Pluck and Dust Overglaze Printing by Hot Press

‘Pluck and Dust’ Overglaze Printing by Hot Press

 This technique was in use at the Spode factory from the early 1800s. The difference from the method described by Brolliet is that the oil is transferred from the paper to the pot before the pigment is dusted on.

 Stage 1: engraving or etching the copper plate

 The first stage was to engrave the design into the surface of a copper plate. Engraving means cutting into the metal with a sharp steel tool called a burin, or indenting dots with a punch. Sometimes the plate was etched as well as engraved. Etching uses acid to bite into the surface of the copper. The plate is first coated with a wax which protects it from the acid and is known as a ‘resist.’ The design is then lightly scratched through the wax. The plate is then exposed to the acid. The acid bites into the copper wherever the design has been scratched through the wax. The result of both engraving and etching is a plate with the design cut into its surface.

 Stage 2: transferring the design from the copper plate to the tissue paper

 The printer heated the copper plate and rubbed fine oil with just a trace of pigment into the engraved lines. Heating the plate made the mixture run better into the lines. The printer carefully wiped the mixture off the surface of the plate, leaving it only in the lines. The printer then took a sheet of tissue paper dampened with a mixture of water and soft soap. He placed the sheet of tissue paper on the plate and passed the two together through a hand-printing press. This transferred the oil from the copper plate to the tissue paper. The paper was then carefully peeled off.

 Stage 3: transferring the design from the tissue paper to the pot

 The paper was then pressed on to the pot, transferring the design in oil on to it. The paper was carefully peeled off. Powdered pigment was then lightly dusted on to the pot. The pigment stuck only to the parts of the pot that were oiled.

 Stage 4: fixing the print on the pot

 The pot had already been dipped in glaze and then fired before the print was applied, so this was an overglaze print. It was fixed by firing at about 750 degrees Celsius, a lower temperature than that of the glaze firing, which was at least 1000 degrees Celsius. The print was therefore less firmly fixed than the glaze below it and might be damaged by wear over time.

pluck & dust

detail of pluck & dust convolvulous design on a gold ground, for full catalogue entry click here

http://printedpottery.m4interactive.com/how-was-it-made/pluck-dust-overglaze-printing-hot-press