Saggars & Saggar Making

Saggars (around 50 years old in 2015) in the cobbled yard at Gladstone Pottery Museum
Saggars, over 50 years old in 2019
Gladstone Pottery Museum, Longton
Photo: Terry Woolliscroft Collection  Date: 2015

WHAT IS A SAGGAR?

Saggars played an important role in the coal fired bottle oven. These fire-resistant thick-sided boxes, made from coarse local clay called saggar marl, protected pottery from the intense heat, flames, ash and corrosive gases during the firing process. They were made by hand in various shapes and sizes to contain pottery during the biscuit, glost or sometimes decorating fire in a bottle oven. On a large potbank they were made by a team of men: one or two saggar makers, a frame filler, and a saggar-makers bottom-knocker.

The word 'saggar' may come from the word 'safeguard'.

"One of the essentials in a successful pottery business is a good saggar"

Gladstone Pottery Museum is home to the largest collection of saggars in the world. The majority of the saggars at the museum came from the Garfield Works, Uttoxeter Road, Longton in November 1974. They were rescued by Gladstone's volunteers before the Garfield site was demolished.  Page down for images of the rescue.


SAGGAR TYPES  and SHAPES

Saggars of a particular type, shape and size have particular descriptive names:
  • Ovals
  • Doodle - half the size of an oval saggar. Peculiar to Alfred Clough
  • Banjos 
  • Hillers 
  • Cheese saggars
  • Square saggars
  • Skimmer saggars
  • Cup height saggars
  • Scorer saggars
  • Pigger saggars
  • Dottey saggars
  • Draw-through
  • Bidles
  • Dish saggars
More here> in The Potbank Dictionary.


MAU'ING THE SAGGAR  A film by Gerald Mee, 1981

The process of saggar making by the late Ralph Wheeldon - one of the four last saggar makers in the Potteries working at the Gladstone Pottery in Longton during the making of the film in 1981.



SAGGAR MAKING at the NATIONAL GARDEN FESTIVAL, STOKE

1986 Ralph Wheeldon entertains the crowds at the Garden Festival

Saggar maker Ralph Wheeldon at National Garden Festival Stoke 1986
Saggar maker Ralph Wheeldon at National Garden Festival Stoke 1986
Photo: Terry Woolliscroft Collection  Date: Summer 1986


THE SAGGAR MAKERS BOTTOM KNOCKER, KNOCKING A BOTTOM

Very short, 25 second, movie



"I'M NOT THE SAGGAR MAKER, I'M THE SAGGAR MAKER'S MATE"

Saggar making and bottom knocking in Stoke-on-Trent - a guide to early saggar technology.
By Paul T. Nicholson, Professor in Archaeology, Cardiff University

Most excellent and highly recommended written record of how saggars were made, together with details of the types of clay used. 'Probably the most accurate and detailed record of the art of the saggar maker ever written.' Published 2011. 
Details start on Page 705 of this downloadable pdf. herehttp://orca.cf.ac.uk/28014/1/SaggarMakerNicholson.pdf

EDITED EXTRACTS:
Clay
The clay used to produce saggars was known in Stoke as 'Saggar Marl' and was mixed with 'grog' ... in the pottery industry it can mean any none-plastic material. In the case of saggar marl the grog often comprised [crushed] pieces of brick, old saggar fragments and sand. The proportion of grog to clay varied according to clay type but could be as high as three parts grog to two parts clay ...

... saggar marl was delivered to the factory six or seven tons at a time, usually as lumps of 56 lbs each (25.40 kg). It was of two distinct compositions 'side marl' which was used for the walls of the saggar and 'bottom marl' used for the bases. Bottom marl had more grog mixed into it and the grog was of larger size than for the side marl. The six ton delivery would be divided into three tons of side and three of bottom marl. The two types of marl were dumped on the workshop floor and each would then be 'knocked with the mau' until it stood about waist high.

Saggar making
with the saggar marl dump, 'waist high' in middle of the shop
Photo: unknown source  date: unknown

At this stage most of the air would have been knocked out of the clay and the individual blocks would have been amalgamated into a single pile of side marl and another of bottom marl. However, in times before pre-mixed clay was brought to the factory, the mixing of grog with clay was done on site. A layer of grog was spread on the floor, and on top of it a layer of ground clay, another of grog and so on 'till the pile is 1 ft. 6 in to 2 ft high'. It would then be 'dug over' and sprinkled with water before being run twice through the pug mill.

