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                                                                   EXHIBIT 10.19


                 SECOND AMENDMENT TO CREDIT AGREEMENT AND NOTE

THIS SECOND AMENDMENT TO CREDIT AGREEMENT AND NOTE (this "AMENDMENT") dated
effective as of January 28, 1998 (the "EFFECTIVE DATE"), is by and between DTM
CORPORATION ("BORROWER") and CHASE BANK OF TEXAS, NATIONAL ASSOCIATION, a
national banking association whose principal office is located in Houston, Texas
("BANK," formerly known as Texas Commerce Bank National Association).

PRELIMINARY STATEMENT.  Bank and Borrower entered into a Credit Agreement (with
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Borrowing Base) dated as of August 6, 1997, as amended by the First Amendment to
Credit Agreement and Note dated October 1, 1997 ("First Amendment") (as amended,
"CREDIT AGREEMENT").  The "Agreement", as used in the Credit Agreement, shall
also refer to the Credit Agreement as amended by this Amendment.  All
capitalized terms defined in the Credit Agreement and not otherwise defined
herein shall have the same meanings herein as in the Credit Agreement.

Borrower has executed and delivered payable to the order of Bank its Revolving
Promissory Note dated August 6, 1997, in the original principal amount of
$6,000,000.00 (but subject to a limitation as to availability of $2,000,000.00
under the terms of the First Amendment) as amended by the First Amendment (as
amended, "Note").  The "Note" as used in the Credit Agreement and the Note shall
refer to the Note as amended by this Amendment.

The B.F. Goodrich Company ("Guarantor") has executed and delivered its guaranty
dated October 1, 1997 ("Guaranty") guaranteeing Borrower's obligations as
defined and subject to the limitations, terms and conditions set out therein.

The parties now desire to extend the stated Termination Date of the revolving
Commitment and the stated maturity date of the Note each to April 1, 1999, and
make certain other modifications to the Credit Agreement as set out herein.

NOW THEREFORE, in consideration of the premises and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties agree as follows:

1.  Section 1.1 of the Credit Agreement is amended by substituting "April 1,
1999" for "June 1, 1998," wherever the latter appears (indicating the stated
Termination Date).

2. The first paragraph of the Note is amended by substituting "April 1, 1999"
for "June 1, 1998," where the latter appears (indicating the stated maturity
date of such Note).

3.  In consideration of the extension of maturity provided for in this
Amendment, Borrower agrees to pay a one-time, nonrefundable fee of $7,500.00,
due and payable in full upon execution of this Amendment.

4.  Borrower further acknowledges that each of the other Loan Documents is in
all other respects ratified and confirmed, and all of the rights, powers and
privileges created thereby or thereunder are ratified, extended, carried forward
and remain in full force and effect except as the Credit Agreement and the Note
are amended by this Amendment.

5.  WAIVER AGREEMENT: Bank has agreed to waive Borrower's compliance with the
following specific requirements as described and limited below for the period
from the Effective Date of the Second Amendment to April 1, 1999:


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(A)  The requirements in 2.1(b)(2) to submit a Borrowing Base Report with a
     Request for a Loan; and submit a Borrowing Base Report on a monthly or
     weekly basis; and that accounts receivable agings and listings and accounts
     payable agings be submitted, all as required by the Borrowing Base Report,
     Exhibit C and section 4.3;
(B)  The requirement in 2.1(e) that the asset audit by Bank be found acceptable
     to the Bank in is sole judgment;
(C)  The representation in 3.2 regarding material adverse change and change in
     the condition, financial or otherwise, of the Borrower and its Consolidated
     Subsidiaries;
(D)  The representation in Section 3.4 that neither Borrower nor any Subsidiary
     of Borrower is in default in the payment of any other material agreement to
     which it is party;
(E)  The requirement to comply with the lockbox requirements and to provide
     notice to account debtors of the Lockbox contained in 4.9 & 4.10 and 5.9;
(F)  The restriction on additional indebtedness and liens in section 5.1 & 5.2
(G)  Compliance with the financial covenants required by 5.3 as described in
     Exhibit C B. 1, 2, & 3 (Tangible Net Worth; Quick Ratio and EBITDA); and
(H)  The Events of Default described in 6.1(b) (c) &(d) but only as they relate
     to Borrower as Obligor; and as to (c) and (d), only as to the covenants
     that have been waived for purposes of  6.1(d).

The waivers contained herein do not constitute a waiver of any other defaults
not described in this Amendment that may currently exist or that may hereafter
occur.  Bank's delay in exercising any of its rights under the Credit Agreement
does not constitute a waiver of any rights or interests of Bank except as
specifically agreed to in writing by Bank.  This Section is not a general waiver
of the above-referenced covenants, or the Events of Default or any other
requirements contained in the Agreement or any other Loan Document.  Bank has
the right to refuse to make a Loan at any time that Borrower is not in
compliance with the terms of the Agreement as amended by this Amendment  If Bank
elects to make any Loans to Borrower while Borrower is out of compliance with
the Agreement or during the existence of an Event of Default, the making of the
Loan shall not constitute a waiver of any defaults then existing or thereafter
arising under the Agreement, and will not constitute the agreement of Bank to
make further Loans.  This Section constitutes the only evidence of Bank's waiver
of compliance with the above cited Sections of the Credit Agreement and then
only for the period described in this Amendment.

6.  This Amendment shall be included within the definition of "Loan Documents"
as used in this Agreement.

7.  This Amendment may be executed in any number of counterparts and by
different parties hereto in separate counterparts, each when so executed shall
be deemed an original and all of which taken together shall constitute but one
and the same agreement.

8.  THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS OF THE STATE OF TEXAS AND AS APPLICABLE, THE LAWS OF THE UNITED STATES OF
AMERICA.

THIS WRITTEN AMENDMENT AND THE OTHER LOAN DOCUMENTS CONSTITUTE A "LOAN
AGREEMENT" AS DEFINED IN SECTION 26.02(a) OF THE TEXAS BUSINESS & COMMERCE CODE,
AND REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE
CONTRADICTED BY


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EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.
THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
effective as of its Effective Date.


BORROWER:  DTM CORPORATION                      BANK:  CHASE BANK OF TEXAS,
                                                           NATIONAL ASSOCIATION

By: /s/John S. Murchison, III____
Name:  John S. Murchison, III                   By: /s/ Donna Tanner Day
President & CEO                                 Name:   Donna Tanner-Day,
Address:  1611 Headway Circle                           Vice President
               Building 2                       Address: P. O. Box 550,
               Austin, Texas 78754                       Austin, Texas 78789