Print, Photographic

Black and white photographic print mounted on fabric depicting women operating decorating equipment at the Champion Spark Plug Co.
Caption reads: Photograph 24
This shows the decorating process with the printing presses mounted on the electrically heated decorating kilns. These kilns consist of 20 slightly inclined tubes each running from the gate described in the previous photograph, thru the whole length of the metal box or furnace housing. The delivery ends of these tubes are seen in the immediate foreground of the picture, projecting from the end of the box. Each tube is a miniature tunnel kiln, whose diameter is such that the cores car easily be pushed thru. The cores, as they progress into the tubes, are gradually warmed and reach a maximum temperature of 1600 F. (red heat) in the middle of the tubes. They then begin to cool, coming from the tubes at a temperature which permits storing in boxes. The cooling is helped by blowing air up the tubes in the direction opposite to that of the flow of the ware.
The firing of the decorated core is done for the purpose of making the imprint absolutely permanent. This is accomplished by causing the special color composition to fuse and become a part of the glaze.