In page links: Flat-Pack kiln, The Little Rocket kiln, Rocket Salt Kiln, Shopping Trolly Kiln

Flat-Pack Ceramic Fiber Kiln

Ian Gregory has developed many kilns over the years and his Flat-Pack kiln is without doubt his most versatile and simple design. This kiln was mainly developed for it's portableness, for use at demonstrations. It is amazingly simple to put together and dismantle and can be stored in a limited space. It is also very durrable, as it's design enables you to assemble the kiln around a piece of work and fire it in situe. The advantage of it's panels is that by varying their size they can be clipped together to form any shape around the work to be fired.

It basically comprised of panels made of ceramic fibre which are attached to a wire mesh using ceramic buttons (like over sized shirt buttons) and nichrome wire. These panels are then held together using large clips, similar to those used on car battery jump leads. The ceramic fibre attached the the wire mesh should be oversized, so that it is pushed together with the other panels when clipped together insurring a tight seal. A hole is then cut from the bottom corner of one panel to allow access for the burner. There should be a shelf placed inside the kiln, usually propped up using ceramics tubes which hold the shelf slightly above the burner, and with a 1.5" space around it allowing the flame to pass through the chamber. Once the main kiln has been erected a panel is placed on the top to form a lid for the kiln, this is offset to leave a small gap of about an inch on the opposite side from the burner to form a flue, incouraging the flames to pace though the kiln.

Building your own Flat-Pack kiln

The following components needed to build a Flat-Pack kiln can be bought from Scarva Pottery Supplies.

1.) Roll of Isofrax Ceramic Fibre Blanket* (96 density), Size 2' wide by 12' long and 2" thick. This is enough to build a 2' x 2' x 2' (8 cubic feet) kiln comprising of 4 sides, a lid and a base.
*(This is an inorganic, needled insulating blanket manufactured using long spun fibres, cross locked through a unique forming process to produce a blanket with good handling strenght and has high temprature performance caracteristics up to 1260 degrees celcius. It also meets European Safety regulatory requirements.)

2.) Single Propane Burner Kit capable of firing kilns between 5 - 11 cubic feet in capacity. This comprisess of 1 straight burner, pressure gauge, flame-failure safty device and 2 metres of metal braided hose ready to connect to a 19kg propane cylinder. (Gas burners are also available from Steadmark Ltd.)

3.) Roll of thick Industrial Lining Foil used as a layer between the weldmesh sides and fibre. 4 metres (13.5') long.

4.) Coil of Nichrome Wire to firstly, thread through ceramic buttons, then the ceramic fibre, foil lining and finally tied to the Weldmesh sides and lid on the outside.

5.) 16 x Heavy-Duty Metal Spring Clips for holding the sides and lid together.

Items which you will also need to obtain:

A. Make and fire 40 or more ceramic buttons.
B. Obtain 5 Weldmesh panels (2' x 2') which make up the four sides to the kiln and the lid, from your local builders merchant.
C. Collect enough old bricks for a kiln base to then cover with one 2' x 2' square of Ceramic Fibre.
D. Then you will need a 19kg Propane cylinder

 

To obtain more information and costs on materials please visit www.scarvapottery.com

For more information on the building your own kilns please read Ian's books on Kiln Building and Alternative Kilns. published by A&C Blacks.

The Little Rocket Kiln

This small test kiln for stoneware glazes was originally designed by Gus Mabelson at his studio in Southern Ireland. I have fired many of these kilns, differing the size and adapting the overall measurements to suit the volume of the chamber. the smallest was about 20 cm high and 15 cm in diameter which can be fired very fast to cone 9. The support frame is made from wire mesh which is lined with a double layer of 2.5 cm thick ceramic fibre blanket held in position using pre-fired ceramic buttons and nichrome wire. There are three sections: the base with burner port and the upper chamber with a chimney on top. The height can be varied to suit requirements. The lower section should always be a minimum 15 cm in height, allowing space for the burner port and the props that support the base shelf above the flame. A small off-cut of ceramic fibre blanket is used to cover the chimney vent, giving control of the atmosphere at all stages of the firing.

The Rocket Salt Kiln

This is an addaption of the Little Rocket designed to fire salt glaze. Since the ceramic fibre blanket breaks down in a salt vapour atmosphere, this version is lined with clay sections thrown or coiled to make the inner wall, using a strong grogged clay which is then painted with batt-wash to prevent the sections sticking together. There are two additions at the side of the main chamber. The first is a port large enough to charge the salt into the kiln and the second a port for removal of draw rings, checking the cones and glaze build-up. Once the three sections have been fired themselves they are covered with ceramic fibre as insulation.

Walking the Dog Kiln (Shopping Trolley Kiln)

Ian Gregory's mobile kiln demonstrated at the International Ceramics Festival, Aberystwyrh, was a great success. He explains how to make one from a redundant shopping trolly. First find a supermarket trolly from your nearest canal, car park or scrapyard. Most of these have an inner section to place your bag; remove this and use it for the room section using nicrome wire to attach it. Some of these carts have another section on the inside and it can be used to mount the burner on the front. When the basic frame is adapted the cart can be lined with ceramic (non-toxic) fiber held in position with pre-fired ceramic buttons and wire staples twisted through the blanket and attached to the frame.

The average trolley will create a kiln of about eight cubic foot (internal space) and once the lower shelf is in position a packing space of six cubic foot, that is unless you happen to find a family-sized trolley for a bigger chamber. The gas burner is mounted on the front allowing enough space for the heat to develop into the chamber below the first shelf. The lid should be lifted about a inch at the top front by placing an off cut of fiber under the edge to create a gap: this will vent the gas and provide enough draft for the firing. One layer of blanket will be adequate for both biscuit and raku, firing to around 1100c. A thermocouple can be pushed through the chamber walls at any point to monitor the internal temperature. Should you wish to go to stoneware temperature, a layer of blanket will be needed to create a fiber wall of two inches thick to be effective.

If you want to be really ethnic, wear a sleeveless T-shirt and bandana around your head and through small bags of wood ash into the chamber at the height of the firing and allow enough time for this to flux - instant anagama. The firing for biscuit and raku is around ten minutes and stoneware about thirty. One of the main advantages of the kiln is that it's easy to construct and cheap in materials and fuel, with added benefit that you can place a small fuel bottle on the tray at the base and walk the dog at the same time as firing. Since the lid is a low temperature you can also cook pizza on the top.

(For more information please see Ian's books on Kiln Building and Alternative Kilns).

 

Side view of Shopping Trolley Kiln with burner in position