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                                  EXHIBIT 10.18

                AMENDMENT TO FORM OF SEVERANCE LETTER AGREEMENTS
                    BETWEEN THE COMPANY AND DAVID A. PURCELL





                  We are pleased to inform you that the Company's Board of
Directors has recently approved an amendment to the special severance benefit
program established for you pursuant to your letter agreement with the Company
dated February 19, 1997 (the "Severance Agreement"). The changes which have been
made to your existing Severance Agreement apply only to the severance benefits
to which you may become entitled following a change in control of the Company
and may be summarized as follows:

                           (i) The period of time for which you will be
         protected following a change in control of the Company has been
         increased so that if your employment now terminates under certain
         circumstances within twenty-four (24) months following a change in
         control, you will be eligible to receive your severance benefits under
         the amended Severance Agreement.

                           (ii) The multiple of salary and bonus to which you
         may become entitled under the amended Severance Agreement as a cash
         severance payment in connection with the termination of your employment
         following a change in control will now be paid to you in a lump sum
         rather than through a series of payments over a one-year period.

                           (iii) There will no longer be a non-compete covenant
         or other restrictive covenants in effect following your termination of
         employment in connection with a change in control of the Company.

                           (iv) The parachute tax gross-up previously provided
         you under Paragraph 5 of Part Three of your existing Severance
         Agreement has been eliminated, and any parachute payments attributable
         to your severance benefits will now be limited to an amount which does
         not constitute an excess parachute payment under the federal tax laws
         or (solely in the event of a Hostile Take-Over) the greatest after-tax
         benefit such severance benefits can provide you after taking into
         account any excise parachute tax which may be imposed under the federal
         tax laws.

                  The purpose of this letter agreement is to set forth those
changes in more detail so that your Severance Agreement will be formally amended
by this new letter agreement. Unless specifically noted in this letter, all of
the terms and conditions of your existing Severance Agreement will be preserved,
and all capitalized terms in this letter agreement will have the same meanings
assigned to those terms in your Severance Agreement as in effect immediately
prior to this amendment..

                  1. The introductory paragraph to Part Three of your existing
Severance Agreement is hereby amended in its entirety to read as follows:

                    PART THREE -- CHANGE IN CONTROL BENEFITS

                  Upon your Termination Without Cause or Resignation for Good
         Cause within twenty-four (24) months following a Change in Control and
         seven (7) days after your execution of a General Release in favor of
         the Company within three (3) days after such Termination Without Cause
         or Resignation for Good Cause, as the case may be, then (provided such
         General Release is not revoked by you prior to the end of the
         Revocation Period), you shall become entitled to receive the special
         severance benefits provided in this Part Three in substitution of the
         severance benefits set forth in Part Two hereof. However, your
         severance benefits under this Part Three shall be subject to the
         benefit limitation of Paragraph 5 of this Part Three.


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                  2. Paragraph 1 of Part Three of your Severance Agreement is
         hereby amended and restated in its entirety to read as follows:

                           1. CIC SEVERANCE PAYMENT. You shall be entitled to
         the following CIC Severance Payment:

                           AMOUNT. You shall be entitled to a CIC Severance
         Payment in an amount equal to ** times your Total Compensation
         determined as of the date of your Termination Without Cause or
         Resignation for Good Cause.

                           FORM. Your CIC Severance Payment will be paid in a
         lump sum payment (subject to all applicable withholding taxes) within
         thirty (30) days after your Termination Without Cause or Resignation
         for Good Cause.

                           OTHER TERMINATIONS. You will not be entitled to
         receive any CIC Severance Payment or any other benefits under this
         letter agreement in the event your employment terminated by reason of
         your death, disability or your Termination for Cause.

                  3. The restrictive covenants set forth in Paragraph 4 of Part
Three of your Severance Agreement will no longer be applicable in the event you
receive benefits under this Part Three following your Termination Without Cause
or Resignation for Good Cause within twenty-four (24) months after a Change in
Control.

                  4. In consideration of the additional benefits provided to you
under this amendment to your Severance Agreement, your Benefit Tax Protection in
Paragraph 5 of Part Three of the existing Severance Agreement is hereby deleted
and rendered null and void in its entirety, and the following new benefit
limitation is hereby imposed upon your Part Three benefits:

                           5. BENEFIT LIMITATIONS. The following provisions
         shall govern the Change in Control benefits payable to you under this
         Part Three.

                           (a) The following benefit limitations shall be in
        effect for any Change in Control benefits provided you under Part Three
        of this letter agreement:

                           CHANGE IN CONTROL OTHER THAN HOSTILE TAKE-OVER. If
         the Change in Control does not constitute a Hostile Take-Over, the
         dollar amount of your CIC Severance Payment will be reduced to the
         extent necessary to assure that the present value of that benefit will
         not, when added to the present value of your Option Parachute Payment
         and your Other Parachute Payments, exceed the maximum amount which may
         be paid under your Severance Agreement (as amended by this letter
         agreement) without any of those amounts being treated as an excess
         parachute payment under Code Section 280(G).