Frame Filling 
Once the clay was prepared the first task was to work it on a bench. The bench was flat and had a metal 'frame' which could be dropped over it. The bench was first wetted using a sponge and then sprinkled with sawdust until completely covered. Earlier in the 20th century, and before, sand had been used to sprinkle on the bench but health and safety considerations had led to the use of sawdust as it gave rise to less dust and so reduced silicosis.

Individual slices of clay were now cut from the side marl pile, or 'dump', using a tool known as a 'grafter'. This is a spade-like tool with a flat D-shaped blade, the curve of the D being uppermost and attached to the handle (or 'stale'). These slices were cut to be only slightly thicker than the depth of the frame on the bench top. The slices were placed into the frame each running from the back toward the worker and each slightly overlapping the other by 1 to 1.5 inches. The grafter was used to trim off excess thickness in a process known as 'fettling off' and then the slices (or 'bats') were hammered down using the flat blade of the grafter such that the overlapped edges became compressed together and the whole sheet of clay was reduced to the thickness of the frame. The frame usually had only 3 sides, that nearest to the worker being open. It was not always necessary to fill the whole frame and the saggar maker used the grafter to trim the edges square where the frame was not completely filled as well as to trim the
edge nearest to him. The normal depth of a frame was 0.75 inches.

Mau'ing in 
With this done, the edge nearest the saggar maker was thickened slightly with the fingers and the whole clay sheet again sprinkled with sawdust. A mau' was then used to strike along the clay, working across it horizontally, gradually moving in rows from back to front.

The mau' itself was shaped like a warming pan and comprised a cylindrical head made from heavy oak through which the shaft passes. The flat ends of the cylinder were used to hammer the marl. The mau' was kept in a bucket of water to keep the oak head damp and to keep the wood expanded so that the stale did not come off. This practice of soaking the mau' led to handles becoming rotted and causing accidents when they broke. By the time saggar making ended as a practice the wooden handles had been replaced by metal ones. The wetting of the mau' also meant that the clay and sawdust did not stick to it when used to hammer them down into the frame.

Mr. Ralph Wheeldon (saggar maker) describes the action of 'mau'ing in' as striking the clay and pulling sideways and forwards, in other words drawing the clay to the side of the frame and toward him. Each blow overlapped the previous one to its left or right (depending on the direction of mau'ing) and one or more of those above it. The marks from each strike were very clear (as visible in the films) and it was obvious to the worker where the next strike was to be.

Making the saggar sides
Once the frame was filled the saggar maker took his measuring stick and marked the clay ready to cut into strips of the desired height for the wall. A rule, actually a wooden straight edge, was then aligned with the measured marks and struck so that it adhered to the clay whilst a blade was drawn through it to cut it into strips. The cutting was done with a tool known as a 'splice'. In recent times this tended to be an old hacksaw blade which had been bound with tape or otherwise given a handle. Ralph Wheeldon estimated that it took eight minutes to fill the frame, mau' it in and then cut out the sides.

The individual strips, still laying in the frame, were once again dusted with sawdust. A blade, known as a 'running under stick' was drawn underneath the first strip of clay, that nearest the saggar maker, to loosen it from the bench and it was then rolled around a wooden drum. These wooden drums had a circular, oval or other shaped cross-section with solid top and base (save for a hand-hole). Their walls were built up from laths to give the overall shape. The drum is placed onto the clay and rolled along the strip rolling the clay strip around it.

Bottom knocking 
Whilst this process was going on another worker, the 'bottom knocker', working at a separate bench would be using the bottom marl to prepare the base of the saggar. He too used a metal frame but this time it comprised the complete shape of the base. He used a single piece of clay somewhat thicker than the frame ring and hammered it to the correct thickness using the mau'. The film shows that the thickness of the base could be slightly greater than that of its frame. The frame was then used to help to slide the finished bottom from the workbench onto a perforated metal plate known as a 'shord'. Once on the metal plate the frame is removed and the plate carried over to the 'wheelie', a turntable on which the saggar will be completed. It took approximately three minutes to knock a bottom.

Joining the sides to the base
The drum with clay wall wrapped around it was now carried over to the wheelie and placed on top of the prepared bottom which was of slightly larger  circumference than the drum and the wall (side) wrapped onto it. The wall is now cut where the two ends met and moistened before being beaten back together. This was to ensure a strong join in the wall.

A small plank of wood about a foot or so long and soaked in water was used as a paddle to beat the walls of the saggar, helping the join, and further evening out the wall thickness. The wheelie was revolved during this process serving as spinning anvil in what was clearly a modern version of paddle and anvil work. The rim and walls were then moistened and the walls pressed against the bottom. The excess circumference of the bottom was then trimmed off using a piece of wood called a 'peg' and the walls scraped upward using a 'plucker' from the bottom so that they were fully joined. No distortion of the walls occurs because the wooden drum is still in place. A piece of wetted oak, a 'rib' is then used to wet smooth the exterior of the walls before the drum was finally pulled upwards and out of the saggar. A 'cant tool' is used to bevel the edges of the base.

