Pat Johnson Enamels


Enameling FAQ
First Steps on Making an Enamel Image in Copper

CONTENTS
Background Information
First Steps
Firing
Backing
About Trivets
After Firing

FIRING

 Once the copper is covered with a coat of enamel, the piece is balanced on a trivet so its back is not resting on the trivet. The work is put into the kiln with a long-handled fork and fired. How long this firing should be depends on what kind of enamel is being used on this first coat. If the first coat is flux, then the work should be left in the kiln until the enamel is thoroughly melted and bright orange in appearance. Then, on cooling the required transparency will have been achieved. If the firing is too short, the enamel will appear opaque maroon.

If any of the opaque enamels are used as the first layer, the firing should be shorter and the work removed from the kiln while the surface still looks a bit bumpy, which is called the orange peel effect.

These first firings often take approximately one minute, but do not assume that all firings are one minute. If the kiln is hot, i.e. if the firing chamber is bright yellow, the firing could be as short as 30 seconds. If the kiln is cool and the interior looks dull red, the heat may not be high enough to cause transparent enamels to become clear, no matter how long they are fired.

In the case of low firing, the name given to simply melting enamel on to the metal or a previously fired enamel surface, the enamel and its trivet will still look dark as they sit in the kiln. Although the surface of the work will be shiny (it will reflect the fork held above the surface) the surface will appear bumpy. It is wise to fire only to the orange peel state if there are intended to be many applications and firings before the work is completed.

For high firing, necessary to get the flux to become clear, a hot kiln and a slightly longer firing time is required. The work and the trivet will be seen to glow red and become the same colour as the interior of the kiln.

There is no set time for the length of firing because the time can be affected by the size of the work relative to the size of the kiln and of course by the temperature of the kiln when the work is put in. If the appearance of the firing chamber is dull red, probably the kiln is too cool to fuse the enamel to the copper. If it is piercingly yellow, then it is too hot. The actual temperature can range from 750-820C.

In general the firings should only just fuse the newly applied enamel on to the layers below. But the last firing, once all the elements of the picture/design are assembled, needs to be hotter in order to achieve a flat surface and to ensure the mature development of the colours.

C O N T I N U E

top of page

 

Home E-mail Statement Links Gallery
Enameling FAQ Working with Burnham Signs

 

2 Colors Flying Galaxy Orange Abstract Palms Leaves Water Snail Soup Still Life Untitled Art Garden Bowls Osram Fruit Deer Nudes

Pat Johnson © 1997-2007