                           HOSTILE TAKEOVER.In the event of a Hostile Takeover,
         no reduction will be made to your CIC Severance Payment (or any other
         benefits under your Severance Agreement as supplemented by this letter
         agreement), except and only to the extent necessary to provide you with
         the maximum after-tax benefit under this Part Three, after taking into
         account any parachute excise tax that might otherwise be payable by you
         under Code Section 4999 and any analogous State income tax provision.

         ** CONFIDENTIAL TREATMENT REQUESTED

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                           (b) RESOLUTION OF DISPUTES. In the event there is any
         disagreement between you and the Company as to whether one or more
         benefits to which you become entitled (whether under this letter
         agreement or otherwise) in connection with a Change in Control
         constitute Option Parachute Payments or Other Parachute Payments or
         would otherwise result in an excess parachute payment under Code
         Section 280G, such dispute is to be resolved as follows:

                           (i) In the event temporary, proposed or final
         Treasury Regulations in effect at the time under Code Section 280G
         specifically address the status of such benefits or the method for
         their valuation, the characterization afforded to such benefits by the
         Regulations, together with the methods prescribed for their valuation,
         shall be controlling.

                           (ii) In the event such Regulations do not address the
         status of the benefits in dispute, the matter shall be submitted for
         resolution to independent counsel mutually acceptable to you and the
         Company ("Independent Counsel"). The resolution reached by Independent
         Counsel shall be final and controlling. However, should the Independent
         Counsel determine that the status of the benefits in dispute can be
         resolved through the obtainment of a private letter ruling from the
         Internal Revenue Service, a formal and proper request for such ruling
         shall be prepared and submitted by Independent Counsel, and the
         determination made by the Internal Revenue Service in the issued ruling
         shall be controlling. All expenses incurred in connection with the
         retention of Independent Counsel and (if applicable) the preparation
         and submission of the ruling request shall be paid by the Company.

                           The full amount of your severance benefit under
         Paragraph 1 shall not be paid to you until any amounts in dispute under
         this Paragraph 5(b) have been resolved in accordance herewith. However,
         any portion of such severance payment or such accelerated balance of
         your Performance Plan accounts which would not otherwise exceed the
         benefit limitation of Paragraph 5(a) even if all amounts in dispute
         under this Paragraph 5(b) were to be resolved against you will be paid
         to you in accordance with the applicable provisions of this letter
         agreement.

                           (c) OVERRIDING LIMITATION. You will in all events be
         entitled to receive the full amount of your severance payment under
         Paragraph 1, to the extent that benefit, when added to the present
         value of your Option Parachute Payment and your Other Parachute
         Payments (excluding such severance payment), will nevertheless qualify
         as reasonable compensation within the standards established under Code
         Section 280G(b)(4).

                  5. Paragraph 7 of Part Four of the existing Severance
Agreement is hereby amended in its entirety to read as follows:

                           7.       ARBITRATION

                           Except for the dispute resolution procedure in
         Paragraph (b) of Section 5 of Part Three of your Severance Agreement,
         any controversy that may arise between you and the Company with respect
         to the construction, interpretation or application of any of the terms,
         provisions or conditions of your Severance Agreement (as amended by
         this letter agreement) or any monetary claim arising from or relating
         to your Severance Agreement will be submitted to final and binding
         arbitration in San Diego, California in accordance with the rules of
         the American Arbitration Association then in effect. The prevailing
         party in the arbitration shall be entitled to the recovery of all
         reasonable attorney's fees and costs incurred with respect to the
         arbitration. Both parties understand and agree that the arbitration
         shall be instead of any civil litigation and that the arbitrator's
         decision shall be final and binding to the fullest extent permitted by
         law and enforceable by any court having jurisdiction thereof.

                  This letter agreement will be binding upon the Company, its
successors and assigns (including, without limitation, the surviving entity in
any Change in Control) and is to be construed and interpreted under the laws of
the State of California applicable to agreements executed and to be wholly
performed within the State of California.


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                  All terms of your February 19, 1997 Severance Agreement shall
remain in full force and effect, except to the extent those terms are expressly
modified by the terms of this letter agreement. Any severance benefits to which
you may become entitled upon the termination of your employment with the Company
will be governed solely by the terms of your Severance Agreement (as modified
hereby).

                  Please indicate your acceptance of the foregoing amendments to
your February 19, 1997 Severance Agreement by signing the enclosed copy of this
letter and returning it to the Company not later than February 4, 2000.

                                          Very truly yours,

                                          ENCAD, INC.


                                          By:          /s/   Charles E. Volpe
                                                       ----------------------
                                          Name:        Charles E. Volpe
                                          Title:       Director




                                   ACCEPTANCE

                  I hereby agree to and accept all the modifications made by the
terms and provisions of the foregoing letter agreement to the severance benefits
to which I may become entitled under my existing Severance Agreement upon a
termination of my employment under certain prescribed circumstances following a
Change in Control of the Company.


Dated:           , 2000
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                                          /s/  David A. Purcell
                                          --------------------------------------
                                          DAVID A. PURCELL