The Clay Process

The clay factories in Grand Ledge all used a similar process to produce their tiles and bricks as noted in The State Journal in 1912:

“The American Sewer Pipe Co. is one of the largest of its kind in the country, and the largest in Michigan. It regularly employs 100 men. The Clay Products Company is almost as large and it gives employment to 90 men. The clay used for the manufacture of the tile by these two factories abounds in large quantities about Grand Ledge, and it is a most interesting sight to visit the pits and watch the fire clay being dug out by the men, loaded on miniature cars and drawn to the mixing machines over a narrow gauge railway. Each of these concerns have 12 large kilns in which the tiles are burned, and the completed product is shipped to all parts of the country.”

The raw material for clay was rock shale quarried from the local clay pits. This was loaded into small rail cars and transferred to the factories. In the early days, the tile plants used mules or horses to pull the cars, while the brick factory used a locomotive. The chunks of shale, some as big as a man, were ground into powder. This was put into a hopper and mixed with water to form clay.

The soft clay was then forced through casting dies to form long clay tubes. These were then sliced by thin wires into individual tile sections or bricks. The fragile wet clay or “green wares” were stacked in drying kilns to remove most of the moisture. If special shapes like “Y” branching tiles were needed, specialist workers called “Branchers” were employed. There job was to cut and paste tiles together by hand to form all special shapes and forms.

Once dried, the tile or bricks were then transferred to the kilns for final firing. Men called “Setters” specialized in stacking the kilns in certain ways to get the best firing of the products. Firing took 50 to 140 hours. For many years, salt was added during firing to create a glass-like glaze on the tiles that made them less permeable to water. After the conversion to gas firing, salt glazing was no longer needed. However, personally I think salt-glazed tile are the most beautiful; the glaze brings out the natural coloring in the clay.

Once the firing was over and the kiln has cooled, gangs of “Pullers” came along to empty the kiln. The tiles or bricks were then stacked in the yard until they were sold. Anything that broke, twisted or fired wrong in the kiln was considered a “clunker” and was removed as unsellable. Clunker tile was often crushed and sold as ground cover, while clunker bricks were thrown into heaps on the edge of the property, where they still remain today. Such deformed bricks would be seen as special “art” bricks today and sold at a premium price.