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History of Uhl Pottery Company

by O. I. (Mockey) Lett

(4) MANUFACTURING

(a) JIGGERING – JIGGERING WAS THE PROCESS OF FORMING THE PIECE OF WARE IN A REVOLVING PLASTER OF PARIS MOULD. THE MOULD WAS PLACED IN THE REVOLVING WHEEL AND A HANDFUL OF MORE OF THE SOFT CLAY WAS THROWN INTO THE MOULD, THEN A SHOE OR TOOL ON A HINGED ARM WAS PULLED DOWN TO FORM THE INSIDE OF THE PIECE OF WARE. THE OUTSIDE BEING FORMED BY THE MOULD, THE SHOE WAS ADJUSTED TO MISS THE INSIDE OF THE MOULD BY THE THICKNESS REQUIRED. THIS METHOD OF MANUFACTURING WAS USED FOR MAKING ANYTHING ROUND IN SHAPE, SUCH AS JARS FROM ¼ GAL., TO 6 GAL. MILK CROCKS FROM 1 PT., TO 2 GAL., ALL SIZES OF BOWLS, AND JUGS FROM ¼ GAL, TO 10 GALLON IN SIZE. THE JUGS WERE MADE IN 2 MOULDS – ONE THAT FIT ON TOP OF THE OTHER. ALSO REQUIRING 2 MOULDS WERE SUCH ITEMS AS COOKIE JARS, BEAN POTS, ICE WATER KEGS AND FLOWER URNS, ETC. IN FACT ANYTHING THAT WAS JIGGERED THAT HAD A BELLY THAT WAS LARGER THAN THE TOP AND BOTTOM. AFTER THE MOULDS WERE FILLED THEY WERE PLACED ON RACKS IN THE DRY ROOM TO DRY FOR APPROXIMATELY 24 HOURS. THE HEAT CAUSED THE PLASTER OF PARIS MOULD TO ABSORB THE WATER FROM THE CLAY CAUSING THE PIECE OF WARE TO SHRINK AWAY FROM THE MOULD. AFTER THE PIECE WAS DRY, IT WAS REMOVED FROM THE MOULD AND THE MOULD WAS REFILLED. THE PIECE OF WARE WAS THEN FINISHED BY SPONGING AND THE ROUGH SEAMS AND EDGES REMOVED WITH A PARING KNIFE. THEN IF A HANDLE WAS REQUIRED, IT WAS PULLED TO THE CORRECT LENGTH AND SHAPE AND STUCK TO THE JUG OR PITCHER.

(B) BIG WARE MACHINE – THE WEEKS BIG WARE MACHINE WAS USED TO MANUFACTURE JARS FROM 6 GAL. TO 60 GAL. THIS MACHINE REVOLVED AND USED STEEL DIES TO FORM THE OUTSIDE OF THE JAR. WE HAD DIFFERENT SIZED DIES FOR EACH SIZE JAR. THE CLAY USED AS MENTIONED BEFORE WAS STIFFER THAN FOR JIGGERING. A BALL OF CLAY OF THE SIZE NEEDED FOR THE PARTICULAR SIZE OF JAR BEING MADE WAS BATTED OUT ON A BENCH BESIDE THE MACHINE TO ELIMINATE ANY AIR POCKETS. THIS WAS THEN LOWERED INTO THE MACHINE BY AN AIR LIFT. THEN A LARGE ROLLER WAS LOWERED INTO THE DIE WHICH FORMED THE INSIDE OF THE JAR, THE OUTSIDE BEING FORMED BY THE STEEL DIE. THE CLAY WAS ROLLED UP THE SIDE OF THE DIE IN THE REQUIRED THICKNESS. WHEN COMPLETED THE JAR WAS LIFTED OUT BY THE AIR LIFT AND CARRIED INTO THE DRY ROOM. AS I REMEMBER IT TOOK MORE THAT ONE-DAY TO DRY THE LARGE JARS. THEY HAD TO BE PERFECTLY DRY BEFORE GLAZING OR ELSE THEY WOULD BLOW UP IN THE PROCESS OF BURNING, IF ANY MOISTURE WAS PRESENT UNDER THE GLAZE IN THE CLAY.

(C) CASTING – FOR MANY OF OUR NOVELTY ITEMS AND MINIATURES THE PROCESS OF MANUFACTURE WAS KNOWN AS CASTING. THE MOULDS WERE FILLED WITH LIQUID CLAY OF THE CONSISTENCY OF CREAM, WHICH WAS A MIXTURE OF CLAY AND WATER WITH A CATALYST TO KEEP THE CLAY IN SUSPENSION. THE WATER WAS DRAWN FROM THIS SLIP (AS THE MIXTURE WAS CALLED) CAUSING THE CLAY TO ADHERE TO THE INSIDE OF THE MOULD. THE MOULDS WERE KEPT FULL BY ADDING THE SLIP UNTIL THE CLAY WAS THE DESIRED THICKNESS FOR THE PIECE BEING MADE. THEN THE MOULDS WERE TURNED UPSIDE DOWN SO THE EXCESS COULD DRAIN OUT. THE MOULDS WERE THEN ALLOWED TO DRY UNTIL THE PIECE COULD BE REMOVED WITHOUT DAMAGE OR WITHOUT COLLAPSING. WE HAD ONE SEPARATE DEPARTMENT WHERE ALL THE CASTING WAS DONE. IT WAS IN A NEW ADDITION WHICH WAS BUILT OVER OUR CLAY MIXING ROOM WHICH WAS ONLY ONE STORY. AFTER ALL THE PROCESSES OF MANUFACTURE MENTIONED ABOVE, IT WAS THEN NECESSARY THAT THE PIECES BE FINISHED AFTER REMOVAL FROM THE MOULDS. ALL ROUGH EDGES AND MOULD SEAMS WERE REMOVED WITH FINISHING KNIVES AND FLAT SPONGES. ALSO, AS MENTIONED PREVIOUSLY, THE HANDLES FOR JUGS AND PITCHERS, ETC. WERE STUCK ON AT THIS TIME. SINCE WATER HAD TO BE USED IN THE FINISHING, THE PIECES WERE THEN RETURNED TO THE DRY ROOM WHERE THEY REMAINED ANOTHER 24 HOURS BEFORE GLAZING.

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