<PAGE>   1

   AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON SEPTEMBER 5, 1997
                                                  REGISTRATION NO. 333-_________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                             ----------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                             ----------------------
                                ELECTROGLAS, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

           DELAWARE                                         77-0336101
(State or Other Jurisdiction of                          (I.R.S. Employer
Incorporation or Organization)                        Identification Number)

                               2901 CORONADO DRIVE
                          SANTA CLARA, CALIFORNIA 95054
                                 (408) 727-6500
               (Address, Including Zip Code, and Telephone Number,
                      Including Area Code, of Registrant's
                          Principal Executive Offices)
   1997 STOCK INCENTIVE PLAN AND STOCK OPTIONS GRANTED PURSUANT TO AGREEMENTS
             MADE BETWEEN ELECTROGLAS, INC. AND CERTAIN EMPLOYEES OF
                            KNIGHTS TECHNOLOGY, INC.
                         -------------------------------
                              (Full Title of Plans)
                                ARMAND J. STEGALL
    VICE PRESIDENT-FINANCE, CHIEF FINANCIAL OFFICER, TREASURER AND SECRETARY
                                ELECTROGLAS, INC.
                               2901 CORONADO DRIVE
                          SANTA CLARA, CALIFORNIA 95054
                                 (408) 727-6500
            (Name, Address, Including Zip Code, and Telephone Number,
                        Including Area Code, of Agent for
                                    Service)
                                 ---------------
                                   Copies to:
                             STEPHEN M. TENNIS, ESQ.
                               CORI M. ALLEN, ESQ.
                             MORRISON & FOERSTER LLP
                               755 PAGE MILL ROAD
                            PALO ALTO, CA 94304-1018
                                 (415) 813-5600
                                 ---------------

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
                                                 MAXIMUM      PROPOSED MAXIMUM    AMOUNT OF
    TITLE OF SECURITIES        AMOUNT TO     OFFERING PRICE  AGGREGATE OFFERING  REGISTRATION
     TO BE REGISTERED        BE REGISTERED    PER SHARE(1)        PRICE(1)           FEE
    -------------------      -------------   --------------  ------------------  ------------
<S>                          <C>             <C>             <C>                 <C>      
 Common Stock, $.001
 par value per share.....       806,250           $32.00       $25,800,000.00       $7,818.00
</TABLE>


(1) Estimated solely for the purpose of calculating the amount of the
    registration fee in accordance with Rule 457(c) and Rule 457(h) of
    Regulation C promulgated under the Securities Act of 1933, as amended (the
    "Securities Act").


                               Page 1 of 7 pages
                   The Index to Exhibits appears on page II-4


<PAGE>   2


                                     PART I

                           INFORMATION REQUIRED IN THE
                            SECTION 10(a) PROSPECTUS


        The documents containing the information specified in Part 1 of Form S-8
(plan information and registrant information and employee plan annual
information) will be sent or given to employees as specified by Securities and
Exchange Commission Rule 428(b)(1). Such documents need not be filed with the
Securities and Exchange Commission either as part of this Registration Statement
or as prospectuses or prospectus supplements pursuant to Rule 424. These
documents and the documents incorporated by reference in this Registration
Statement pursuant to Item 3 of Form S-8 (Part II hereof), taken together,
constitute a prospectus that meets the requirements of Section 10(a) of the
Securities Act of 1933.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

        In accordance with General Instruction E to Form S-8, the contents of
the Registrant's Registration Statement on Form S-8, Commission File No.
333-28327, including exhibits thereto, are hereby incorporated by reference into
this Registration Statement, except as the same may be modified by the
information set forth herein.

ITEM 8.  EXHIBITS.

        4.1    Certificate of Incorporation of the Registrant, as amended
               (incorporated by reference to Exhibit 3.1 to the Registrant's
               Registration Statement on Form S-1 (Commission File No. 33-61523)
               which became effective on June 23, 1993 (the "1993 Registration
               Statement")).

