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140. Thompson Metal Corporation (TMC) supplies various types of machine tools to
manufacturing companies. TMC has always paid a lot of attention to the quality of its products.
Recently, an outside supplier has approached TMC to supply an important and intricate
component of one of its more advanced tools that TMC has been manufacturing in-house. Sam
Weiss, a junior accountant at TMC, has collected the following information regarding this
proposal.
The cost of manufacturing one unit of this component internally are as follows:
The outside supplier has quoted a price of $90 per unit for supplying this component. The
following is a conversation that took place among the manufacturing manager (Dana Rice), the
buyer (Emily Scanlon), and Sam Weiss.
Weiss: I think that we should continue to manufacture internally because we can save $1.90 per
unit on this component.
Rice: According to your report, we would save $1.90 per unit, but I do not agree with those
numbers.
Weiss: What do you mean? I have followed the same costing guidelines this company has used for
years. I have even cross-checked my numbers with historical data and know for sure that the
overhead rates which I have used are correct.
Rice: I am sure you have done your job thoroughly, but I think that our costing system is archaic.
This component is complex and difficult to manufacture. I believe that our overhead allocation
method does not accurately capture the production difficulties and the additional resources that
are devoted to the manufacture of this component. For example, a significant portion of our
quality problems are due to this component. We spend close to a third of our quality inspection
time on just this component alone, but that is not reflected. These quality problems cause delays
in getting this component to the assembly department, and that causes a delay in getting the final
product to the customers. Many of our customers are expecting just–in-time deliveries, and they
get upset when we’re late.
Scanlon: I know that the supplier that has approached us has a strong reputation for quality.
Therefore, we can rest assured that we will have negligible quality problems.
Rice: Sam, your report does not consider this additional benefit from buying outside. I would
appreciate it if you can rework your numbers to more accurately reflect the true costs associated
with manufacturing this component internally.