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At James Jefferson Furniture Company, production consumes 80% (?) of the expenditures and employs 85% of the workers.
Most of them, 320, work on the shop floor. They are managed by 25 first-line foremen and supervisors, who report individually and in teams to the director of production (DOP). The DOP reports to the chief design officer and also has an influential role on the Operations Council, headed by the director of operations.
design shop
craft shop
raw material storage
machining shop
solid wood line
panel line
veneer line
machined parts and works-in-process storage
sanding shop
assembling shop
finishing shop
repair / rework area of craft shop
shipping department
packing
storage
loading dock
saws:
panel saw, crosscut saw, bandsaw, ripsaw
guillotines,
jointers, planers, shapers, moulders, drills, borers, sanders, routers, edgers,
lathes, edgebanders, tenoners, mortisers, dovetailers, etc.
compressors,
presses and clamps
kilns,
finishing and painting
dust
collectors, sharpening equipment
A&A Woodworking Machinery Classifieds
Solid wood has aesthetically attractive natural
advantages -- variations in pattern, density, and size. For the same reason --
inherent variation -- it also offers challenges for mass production.
non-homogeneous
variation -- color, density and pattern
hydroscopic
variation -- moisture content depending on the ambient atmosphere makes wood
swell and shrink
Note | JJFC needs to maintain an adequate skills base for handling and processing wood. Training people to use a machine is easy. Training people to use a machine well, depending on the wood, is impossible. Such expertise can come only with experience.
Fewer problems are offered by standard boards, faced with veneer and finished with suitable edgings to make uniform surfaces and interchangeable panels.
Occasionally, JJFC furniture uses decorative metal, glass, plastic, rattan, or fabric.
Almost all pieces of JJFC furniture have functional -- hinges, etc.
1) design shop
A piece or coordinated collection of furniture is designed and drawn. The dimensions, materials, and processes are specified.
2) craft shop
Prototypes are made, often by the designer.
3) raw material storage
The required raw materials are selected and carried onto the machine shop floor in batches from 200 to 1000 to minimize set-up and change-over costs.
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4) machine shop
The material is processed as specified.
6) machined parts storage
The resulting completed piece parts are then carried into the
machined parts storage. Kits of all the parts needed for assembling particular
pieces of furniture are selected according to customer orders received or
forecast.
6) sanding shop
Edgebanding, laminating and edge forming, drilling, and finally sanding. Because of the large quantity of dust, this part of the process is set into a separate ventilated area.
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7) assembly shop
The pieces are joined together 
-- doweled and
glued. Appropriate decoration and hardware are applied. Again in batches,
minimum 25.
8) finishing shop; repair / rework area of craft shop
The pieces are finished, usually polished, checked for quality,
and sent for any necessary remedial work.
9) shipping department
If they form part of a customer order, they are carefully packed and trucked to the retailers. Otherwise they are labeled, packed in protective wrapping, and placed in finished goods storage until a further customer order calls for them.
Knowledge gained during design and prototyping is made available on standard paper forms to the machine shop and assembly processes.
Knowledge gained during production is made available orally to the finishers.
While the raw materials storage is inventoried, the machined parts storage is not. JJFC manufactures over two hundreds different pieces of furniture requiring almost ten thousand unique piece parts. There are left- or right-hand versions of the same corner of moulding, which often (but not always) go together in pairs. The high rate of rejects inherent in wood means that what started out as 100 left- and right-hand pairs end up as 96 righties and 91 lefties. They never seem to get enough of the appropriate piece parts ready just in time for the assembly kits.
The DOO attempts to meet the CFO's daily control targets. Bigger batches move ahead of the smaller ones. The smaller ones take up floor space until the DSD chases down an irate customer's late order. By this time, it is more than likely that the partial assembly kits have been raided for some piece to replace a damaged part for another kit.
Almost all the machines are computer-numeric controlled (CNC). They are not connected to each other. Information flows between the machines via the memories and collective experiences of the human machine operators.
A computerized system, sometimes called material requirements planning (MRP), takes a production schedule, looks at what furniture needs to be made, accounts for inventory, and figures out what to do next, machine by machine. The DOP has always taken great pride in doing that herself. Given the way information flows, she has great doubts about the evidence she has seen that an MRP system can do it better.
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Operations:
Production