        4.2    Bylaws of the Registrant (incorporated by reference to Exhibit
               3.2 to the 1993 Registration Statement).

        5.1    Opinion of Morrison & Foerster LLP

        23.1   Opinion of Morrison & Foerster LLP (contained in Exhibit 5.1)

        23.2   Consent of Ernst & Young LLP, Independent Auditors 
               (see Page II-6)

        24.1   Power of Attorney (See Page II-2)


                                Page 2 of 7 pages
                                      II-1


<PAGE>   3




        SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the
Registrant, Electroglas, Inc., certifies that it has reasonable grounds to
believe that it meets all of the requirements for filing on Form S-8 and has
duly caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of San Jose, State of
California, on September 5, 1997.

                                          ELECTROGLAS, INC


                                          By:  /s/ Curtis S. Wozniak
                                             -----------------------------------
                                            Curtis S. Wozniak
                                            Chief Executive Officer

                                POWER OF ATTORNEY

       Each person whose signature appears below constitutes and appoints Curtis
S. Wozniak and Armand J. Stegall, and each of them, as attorneys-in-fact, each
with the power of substitution, for him in any and all capacities, to sign any
amendment to this Registration Statement and to file the same, with exhibits
thereto and other documents in connection therewith, with the Securities and
Exchange Commission, granting to said attorneys-in-fact, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in connection therewith, as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming the said
attorney-in-fact or his substitute or substitutes, may lawfully do or cause to
be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the date indicated.


<TABLE>
<CAPTION>
Signature                             Capacity                 Date
- ---------                             --------                 ----

<S>                               <C>                      <C>
 /s/ Curtis S. Wozniak            Chief Executive          September 5, 1997
- -------------------------         Officer and Director
     Curtis S. Wozniak            and Chairman
                                  (Principal Executive
                                  Officer)
                                  
</TABLE>


                                Page 3 of 7 pages
                                      II-2


<PAGE>   4


<TABLE>
<CAPTION>
Signature                             Capacity                 Date
- ---------                             --------                 ----
<S>                               <C>                      <C>
 /s/ Armand J. Stegall            Vice President,          September 5, 1997
- -------------------------         Finance, Chief
     Armand J. Stegall            Financial Officer,
                                  Treasurer and
                                  Secretary (Principal
                                  Financial and
                                  Accounting Officer)

  /s/ Neil R. Bonke               Director                 September 5, 1997
- -------------------------
      Neil R. Bonke

 /s/ Joseph F. Dox                Director                 September 5, 1997
- -------------------------
     Joseph F. Dox

 /s/ Roger D. Emerick             Director                 September 5, 1997
- -------------------------
     Roger D. Emerick

 /s/ Robert J. Frankenberg        Director                 September 5, 1997
- -------------------------
     Robert J. Frankenberg
</TABLE>


                                Page 4 of 7 pages
                                      II-3


<PAGE>   5


                                INDEX TO EXHIBITS


<TABLE>
<CAPTION>
EXHIBIT                                                                            SEQUENTIALLY
NUMBER                       DOCUMENT                                              NUMBERED PAGES
- -------                      --------                                              --------------

<S>            <C>                                                                  <C>
  4.1          Certificate of Incorporation of the Registrant, as amended
               (incorporated by reference to Exhibit 3.1 to the Registrant's
               Registration Statement on Form S-1 (Commission File No. 33-61523)
               which became effective on June 23, 1993 (the "1993 Registration
               Statement")).

  4.2          Bylaws of the Registrant (incorporated by reference to
               Exhibit 3.2 to the 1993 Registration Statement).

