<PAGE>

                                                                     Exhibit 4.2

             One Ashburton Place, Boston, Massachusetts 02108-1512

                             ARTICLES OF AMENDMENT
                   (General Laws, Chapter 156B, Section 72)

    We,    John A. Pino                                                    , *
       --------------------------------------------------------------------
    President

    and    Jeffery B. Lavin                                            , *Clerk
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    of    ACT Manufacturing, Inc.                                            ,
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                          (Exact name of corporation)

    located at:     2 Cabot Road, Hudson,  MA 01749                          ,
                -------------------------------------------------------------
               (Street address of corporation in Massachusetts)

    certify that these Articles of Amendment affecting articles numbered:

                3
    ---------------------------------------------------------------------------
         (Number those articles 1, 2, 3, 4, 5, and/or 6 being amended)

    of the Articles of Organization were duly adopted at a meeting held on July
29, 1999, by vote of:

7,821,702 shares of Common Stock, $.01 par value of 9,091,600
                    ----------------------------    ---------
                    (type, class & series, if any)
shares outstanding,

_____________________ shares of _____________________ of _______________ shares
outstanding, and
                                (type, class & series, if any)

_____________________ shares of _____________________ of ______________ shares
outstanding.
                                (type, class & series, if any)



1**being at least a majority of each type, class or series outstanding and
   entitled to vote thereon



*Delete the inapplicable words.               ** Delete the inapplicable clause.
/1/For amendments adopted pursuant to Chapter 156B, Section 70.
/2/For amendments adopted pursuant to Chapter 156B, Section 71.
Note: If the space provided under any article or item on this form is
insufficient, additions shall be set forth on one side only of separate 8 1/2 x
11 sheets of paper with a left margin of at least 1 inch. Additions to more than
one article may be made on a single sheet so long as each article requiring each
addition is clearly indicated.
<PAGE>

To change the number of shares and the par value (if any) of any type, class or
series of stock which the corporation is authorized to issue, fill in the
following:

The total presently authorized is:

<TABLE>
<CAPTION>
--------------------------------------------------- ----------------------------------------------------------------------
             WITHOUT PAR VALUE STOCKS                                       WITH PAR VALUE STOCKS
--------------------------------------------------- ----------------------------------------------------------------------
      TYPE                NUMBER OF SHARES               TYPE               NUMBER OF SHARES               PAR VALUE
------------------ -------------------------------- --------------- ---------------------------------- -------------------
<S>                <C>                              <C>             <C>                                <C>
Common:                           0                 Common:         30,000,000                                $.01
------------------ -------------------------------- --------------- ---------------------------------- -------------------

------------------ -------------------------------- --------------- ---------------------------------- -------------------
Preferred:                        0                 Preferred:      5,000,000                                 $.01
------------------ -------------------------------- --------------- ---------------------------------- -------------------

------------------ -------------------------------- --------------- ---------------------------------- -------------------

<CAPTION>
Change the total authorized to:

-------------------------------------------------- -----------------------------------------------------------------------
            WITHOUT PAR VALUE STOCKS                                       WITH PAR VALUE STOCKS
----------------- -------------------------------- --------------- --------------------------------- ---------------------
      TYPE               NUMBER OF SHARES               TYPE               NUMBER OF SHARES               PAR VALUE
----------------- -------------------------------- --------------- --------------------------------- ---------------------
<S>                <C>                              <C>             <C>                                <C>
Common:                          0                 Common:         50,000,000                                $.01
----------------- -------------------------------- --------------- --------------------------------- ---------------------

----------------- -------------------------------- --------------- --------------------------------- ---------------------
Preferred:                       0                 Preferred:      5,000,000                                 $.01
----------------- -------------------------------- --------------- --------------------------------- ---------------------

----------------- -------------------------------- --------------- --------------------------------- ---------------------
</TABLE>
<PAGE>

The foregoing amendment(s) will become effective when these Articles of
Amendment are filed in accordance with General Laws, Chapter 156B, Section 6
unless these articles specify, in accordance with the vote adopting the
amendment, a later effective date not more than thirty days after such filing,
in which event the amendment will become effective on such later date.

Later effective date:  ___________________________________



SIGNED UNDER THE PENALTIES OF PERJURY, this 29th day of July, 1999.

/s/ John A. Pino                                                    , *President
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/s/ Jeffrey B. Lavin                                                , *Clerk
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*Delete the inapplicable words.
<PAGE>

                       THE COMMONWEALTH OF MASSACHUSETTS


                             ARTICLES OF AMENDMENT

                   (General Laws, Chapter 156B, Section 72)

          _______________________________________________________________

                  I hereby approve the within Articles of Amendment,
                  and the filing fee in the amount of $20,000 having
                  been paid, said article is deemed to have been filed
                  with me this 29/th/ day of July, 1999.
                                                     --

                  Effective date:
                                  July 29, 1999
                  -------------------------------------------






                          /s/ William Francis Galvin

                            WILLIAM FRANCIS GALVIN

                         Secretary of the Commonwealth






                        TO BE FILLED IN BY CORPORATION

                     Photocopy of document to be sent to:



                        Kelly R. Whiting, Esq.
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                        Testa, Hurwitz & Thibeault, LLP
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                        High Street Tower
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                        125 High Street
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                        Boston, MA  02110
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