The Papermaking Process

Papermaking Processes

Paper is made from vegetable cellulose fibres, and originally, in the UK, cotton and linen rags from old clothes was the raw material source. The rags were sorted, cut-up, washed and transferred to an oak tub filled with water.

They were beaten into a pulp by a stamping machine, made up of wooden hammers lifted and dropped by the action of cams attached to a shaft turned by a water wheel. This pulp was then diluted with water and transferred to a wooden vat, where the vatman dipped a square mould, one inch deep with a fine wire-meshed bottom, into the pulp.

This formed a thin matted layer of fibres, which by careful shaking to get an even spread and to allow the water to drain out, formed a delicate sheet of paper. The mould is then passed to the coucher who up-turns it, transfers the wet sheet onto a felt blanket, and stacks it on top of other felted sheets. The levermen then take the stack to a press where the surplus water is forced out with a levered screw.

After this the sheets were hung in a loft to fully dry. If the paper was to be used for writing, it was dipped in a bath of animal glue, alum and vitriol to make it suitable for the correct up-take of ink. This is called 'sizing'. Pressing and drying was then repeated and the paper was cut to the correct size, wrapped and packed, and despatched to the customer.

The development of the Hollander beating engine to replace the stamping machine increased the rag pulping rate, and led to the development of the paper machine, by Louis Robert in 1799, which produced rolls of endless paper, to replace the individual sheets made by the hand made process. The emergence of paper making machines led to further improvements in production rates in the mid-nineteenth century.

During this period, large steam-filled metal cylinders, and tubs of glue, were installed on the machine to dry and size the paper in one operation. Calender rolls were also developed to improve the paper smoothness. Continuous technical improvement has produced modern paper machines which are computer controlled to produce quality paper to exacting standards at over 30 tons/hour.

Shortage of rags necessitated the use of esparto grass as a papermaking fibre, in 1861. This was brought in bales from North Africa, cleaned, dusted, and cooked into a pulp with caustic soda in a large digester, then washed and bleached. Effluent problems led to the closure of mill pulp plants by the 1960s, and imported wood pulp was used.

To supply printers with the correct sheet size, cutting machines were installed to split and chop the paper, before it was sent to the finishing ’salle’, where each sheet was inspected for defects, counted into reams, guillotined to exact size, wrapped and delivered. Modern conversion plants precision cut, electronically check, and automatically pack the paper.

In the early twentieth century, the pursuit of higher quality printing led to the development of coated paper. This involved an applicator roll transferring a layer of coating mix to the paper surface, and the excess metered-off by a brush, and then dried by passing through a heated room festooned on wooden poles. The coating mix was mainly china clay and casein adhesive in water. The surface was polished smooth using a large supercalender. Improvements were made by replacing the brush with high pressure air, and then by the 1960s, a flexible blade. Gas fired drying ovens replaced the festoons.

Allan Dickson who worked in Dalmore Mill from 1964 - 2004 talks about working on the ‘breakers’ then ‘beaters’.

Allan Dickson talks further about the 'beaters'.

Danny McClure who worked in Inveresk Mill 1958-1962 and Valleyfield Mill 1970-1975 talking about working with Calenders.

Allan Dickson talks about work clothes in the Mills