   5.1         Opinion of Morrison & Foerster LLP

  23.1         Consent of Counsel (included in Exhibit 5.1)

  23.2         Consent of Ernst & Young LLP, Independent
               Auditors (see page II-6)

  24.1         Power of Attorney (see page II-2)
</TABLE>


                                Page 5 of 7 pages
                                      II-4


<PAGE>   6


                                                                     EXHIBIT 5.1

September 5, 1997

Electroglas, Inc.
2901 Coronado Drive
Santa Clara, California 95054

Ladies and Gentlemen:

               We have examined the Registration Statement on Form S-8 to be
filed by Electroglas, Inc., a Delaware corporation (the "Company"), with the
Securities and Exchange Commission on September 5, 1997 (the "Registration
Statement"), relating to the registration under the Securities Act of 1933, as
amended, of 806,250 shares of the Company's Common Stock (the "Shares"). The
Shares are reserved for issuance pursuant to the Company's 1997 Stock Incentive
Plan and an agreement with certain employees of Knights Technology, Inc. As
counsel to the Company, we have examined the proceedings taken by the Company in
connection with the registration of the Shares.

               It is our opinion that the Shares, when issued and sold in the
manner described in the Registration Statement and the related Prospectus, will
be legally and validly issued, fully paid and nonassessable.

               We consent to the use of this opinion as an exhibit to the
Registration Statement and further consent to all references to us in the
Registration Statement and any amendments thereto.

                                            Very truly yours,


                                            /s/ Morrison & Foerster LLP


                                Page 6 of 7 pages
                                      II-5


<PAGE>   7


                                                                    EXHIBIT 23.2



                      CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS


        We consent to the incorporation by reference in the Registration
Statement (Form S-8) pertaining to the 1997 Stock Incentive Plan and Stock
Options granted pursuant to Agreements made between Electroglas, Inc. and
Certain Employees of Knights Technology, Inc. of our reports dated January 21,
1997 (except for Note 11, as to which the date is March 12, 1997), with respect
to the consolidated financial statements of Electroglas, Inc. incorporated by
reference in its Annual Report on Form 10-K for the year ended December 31, 1996
and the related financial statement schedule included therein, filed with the
Securities and Exchange Commission.

                                            /s/ Ernst & Young LLP


San Jose, California
September 4, 1997


                                Page 7 of 7 pages
                                      II-6
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 13356}]
{"company-data": {"conformed-name": "ELECTROGLAS INC", "cik": "0000902281", "assigned-sic": "3559", "irs-number": "770336101", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "file-number": "333-35023", "film-number": "97676011"}, "business-address": {"street1": "2901 CORONADO DRIVE", "city": "SANTA CLARA", "state": "CA", "zip": "95054", "phone": "4087276500"}, "mail-address": {"street1": "2901 CORONADO DRIVE", "city": "SASSANTA CL", "state": "CA", "zip": "95054"}}
1

   AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON SEPTEMBER 5, 1997
                                                  REGISTRATION NO. 333-_________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                             ----------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                             ----------------------
                                ELECTROGLAS, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

           DELAWARE                                         77-0336101
(State or Other Jurisdiction of                          (I.R.S. Employer
Incorporation or Organization)                        Identification Number)

                               2901 CORONADO DRIVE
                          SANTA CLARA, CALIFORNIA 95054
                                 (408) 727-6500
               (Address, Including Zip Code, and Telephone Number,
                      Including Area Code, of Registrant's
                          Principal Executive Offices)
   1997 STOCK INCENTIVE PLAN AND STOCK OPTIONS GRANTED PURSUANT TO AGREEMENTS
             MADE BETWEEN ELECTROGLAS, INC. AND CERTAIN EMPLOYEES OF
                            KNIGHTS TECHNOLOGY, INC.
                         -------------------------------
                              (Full Title of Plans)
                                ARMAND J. STEGALL
    VICE PRESIDENT-FINANCE, CHIEF FINANCIAL OFFICER, TREASURER AND SECRETARY
                                ELECTROGLAS, INC.
                               2901 CORONADO DRIVE
                          SANTA CLARA, CALIFORNIA 95054
                                 (408) 727-6500
            (Name, Address, Including Zip Code, and Telephone Number,
                        Including Area Code, of Agent for
                                    Service)
                                 ---------------
                                   Copies to:
                             STEPHEN M. TENNIS, ESQ.
                               CORI M. ALLEN, ESQ.
                             MORRISON & FOERSTER LLP
                               755 PAGE MILL ROAD
                            PALO ALTO, CA 94304-1018
                                 (415) 813-5600
                                 ---------------

