Exhibit 24


                                  POWER OF ATTORNEY


     KNOW ALL BY THESE PRESENT, that, effective as of July 12, 2018, the
undersigned hereby constitutes and appoints each of S. Kent Rockwell, Brian W.
Smith, Douglas Zemba and Loretta L. Benec, signing singly in their capacity as
officers of The ExOne Company (the "Company"), as the undersigned's true and
lawful attorney-in-fact and agent to execute for and on behalf of the
undersigned, in the undersigned's capacity as an officer and/or director of
the Company, Forms 3, 4, and 5 and amendments thereto pursuant to and in
accordance with Section 16 of the Securities Exchange Act of 1934, as amended
(the "Act") and the rules thereunder; to do and perform any and all acts for and
on behalf of the undersigned which may be necessary or desirable to complete and
execute any such Forms 3, 4, or 5 and amendments thereto and file such forms
with the United States Securities and Exchange Commission and any stock exchange
or similar authority; and to take any other action of any type whatsoever in
connection with the foregoing which, in the opinion of such attorney-in-fact,
may be of benefit to, in the best interest of, or legally required by, the
undersigned, it being understood that the documents, executed by such
attorney-in-fact on behalf of the undersigned pursuant to this Power of
Attorney shall be in such form and shall contain such terms and conditions as
such attorney-in-fact may approve in such attorney-in-fact's discretion.

     The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be
done by virtue of this Power of Attorney and the rights and powers herein
granted.

     The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities to comply
with Section 16 of the Act.

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Form 3, 4, or 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.


[Remainder of Page Intentionally Left Blank]


     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of the date set forth above and in the capacity set forth below.




/s/ Jared Helfrich
--------------------------------
Jared Helfrich
Chief Commercial Officer