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                                                                    EXHIBIT 10.1

Silicon Valley Bank

Amendment to Loan Agreements

Borrower:     DTM Corporation
Address:      1611 Headway Circle, Building 2
              Austin, Texas 78754

Date:         June 8, 2001

     THIS AMENDMENT TO LOAN AGREEMENTS is entered into between Silicon Valley
Bank ("Silicon") and the borrower named above ("Borrower").

     Silicon and Borrower have entered into (i) a Loan and Security Agreement
dated June 8, 1999 (as amended, the "Domestic Loan Agreement"), and (ii) a Loan
and Security Agreement (Exim Program) dated June 8, 1999 (as amended, the "Exim
Loan Agreement"; the Domestic Loan Agreement and the Exim Loan Agreement may be
collectively referred to herein as the "Loan Agreements"), together with certain
documents, instruments and agreements related to the Loan Agreements.

     Silicon and Borrower agree to amend the Loan Agreements as follows,
effective as of the date hereof.  (Capitalized terms used but not defined in
this Amendment, shall have the meanings set forth in the Loan Agreements.)

     1.  Domestic Loan Agreement Credit Limit.  In Section 1 of the Schedule to
the Domestic Loan Agreement, all language preceding the heading entitled "Letter
of Credit Sublimit" is hereby amended to read as follows:

     "1.  Credit Limit
          (Section 1.1):  An amount not to exceed the lesser of a total of
                          $3,000,000 at any one time outstanding (the "Maximum
                          Credit Limit"), or the sum or (a) and (b) below:

                          (a)  85% of the amount of Borrower's Eligible
                               Receivables (as defined in Section 8 above), plus

                          (b)  an amount not to exceed the lesser of:

                               (1)  40% of the value of Borrower's Eligible
                                    Inventory (as defined in Section 8 above),
                                    calculated at the lower of cost or market
                                    value

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                                    and determined on a first-in, first-out
                                    basis;

                                    or

                               (2)  $500,000."

     2.  Domestic Loan Agreement Interest Rate.  Section 2 of the Schedule to
the Domestic Loan Agreement is hereby amended in its entirety to read as
follows:

     "2.  Interest.
       Interest Rate

       (Section 1.2):  A rate equal to the "Prime Rate" in effect from time to
                       time, plus 1.25% per annum.  Interest shall be calculated
                       on the basis of a 360-day year for the actual number of
                       days elapsed.  "Prime Rate" means the rate announced from
                       time to time by Silicon as its "prime rate;" it is a base
                       rate upon which other rates charged by Silicon are based,
                       and it is not necessarily the best rate available at
                       Silicon.  The interest rate applicable to the Obligations
                       shall change on each date there is a change in the Prime
                       Rate.

       Minimum Monthly
       Interest (Section 1.2):  N/A."
     3.  Domestic Loan Agreement Maturity Date.  Section 4 of the Schedule to
the Domestic Loan Agreement is hereby amended in its entirety to read as
follows:

     "4.  Maturity Date
         (Section 6.1):   June 8, 2002."

     4.  Domestic Loan Agreement Audit Fees.  In the third sentence of Section
5.4 of the Domestic Loan Agreement, the amount "$600" is hereby replaced by the
amount "$700", so that such sentence now reads as follows:

     "The foregoing inspections and audits shall be at Borrower's expense and
     the charge therefor shall be $700 per person per day (or such higher amount
     as shall represent Silicon's then current standard charge for the same),
     plus reasonable out of pocket expenses."

     5.  Domestic Loan Agreement Early Termination Fee.  Section 6.2 of the
Domestic Loan Agreement is hereby amended in its entirety to read as follows:

          "6.2  Early Termination.  This Agreement may be terminated prior to
     the Maturity Date as follows:  (i) by Borrower, effective three Business
     Days after written notice of termination is given to Silicon; or (ii) by
     Silicon at any time after the occurrence of an Event of Default, without
     notice, effective immediately.  If this Agreement is terminated by

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     Borrower or by Silicon under this Section 6.2, Borrower shall pay to
     Silicon a termination fee in an amount equal to * two percent (2.0%) of the
     Maximum Credit Limit, provided that no termination fee shall be charged if
     the credit facility hereunder is replaced with a new facility from another
     division of Silicon Valley Bank**. The termination fee shall be due and
     payable on the effective date of termination and thereafter shall bear
     interest at a rate equal to the highest rate applicable to any of the
     Obligations.