                         CALCULATION OF REGISTRATION FEE
MAXIMUM      PROPOSED MAXIMUM    AMOUNT OF
    TITLE OF SECURITIES        AMOUNT TO     OFFERING PRICE  AGGREGATE OFFERING  REGISTRATION
     TO BE REGISTERED        BE REGISTERED    PER SHARE(1)        PRICE(1)           FEE
    -------------------      -------------   --------------  ------------------  ------------
Common Stock, $.001
 par value per share.....       806,250           $32.00       $25,800,000.00       $7,818.00
(1) Estimated solely for the purpose of calculating the amount of the
    registration fee in accordance with Rule 457(c) and Rule 457(h) of
    Regulation C promulgated under the Securities Act of 1933, as amended (the
    "Securities Act").

                               Page 1 of 7 pages
                   The Index to Exhibits appears on page II-4
2

                                     PART I

                           INFORMATION REQUIRED IN THE
                            SECTION 10(a) PROSPECTUS

        The documents containing the information specified in Part 1 of Form S-8
(plan information and registrant information and employee plan annual
information) will be sent or given to employees as specified by Securities and
Exchange Commission Rule 428(b)(1). Such documents need not be filed with the
Securities and Exchange Commission either as part of this Registration Statement
or as prospectuses or prospectus supplements pursuant to Rule 424. These
documents and the documents incorporated by reference in this Registration
Statement pursuant to Item 3 of Form S-8 (Part II hereof), taken together,
constitute a prospectus that meets the requirements of Section 10(a) of the
Securities Act of 1933.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

        In accordance with General Instruction E to Form S-8, the contents of
the Registrant's Registration Statement on Form S-8, Commission File No.
333-28327, including exhibits thereto, are hereby incorporated by reference into
this Registration Statement, except as the same may be modified by the
information set forth herein.

ITEM 8.  EXHIBITS.

        4.1    Certificate of Incorporation of the Registrant, as amended
               (incorporated by reference to Exhibit 3.1 to the Registrant's
               Registration Statement on Form S-1 (Commission File No. 33-61523)
               which became effective on June 23, 1993 (the "1993 Registration
               Statement")).

        4.2    Bylaws of the Registrant (incorporated by reference to Exhibit
               3.2 to the 1993 Registration Statement).

        5.1    Opinion of Morrison & Foerster LLP

        23.1   Opinion of Morrison & Foerster LLP (contained in Exhibit 5.1)

        23.2   Consent of Ernst & Young LLP, Independent Auditors 
               (see Page II-6)

        24.1   Power of Attorney (See Page II-2)

                                Page 2 of 7 pages
                                      II-1
3

        SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the
Registrant, Electroglas, Inc., certifies that it has reasonable grounds to
believe that it meets all of the requirements for filing on Form S-8 and has
duly caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of San Jose, State of
California, on September 5, 1997.

                                          ELECTROGLAS, INC

                                          By:  /s/ Curtis S. Wozniak
                                             -----------------------------------
                                            Curtis S. Wozniak
                                            Chief Executive Officer

                                POWER OF ATTORNEY

       Each person whose signature appears below constitutes and appoints Curtis
S. Wozniak and Armand J. Stegall, and each of them, as attorneys-in-fact, each
with the power of substitution, for him in any and all capacities, to sign any
amendment to this Registration Statement and to file the same, with exhibits
thereto and other documents in connection therewith, with the Securities and
Exchange Commission, granting to said attorneys-in-fact, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in connection therewith, as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming the said
attorney-in-fact or his substitute or substitutes, may lawfully do or cause to
be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the date indicated.
Signature                             Capacity                 Date
- ---------                             --------                 ----
/s/ Curtis S. Wozniak            Chief Executive          September 5, 1997
- -------------------------         Officer and Director
     Curtis S. Wozniak            and Chairman
                                  (Principal Executive
                                  Officer)
Page 3 of 7 pages
                                      II-2
4
Signature                             Capacity                 Date
- ---------                             --------                 ----
/s/ Armand J. Stegall            Vice President,          September 5, 1997
- -------------------------         Finance, Chief
     Armand J. Stegall            Financial Officer,
                                  Treasurer and
                                  Secretary (Principal
                                  Financial and
                                  Accounting Officer)

