Job Description:

• 1) Casts and finishes plaster patterns used in making precision sand molds for dies, tools, and machine parts, according to specifications: Constructs boxlike enclosure around part to be cast, filling in cracks and openings with clay.

• 2) Lubricates surface with parting agent that prevents plaster from sticking to part.

• 3) Mixes plaster and pours it into enclosure.

• 4) Reinforces plaster with hemp fiber and small steel rods or heavy wire.

• 5) Removes hardened plaster cast from enclosure.

• 6) Patches broken edges and fractures, using clay or plaster.

• 7) Trims plaster pattern to tolerance by scraping and shaping plaster surfaces by hand following blueprint, using flat metal scrapers.

• 8) Verifies dimensions, using measuring instruments, such as calipers, vernier gauge, and protractor.

• 9) Makes identifying marks on pattern with crayon, inked rubber stamps, or pointed tool.

• 10) Shellacs finished surfaces to harden and smooth them.