Cost Accounting: A Managerial Emphasis, 6e
Chapter 18 – Spoilage, Rework, and Scrap
18–76
23) Marvin Randall had a background in the manufacturing of building bricks. The building brick
industry used clay and other material which were first mixed, then aged. After aging, they were molded
into shapes, retouched and fired in kilns. The materials were fairly durable and spoilage was not
significant. As a result, any spoilage that did occur was not specifically accounted for. Marvin saw the
similarities between brick and tile manufacturing and felt that he could apply his knowledge successfully
in tile manufacturing and started his business, Randall Tile Ltd. on July 1.
In tile manufacturing, as it brick manufacturing, the process starts with the selection of the raw materials
including clays. However feldspar, sand, and other materials are used. In the initial stages, it is important
that all materials are homogenized; this is done through a wet grinding process. The material output of
this process is known as slip.
Water content is then removed from the slip through spray-drying . After, the material is moulded ,
pressed and dried before the tiles are fired. Hydraulic presses are used to guarantee maximum
compaction. Consistency in the press cycle time is critical to ensure the tiles have the correct moisture
content. If the water content is too high, the tiles will crack or break.
Unglazed tiles proceed to firing, whereas glazed tiles must first be covered with one or more layers of
glaze. Firing time and temperature are important in the firing process to ensure the resulting product
meets required specifications for strength, stability, resistance and easy cleaning.
After firing, tiles are inspected for quality. Irregularities in size, shape or colouring will lead to spoiled
units. The final step is packing the ceramic tiles.
Randall Tile was organized into 4 main departments.: 1) Mixing & Grinding, 2) Moulding & Pressing, 3)
Glazing & Firing and 4) Inspecting & Packing. Randall was not manufacturing many glazed tiles, so any
glazing that was required was done in the Firing department. The weighted average method of process
costing was used in each department, however spoilage was not tracked. Marvin quickly realized that,
although the processes in brick and tile manufacturing processes were similar, tile manufacturing
required much more precision. After 3 months of operations, he estimated that he had a 50% defect rate
when considering all stages of manufacturing. Employees were frustrated by the constant changes in
manufacturing as pressing times, firing times, and temperatures were all altered in attempts to improve
quality. Furthermore, Marvin believed that both frustration and nervousness led to high spoilage in the
packing process.
Required:
What factors might have contributed to the high defect rate that Marvin noted? What steps might Marvin
have taken prior to starting production to minimize defects? What recommendations would you make to
Marvin regarding the management accounting system at Randall Tile?