  /s/ Neil R. Bonke               Director                 September 5, 1997
- -------------------------
      Neil R. Bonke

 /s/ Joseph F. Dox                Director                 September 5, 1997
- -------------------------
     Joseph F. Dox

 /s/ Roger D. Emerick             Director                 September 5, 1997
- -------------------------
     Roger D. Emerick

 /s/ Robert J. Frankenberg        Director                 September 5, 1997
- -------------------------
     Robert J. Frankenberg
Page 4 of 7 pages
                                      II-3
5

                                INDEX TO EXHIBITS
EXHIBIT                                                                            SEQUENTIALLY
NUMBER                       DOCUMENT                                              NUMBERED PAGES
- -------                      --------                                              --------------
4.1          Certificate of Incorporation of the Registrant, as amended
               (incorporated by reference to Exhibit 3.1 to the Registrant's
               Registration Statement on Form S-1 (Commission File No. 33-61523)
               which became effective on June 23, 1993 (the "1993 Registration
               Statement")).

  4.2          Bylaws of the Registrant (incorporated by reference to
               Exhibit 3.2 to the 1993 Registration Statement).

   5.1         Opinion of Morrison & Foerster LLP

  23.1         Consent of Counsel (included in Exhibit 5.1)

  23.2         Consent of Ernst & Young LLP, Independent
               Auditors (see page II-6)

  24.1         Power of Attorney (see page II-2)
Page 5 of 7 pages
                                      II-4
6

                                                                     EXHIBIT 5.1

September 5, 1997

Electroglas, Inc.
2901 Coronado Drive
Santa Clara, California 95054

Ladies and Gentlemen:

               We have examined the Registration Statement on Form S-8 to be
filed by Electroglas, Inc., a Delaware corporation (the "Company"), with the
Securities and Exchange Commission on September 5, 1997 (the "Registration
Statement"), relating to the registration under the Securities Act of 1933, as
amended, of 806,250 shares of the Company's Common Stock (the "Shares"). The
Shares are reserved for issuance pursuant to the Company's 1997 Stock Incentive
Plan and an agreement with certain employees of Knights Technology, Inc. As
counsel to the Company, we have examined the proceedings taken by the Company in
connection with the registration of the Shares.

               It is our opinion that the Shares, when issued and sold in the
manner described in the Registration Statement and the related Prospectus, will
be legally and validly issued, fully paid and nonassessable.

               We consent to the use of this opinion as an exhibit to the
Registration Statement and further consent to all references to us in the
Registration Statement and any amendments thereto.

                                            Very truly yours,

                                            /s/ Morrison & Foerster LLP

                                Page 6 of 7 pages
                                      II-5
7

                                                                    EXHIBIT 23.2

                      CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

        We consent to the incorporation by reference in the Registration
Statement (Form S-8) pertaining to the 1997 Stock Incentive Plan and Stock
Options granted pursuant to Agreements made between Electroglas, Inc. and
Certain Employees of Knights Technology, Inc. of our reports dated January 21,
1997 (except for Note 11, as to which the date is March 12, 1997), with respect
to the consolidated financial statements of Electroglas, Inc. incorporated by
reference in its Annual Report on Form 10-K for the year ended December 31, 1996
and the related financial statement schedule included therein, filed with the
Securities and Exchange Commission.

                                            /s/ Ernst & Young LLP

San Jose, California
September 4, 1997

                                Page 7 of 7 pages
                                      II-6