Technical Article: “A Large Scale Torch-Fired Enameling Kiln” published in SNAG News February, 2013



This article is about how a non-enamelist came to design and build (and fail and build and fail and build and then build again) a large, torch-fired enameling kiln. First I would like to add a point of clarification: this is about building a torch-fired enameling kiln, not about torch-firing enamels. This is to say that I was attempting to create a kiln environment heated by a torch in which to fuse enamels to metals without the torch flame making direct contact with the object being fired. Although a metallic surround is sometimes used to help manage and contain the heat during a torch firing, most torch-firing of enamels involve applying the torch flame directly to the surface of the metal being enameled. As Deborah Lozier points out, this will cause some discoloration at the point of contact and size limitations depend on torch size.

 What I was after was a kind of alternative enameling kiln design that might be useful in less equipped (or even portable) workshops such as a summer camp, but that might also enable more practiced enamelists to fire larger works than their current electrical kiln might accommodate. This article makes good companion reading to the technical article that immediately preceded it, regarding tig welding with enamels.


Kiln 1

My initial design was based on the beehive ceramic kiln form. Cylindrical and topped with a dome, this was constructed of #23 soft firebricks with kiln cement mortar and featured a vertical aperture by which the progress of the firing might be viewed. A raised internal turntable was constructed to enable rotation of the work and to provide an offset mesh surface onto which larger pieces might be affixed for increased stability. It was an impressive construction and an utter disaster. No amount of indirect firing with an oxy-acetylene torch would coax the enamel into fusing - the interior appeared to be too vast. We even tried bricking up most of the vertical aperture, but to no avail. 


Test piece: sewn 6” copper foil cube, white liquid base coat enamel BC 1070 from Thompson, applied with an airbrush

Torch: Oxyacetylene with rosebud tip

Result: Time-consuming debacle



Kiln 2

Deciding that we needed to set our sights lower in terms of scale (and running low on mortar) we next decided to fit the interior of a small steel trash can with a lining of fire bricks. A soldering board was cut to fit within the lid interior. We learned the hard and smoky way that the steel can needed to be sandblasted or sanded prior to firing in order to remove surface coatings that did not approve of fire. Despite the closely mitered bricks, the heat of the torch did not travel well around the interior and enamel vitrification was only achieved on the corner nearest to the torch portal. Sigh.


Test piece: sewn 4” copper foil cube, white liquid base coat enamel BC 1070 from Thompson, applied with an airbrush. Test piece was suspended from a hole in the lid and thus rotated

Torch: Oxyacetylene with rosebud tip

Result: Disappointing failure


[For the exciting conclusion, including a design that worked, see the SNAG website:]