Figure 2. John
Deere broke free
from an expensive
the maximum amount of information from each experi-
after this software
mental run. After all, a detailed study of all factors is
generally cost- and time-prohibitive if it requires many
runs. Because of this, physicists must limit the number builder guided
of factors tested to the most obvious. The contributions
experimenters to a
of the factors they assign as minor are rarely discovered.
Later, after months of testing, the experiments end. The
process shows improvement, but how much more factorial design.
would the process have improved if other factors had to design the tool as one piece to further ensure high
been studied? That’s usually not answered with the con- repeatability. This contrasted with the former tooling,
ventional approach. which used components that had to be taken apart and
In OFAT, the first factor is fixed as a “good” value, the reassembled for each new run.
next factor is examined, and on and on to the last factor. By applying the DOE experimental method, Kodak
Because each experimental run considers only one fac- saved the cost of a new stamping machine and through
tor, many runs are needed to get sufficient information retooling, increased repeatability to 100%, reduced
about the set of conditions contributing to the problem. scrap by a factor of 10, slashed inventory, and reduced
This consumes a hefty amount of time and money, along setup time from 8 hours to 20 minutes.
with running a high risk of error. Another limitation is
Software speeds DOE application
that when factors change, they generally change togeth-
er, so it is impossible to understand the best solution by For decades, a few physicists have been manually
pointing to a single, isolated factor. Traditional OFAT applying DOE principles by using algorithms found in
experimentation frequently reduces itself to no method- handbooks. During the last 15 years, the development
ology whatsoever—just trial and error and a reliance on of DOE software packages has made DOE more accessi-
common sense. In contrast, the systematic DOE ble to physicists and engineers. Today’s software is
approach provides information about the interaction of mostly menu-driven, and statistical jargon is minimized.
variables and the way the total experimental system Developers have eased the complexity surrounding DOE
works, something generally not attainable through the by increasing the emphasis on graphically displayed
OFAT approach. results over numerical tables. The software is relatively
Eastman Kodak (Rochester, New York) found DOE inexpensive, currently ranging from $100 to $1,500.
quite cost-effective when its professional imaging finish- With a little training (typically a three- or four-day work-
ing department had difficulty forming a small steel clip shop), people can integrate DOE into their experimenta-
with consistent reliability. The 4×1×0.005-in. clip, used tion strategies.
t o s eal o ne e nd of pr eloa ded p hotographi c film The first step in using DOE software is to define the
envelopes, required a tight tolerance of a few thou- factors and the range in which each factor varies. Once
sandths of an inch during a critical stamping operation the factors and their ranges are determined, the user
in which three angles and a radius were formed. Accord- enters the values into the software. The first experimen-
ing to Peter Runke, senior manufacturing engineer, tal run identifies important factors. Subsequent runs
Kodak did not know whether it needed to improve the fine-tune the critical factors. To confirm the software’s
tooling or spend several thousand dollars for a new results, the experimenter performs a traditional one-fac-
stamping machine. tor test with several data points.
After performing 32 experimental runs with DOE The advantage of DOE software is its ability to show
software, the Kodak team found that of the six factors it the physicist real-world results. DOE helps physicists
identified for examination, three were significant. Blade complete the testing process faster than the traditional
clevis (ability to split) created the main effect. Blade experimental method. Just as important, DOE reveals
shim (taper) was second, and tool pressure was third. solutions that would not be apparent without it.
Runke says this evidence proved that the fault lay in the Ski manufacturer K2 Corporation (Vashon, Washing-
tooling, not in the machine itself. This provided the jus- ton), a division of Anthony Industries, encountered a
tification for retooling, and Kodak took the opportunity number of processing problems when the company
25 The Industrial Physicist
DOE Software Vendors
Advanced Automation Corp. Experiment Strategies PQ Systems, Inc. retooled its existing molds for a new “cap”
16 Thomas Drive 1308 18th Street 10468 Miamisburg-Spring- ski design that featured a smooth, encased
Rome, NY 13440 Anacortes, WA 98221 boro Road
look. The new skis exhibited dimples, blis-
Phone: 800-292-4519 Phone: 360-299-0700 Miamisburg, OH 45342
ters, and other troublesome surface prob-
Fax: 315-337-3692 Fax: 360-299-0202 Phone: 800-777-3020
lems. The top layer of the skintight plastic
Advanced Systems F&H Simulations, Inc. casing made every blemish visible and
Consultants P.O. Box 658 Qualitron Systems, Inc. impossible to sand off. Scrap rates soared to
P.O. Box 1176 Orem, UT 84069-0658 1208 East Maple Road,
30%, says Douglas O. Hubbell, director of
Scottsdale, AZ 85252 Phone: 801-224-6914 #100
process improvement at Anthony Industries.