A 'topping stick' comprising a piece of board tapered to a handle at one end was used to tap across and around the rim to compact it and to make sure that it was of the same height all around. A piece of strong tin, a 'topping tool' is also used in this smoothing process. The join between the walls and base inside the vessel has not hitherto been touched but was now scraped with a tool as the vessel revolved and wet smoothed.

Mr. Wheeldon explicitly pointed out that each saggar maker made many of his own tools from scraps of wood or metal. ... The saggar was now almost complete. However, a final test was necessary. A flat board or 'banner' was placed across the saggar and lifted off. The damp rim of the vessel left a ring on the board. If the ring was complete then the height of the walls was even and the job had been correctly done. A gap would mean a low spot on the wall. To ensure that the walls were even the board was given a slight tap as it was put in
place.

How long did it take to make a saggar?
It took 6 minutes to fit a saggar together so the whole process would take 16-17 minutes to complete. However, since the bottom knocker worked alongside the saggar maker the total time would be reduced to 14-15 minutes and if frame fillers were employed (below) a further 6 minutes could be removed from this time giving 8-9 minutes to produce a completed saggar.

Drying
The now completed saggar, still on its shord, was then carried into the 'hot house' to dry. After drying they would be taken to the placers who would put the new saggars at the top of a stack of filled saggars so that they could be fired. For this first firing they would be empty but could be used in subsequent firings.

Very many thanks go to Paul Nicholson for allowing me to use the above  extract from his work. It is a truly remarkable record of saggar making.


SAGGAR MAKING TOOLS

Names of special tools used in saggar making
  • Bench
  • Cant
  • Drum
  • Frame
  • Grafter
  • Mau'
  • Measuring stick
  • Peg
  • Plucker
  • Rib
  • Running under stick
  • Shord
  • Splice
  • Splice
  • Topping stick
  • Topping tool
  • Wheelie


RECOLLECTIONS - from Alan 'aj' Colclough, January 2016

My first job was at the NEWFIELD POTTERY of Alfred Meakin (Tunstall) Ltd. I was the lodge boy, and I had to count all the broken saggars and the ones still in use, every week.  Then I had to  report it to the lodge man LEN HILTON. He would then enter the lost ones in a great big ledger book - and would check for re orders.  That was the time when they did control losses.


SAGGAR MAKING with KEVIN MILLWARD

At Gladstone Pottery Museum, 25 April 2015




SAGGAR MAKER'S MARKS

Almost all saggars were marked in some way by their maker. Some with a simple cross, others with an elaborate impressed stamp. Here are just a few from the collection at Gladstone Pottery Museum.















Gladstone Pottery Museum
Saggar with 'backstamp'
Photo: courtesy Phil Rowley Date: June 2019


SAGGARS - END OF LIFE?



Saggars in a Garden Wall,  John Street, Longton
Photo: Source unknown  Date: unknown

Saggar walls
Behind the church off  Summerbank Road, Burslem
Photo: Source unknown  Date: unknown

Unknown location
Photo: unknown source  Date: unknown


RESCUING SAGGARS 

Images from an operation to rescue saggars from the Garfield Works, Uttoxeter Road, Longton. About 1500 saggars were saved from the 1939 bottle oven at the works, just prior to demolition. Volunteers emptied the oven and took numerous van-loads back to Gladstone Pottery Museum, about 500 yards away, for display.
Paul Niblett (long serving volunteer) organised the work with the late Jim Kelly. 

Longton Rescuing saggars from the 1939 bottle oven at Garfield Works Longton, prior to demolition. Images of the oven full of empty saggars with Rodney Hampson (volunteer Gladstone Pottery Museum) starting to empty the oven  Photos: Terry Woolliscroft Collection   Date: Nov 1974
Garfield Works, Longton
Images of the oven full of empty saggars
with Rodney Hampson, volunteer, starting to empty the oven.
Photos: Terry Woolliscroft Collection   Date: Nov 1974

Longton Rescuing about 1500 saggars from the 1939 bottle oven at Garfield Works Longton, prior to demolition. Volunteers empty the oven and take van-loads back to Gladstone Pottery Museum for display Photos: Terry Woolliscroft Collection   Date: Nov 1974
Garfield Works, Longton
Photos: Terry Woolliscroft Collection   Date: Nov 1974