
Matters" contained in the Prospectus included therein.



                                     Very truly yours,

                                     /s/ Wellesley Law Associates




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