Space Age Furniture Company
The Space Age Furniture Company manufactures tables and cabinets to hold microwave ovens and portable televisions. These products aremade in various sizes and with various features, but all follow basically the same production and assembly operations. However, two of theseproducts-the Saturn microwave stand and the Gemini TV stand-have a part (no. 3079) that requires machining on a special lathe used onlyfor making that part. At present the machine is run by Ed Szewczak, a machinist who also operates other machines in Space Age's shop. Onceset up and started, the lathe can run nearly unattended. However, the machinist must be present (even if not actually attending the machine)any time one of the machines, including the lathe, is in operation. At present, Ed works a regular 40-hour week. However, due to the workloadfor producing part 3079, it has been necessary to schedule frequent overtime for him in order to finish the necessary parts on time.
Coral Snodgrass, operations manager for Space Age, has just heard from Ed's foremen that Ed is becoming unhappy about so much overtime. AsCoral knows, Ed has been with the company a long time and is an excellent, reliable employee. Skilled machinists with Ed's experience andemployment record are extremely difficult to find. Coral wonders what can be done to alleviate this problem.
Recently, Space Age began using an MRP system that has helped reduce inventories greatly and improve on-time deliveries. In fact, Space Agecarries no finished-goods inventory. Instead, everything in the master schedule is being produced for customer orders, so all products areshipped almost immediately. Previously Space Age had estimated that it cost $1.25 per week to store each Gemini and $1.50 per week to storeeach Saturn that wasn't shipped immediately. The master schedule for producing these two items for the next six weeks is shown below.
The part in question, 3079, is used in two different subassemblies: no. 435, which is used in the Gemini TV stand, and no. 257, which is used inthe Saturn microwave stand. One of part 3079 is used in each subassembly, and one of each subassembly is used in each of the final products.
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Master Schedule
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Week
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1
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2
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3
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4
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5 6
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6
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Gemini
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600
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400
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700
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500
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400 600
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600
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Saturn
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300
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400
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400
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600
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300 300
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300
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Part 3079 may be produced in any quantity since the lathe that makes it is not used for anything else. However, both of the subassemblies areproduced using the same equipment. To minimize change over time, Space Age has decided that these subassemblies should be made inminimum quantities of 1,000 at a time, although there is no problem with capacity on the equipment that makes them. In fact, an order for1,000 of subassembly 435 is due to be received in week 1, as is an order for 1,000 of subassembly 257. Lead time for both these subassembliesis one week, and no inventory is expected to be on hand for either part at the beginning of week 1. There is not any on-hand inventory of part3079, and there are no orders in process.
Ed Szewczak earns $22 per hour and gets a 50% premium for any overtime work. Whenever part 3079 is made, there is no set-up time, butprocessing takes 0.03 hour per unit. It costs $0.25 per week to hold any of these parts over from one week to the next. The cost of holdingeach subassembly in inventory is $0.75 per unit per week.
1. What options are open to Coral to address this problem?
2. How would reducing the minimum quantity of subassemblies help?
3. What are the costs of carrying excess items in inventory at each stage?
4. What is the trade-off between overtime costs and inventory costs?
Space Age Furniture Company Read "Space Age Furniture Company".
Respond to the following and include any Materials Requirement Planning (MRP) calculations:
Develop an MRP for Space Age Furniture Company using the information in the case including the production of sub-assemblies in lot sizes of 1,000. The lot size of 1,000 for sub-assemblies has produced a lumpy demand for part 3079.
Suggest ways for improvements over sub-assemblies in lot sizes of 1,000.
Analyze the trade-off between overtime costs and inventory costs.
Calculate a new MRP that improves the base MRP.
Compare and contrast the types of production processing-job shop, batch, repetitive, or continuous-and determine which the primary mode of operation is and why.
Describe ways that management can keep track of job status and location during production. Recommend any changes that might be beneficial to the company and/or add value for the customer.