     * one percent (1.0%)

     ** or is paid from the proceeds of a merger between Borrower and 3D
     Systems, pursuant to the terms of the merger proposal between Borrower and
     3D Systems dated April 2, 2001"

     6.  Domestic Loan Agreement Fee.  In consideration for Silicon agreeing to
amend the Domestic Loan Agreement as set forth herein, Borrower shall
concurrently pay Silicon a fee in the amount of $10,000, which shall be non-
refundable and in addition to all interest and other fees payable to Silicon
under the Loan Agreements.  Silicon is authorized to charge said fee to
Borrower's loan account.

     7.  Exim Loan Agreement Interest Rate.  Section 2 of the Schedule to the
Exim Loan Agreement is hereby amended in its entirety to read as follows:

     "2.  Interest.
       Interest Rate

       (Section 1.2):  A rate equal to the "Prime Rate" in effect from time to
                       time, plus 1.25% per annum.  Interest shall be calculated
                       on the basis of a 360-day year for the actual number of
                       days elapsed.  "Prime Rate" means the rate announced from
                       time to time by Silicon as its "prime rate;" it is a base
                       rate upon which other rates charged by Silicon are based,
                       and it is not necessarily the best rate available at
                       Silicon.  The interest rate applicable to the Obligations
                       shall change on each date there is a change in the Prime
                       Rate.

       Minimum Monthly
       Interest (Section 1.2):  N/A."
     8.  Exim Loan Agreement Maturity Date.  Section 4 of the Schedule to the
Exim Loan Agreement is hereby amended in its entirety to read as follows:

     "4.  Maturity Date
         (Section 6.1):   June 8, 2002."

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     9.  Exim Loan Agreement Audit Fees.  In the third sentence of Section 5.4
of the Exim Loan Agreement, the amount "$600" is hereby replaced by the amount
"$700", so that such sentence now reads as follows:

     "The foregoing inspections and audits shall be at Borrower's expense and
     the charge therefor shall be $700 per person per day (or such higher amount
     as shall represent Silicon's then current standard charge for the same),
     plus reasonable out of pocket expenses."

     10.  Exim Loan Agreement Early Termination Fee.  Section 6.2 of the Exim
Loan Agreement is hereby amended in its entirety to read as follows:

          "6.2  Early Termination.  This Agreement may be terminated prior to
     the Maturity Date as follows:  (i) by Borrower, effective three Business
     Days after written notice of termination is given to Silicon; or (ii) by
     Silicon at any time after the occurrence of an Event of Default, without
     notice, effective immediately.  If this Agreement is terminated by Borrower
     or by Silicon under this Section 6.2, Borrower shall pay to Silicon a
     termination fee in an amount equal to * two percent (2.0%) of the Maximum
     Credit Limit, provided that no termination fee shall be charged if the
     credit facility hereunder is replaced with a new facility from another
     division of Silicon Valley Bank**.  The termination fee shall be due and
     payable on the effective date of termination and thereafter shall bear
     interest at a rate equal to the highest rate applicable to any of the
     Obligations.

     * one percent (1.0%)

     ** or is paid from the proceeds of a merger between Borrower and 3D
     Systems, pursuant to the terms of the merger proposal between Borrower and
     3D Systems dated April 2, 2001"

     11.  Exim Loan Agreement Fee.  In consideration for Silicon agreeing to
amend the Exim Loan Agreement as set forth herein, Borrower shall concurrently
pay Silicon a fee in the amount of $22,500, which shall be non-refundable and in
addition to all interest and other fees payable to Silicon under the Loan
Agreements.  Silicon is authorized to charge said fee to Borrower's loan
account.

     12.  Representations True.  Borrower represents and warrants to Silicon
that all representations and warranties set forth in the Loan Agreements, as
amended hereby, are true and correct.

     13.  General Provisions.  This Amendment, the Loan Agreements, any prior
written amendments to the Loan Agreements signed by Silicon and Borrower, and
the other written documents and agreements between Silicon and Borrower set
forth in full

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all of the representations and agreements of the parties with respect to the
subject matter hereof and supersede all prior discussions, representations,
agreements and understandings between the parties with respect to the subject
hereof. Except as herein expressly amended, all of the terms and provisions of
the Loan Agreements, and all other documents and agreements between Silicon

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and Borrower shall continue in full force and effect and the same are hereby
ratified and confirmed.


Borrower:                                Silicon:

DTM CORPORATION                          SILICON VALLEY BANK


By /s/ JOHN S. MURCHISON, III            By  /s/ MILAD I. HANNA
   ------------------------------           --------------------------------
   President or Vice President           Title Senior Vice President
                                               -----------------------------

By  /s/  GEOFFREY W. KREIGER
   ------------------------------
   Secretary or Ass't Secretary

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