By Jeff Sipes
Next time you go on a gemba walk, put your- self in the shoes of the machine operator, the welder, and the press brake operator.
If they are cherry-picking the next job based on
what is easiest, has the least changeover, or has
the loosest standards, then they might be running
what you don’t need and not running what you do
need. Put yourself in their shoes. In the absence of
better direction, can you be critical of the choices
If you were doing their job, how would you know
what to do, how to do it, and what comes next? If the
answers aren’t obvious, then their work areas might
be candidates for some visual cues.
The Traditional Work Area
Let’s visit Fred, a welder in the fab shop. Fred has
been around for a lot of years and knows the job as
well as anybody. His work area is like many others
in the fab shop. The parts to be welded are placed in
any open space in the general area and are expected to be welded into assemblies sometime soon. At
best, Fred’s supervisor might come around and tell
him to run a certain hot job next.
But overall, Fred has little in the way of a forward-
looking schedule. So Fred needs to decide which
job to run next. Maybe he sees that another order
for the parts he just ran is scheduled for two weeks
from now and he can use the same setup. Or may-
be he knows that one of the jobs in the pile is easy
to run and has a large batch size. Or he could hunt
down the supervisor to get some input on priorities.
In all these cases, the heat is on Fred to figure it out
… and he will. The question is, will he run what is
This scenario sounds a bit harsh. Can an operation really be that loose? Do we really expect Fred
to make these important decisions without giving
him enough information, ground rules, and guidance to know the answers? If you are willing to take
an honest and objective inward look, you might be
surprised. What do we do to improve the situation
and help Fred be more effective? How about some
Visual cues and signals help employees perform
their jobs and, ultimately, make their workday easier. Cues and signals can be simple and yet extremely
effective. In the lean body of knowledge, we refer to
these visual cues or signals as visual controls. Typical visual controls in the fab shop include:
Aisle floor markings. If you do not have aisle
markings on your floors, how can you expect people
(employees, vendors, customers, and other visitors)
to know where it is safe to walk? How do you know
what the traffic flow for materials is supposed to be?
I never cease to be amazed at the power of a piece
of yellow tape on the floor. That tape helps define
space and instill discipline.
Incoming and outgoing material floor mark-
ings. Floor markings at the workcell can define how
space is intended to be used. If incoming materials
arrive on skids or in totes, mark the space where
material handlers should drop the material so em-
ployees know the status of incoming work. The
same applies to outgoing material. Mark the floor
so that, after a quick glance, everyone can tell the
status of materials in the area.
Andon signals. Used to indicate status, an andon
signal communicates that either some action is required or that everything is OK. The signal can be
visual or audio. If the signal is based on lights, then
the green light means all is OK, blue might mean
material handling is needed, and red might indicate
an equipment issue that requires maintenance. As
long as employees can see or hear those signals,
they have an effective way to communicate with
their support resources.
Production control visual board. Posted at an
individual work center or at the department level,
the production control visual board shows information about schedules, quality issues, safety priorities, and customer feedback, plus whatever else
is important in your operation. You can tailor the
content to meet your needs. These boards are most
effective when used with daily standup meetings to
Red and green replenishment signals. These
help employees stay on top of incoming components. For instance, consider corrugated material
in your shipping department. If corrugated sheets
lie flat on the floor against the wall, you could use
the wall as part of your replenishment signal. Determine the maximum number of corrugated sheets
you should hold, as well as the number of sheets you
should have at the point you send the replenishment
signal to your vendor. Now stack that number of corrugated sheets and mark the height of the stack on
the wall. Paint the wall red from the floor to that
mark. Then paint the wall green from the replenishment height to the height of the maximum number
of sheets. When you pull a sheet for use, as long as
the wall is still green, all is OK. The moment you pull
a sheet and red appears, then send the replenishment signal. This is about as simple and effective a
replenishment system as you could possibly have.
Container pitch signal. The pitch is the amount of
time it takes to fill a container, move it downstream,
and retrieve another container to keep producing.
One client used a container sized to hold 30 minutes’
worth of product—that is, a 30-minute pitch. This
created a predictable, easy rhythm in the operation.
Read more from Jeff Sipes at www.thefabricator.com/author/jeff-sipes
How about some visual cues?
The right visual cues can bring rhythm to the fab shop