info-mac@uw-beaver (info-mac) (07/18/84)
From: Macintosh Evaluation Project <MAC%upenn-1100.csnet@csnet-relay.arpa>
The following article is reproduced in its entirety from pp 38-42 of the
July, 1984, issue of "Systems & Software", and is Copyright (C) 1984, Hayden
Publishing Company, Inc.
Errors in grammar and spelling are those of the article's author, not of
this transcriber.
Macintosh Factory Has A Few Soft Spots
by Erik L. Keller
Though Apple Computer Inc. may be writing a crest of the next-generation
personal computer wave, they, too, can hit snags like any other firms when
it comes to setting up a factory. So when Apple built a plant for the
Macintosh computer in Fremont, CA., it came as little surprise to employees
that it would take a bit of shaking down before it could run at full
efficiency.
The types of problem encountered by Apple are common to system
integrators:
* The lack of the factories' AGVf and other material-handlins
system to work properly;
*The decision not to manufacture analog board at the factory but to
import them;
* no testing lab to store or test computer that have not pass inspection;
* changing workflow patterns after the factory was set up; and getting
all the assembly station to work sequentially.
Instead, as one Apple employee put it, the plant represents an R&D center
that will help Apple design a new factory for future products.
COMMON STUFFING
For instance, Apple uses three different board-stuffing machines to insert
approximately 75% of all the logic-board components; remaining parts are
inserted by hand. According to Scott Marquardt, an equipment buyer for the
factory, this function will be supplanted with robots within the next few
years. The human labor in this section of manufacturing comprises 10% of the
total.
Perhaps the most automated portion of the factory is the automatic materials
handling systems. In the Apple factory, there are overhead gantries that
move computer parts from one station to another, two large automatic part
handlers that send component totes to an assembly station when they are needed,
and automatic guided vehicles (AGV) that also move boards from one station to
another. In addition, some stations are connected by conveyor belts. All
these motions are coordinated by a computer.
The AGVs move along wires imbedded in the floor and take commands from a
central computer. However, these units were not fully operational in late May
and could only be seen scurrying around without cargo. According to Marquardt,
automated handling is perhaps the most important feature of the factory.
"We don't use fork lifts on the factory floor because of the extensive damage
they can and oftimes cause." However, this system is still being installed
and movement of most assembled parts is done manually.
Though the Macintosh contains two main pc boards, only one -- the logic
board -- is assembled in Fremont. The analog board, containing the power
supply and all of the large capacitors and chokes, is assembled in Asia.
"If we built the analog board in the factory here, it would have drained
our resources and limited our capacity to produce," says Al Siy, senior
manufacturing engineer. Because the factory was initially designed to
produce both the analog and logic boards, one of the board assembly lines is
lying fallow.
GEARING UP
However, this line will be geared up within the next few months for logic
board assembly. Because this addition will effectively double the production
of the logic-board component, Apple plans to add a third computer assembly
line. In addition, Apple will make an undisclosed percentage of the analog
boards in a factory "across the street," says Siy.
According to company officials, the plant is producing 1500 machines a day.
However, this translates to one every 38.4 seconds, which is 42.4% slower than
the much-quoted figure of one Macintosh every 27 seconds. It was easy to see
why this was occurring by looking at the front end of the plant that
assembled logic boards. Though the back end of production was maintaining a
constant pace, the front was not. In fact, many stations were taking at least
a minute to do a specified task. In addition, some stations were extremely
overworked, while others had little to do.
"This is a common problem of industrial engineering," says Kim Hyland, a
manufacturing engineer, adding that one reason the line may not be moving
at top efficiency is that Apple trains its workers in the plant for many tasks.
Another possible reason is that the plant uses a significant percentage of
temporary workers. According to Hyland, approximately 15% of all workers
are temporary.
Though inventory at the factory is kept to a minimum, the factory is not
a just-in-time facility as defined in Japan. Depending on the supplier, Apple
has an inventory ranging from half a day to 30 days. (Hyland says that the
inventory turnaround averages five days.) But only 10% of these suppliers are
located within a radius of 100 miles, says Marquardt. Apple is actively
seeking local suppliers.
REJECTION RATE
According to Marquardt, the factory will not tolerate an acceptance rate
under 95%. "If the rate of rejects goes over 5% for a long period of time,
we have to shut down the line. We simply can't tolerate it." He says the
line has not been shut down.
Hyland gives figures much lower than that. Only 85% of the boards that
have components inserted into them make it to the wave soldering device.
And 82% of these boards make it through the wave-solder machine. After a
Macintosh is assembled, 82% qualify for burn-in, and 90% of these units
make it through the burn-in tester for packaging.
Apple was hoping to get production up to 2700 units/day last month, with
the eventual plan of getting 4000 units out the door each day.