Phone: 602-423-0081 Fax: 801-224-6984 Troy, MI 48083
To attack the problem, K2 ran a DOE
Fax: 602-423-8217 Phone: 810-616-8001
IMAS, Ltd. Fax: 810-686-7408 screening design on 17 factors, four of
Air Academy Associates 675 Tollgate Road, Suite P which turned out important to the ski
1155 Kelly Johnson Blvd., Elgin, IL 60123 SAS Institute, Inc.
defects: core placement, core extension
Suite 105 Phone: 800-977-3248 SAS Campus Drive
material, top thickness, and base width.
Colorado Springs, CO 80920 Fax: 847-608-7848 Cary, NC 27613
DOE revealed a surprising interaction—
Phone: 719-531-07777 Phone: 919-677-8000
Fax: 719-531-0778 International Qual-Tech, Ltd. Fax: 919-677-8123 which OFAT experimentation would never
2820 Fountain Lane North have identified—between the top thickness
Applied Technology Minneapolis, MN 55447 Stat-Ease Corp.
and base width that pointed to the need for
12237 Clark Way Phone: 612-476-1449 2021 E. Hennepin Avenue,
different dimensions, Hubbell says. K2 con-
San Jose, CA 95125 Fax: 612-475-3823 #191
firmed the accuracy of the statistical predic-
Phone: 408-266-5174 Minneapolis, MN 55413-
Fax: 408-266-5174 JBL Systems, Inc. 2723 tions by conducting standardization proce-
41570 Hayes Road Phone: 800-325-9802 dures. The company made the process
DataNet Quality Systems Clinton Township, MI 48038 Fax: 612-378-2152
adjustments recommended by the DOE
24567 Northwestern High- Phone: 810-286-3800
software, which eliminated the blemishes.
way, Fax: 810-286-5446 SPSS, Inc.
K2 then put DOE to work to solve other
Suite 430 444 North Michigan Avenue
Southfield. MI 48075 John A. Keane & Associates Chicago, IL 60611 processing problems.
Phone: 248-357-2200 575 Ewing Street Phone: 800-543-5816 By a pply in g t he D OE exp erimen tal
Fax: 248-357-4933 Princeton, NJ 08540 Fax: 800-841-0064
method, Hubbell says, K2 has dropped
press downtime from nearly 250 labor hours
Domain Solutions Corp. Fax: 609-92l-1078 StatSoft, Inc.
a week to a mere 2.5 hours and has dramat-
150 Cambridge Park Drive 2300 East 14th Street
Cambridge, MA 02140 Manugistics, Inc. Tulsa, OK 74104 ically reduced delamination scrap from 1.8
Phone: 617-873-5000 2115 East Jefferson Street Phone: 918-749-1119 to 0.12%. In addition, DOE helped K2
Fax: 617-873-6153 Rockville, MD 20852 Fax: 918-749-2217
streamline many processing steps and elimi-
nate some costly materials, such as a syn-
Dynacomp, Inc. Fax: 301-984-5157 Technicomp, Inc.
thetic rubber filler.
4560 East Lake Road 1111 Chester Avenue
Livonia, NY 14487 NAG, Inc. Cleveland, OH 44114 DOE offers industrial physicists and their
Phone: 716-346-9788 1400 Opus Place, Suite 200 Phone: 800-735-4440 engineering colleagues the opportunity to
Downers Grove, IL 60515- Fax: 216-687-0637
design better parts at lower cost and in less
Exact GTQ, Inc. 5702
time. Its cost-effectiveness, greater speed,
1400 Boul, Parc Tech- Phone: 630-971-2337 Yura Technologies, Inc.
and ability to reveal design solutions not
nologique, Suite 206 Fax: 630-971-2706 16 Thomas Drive
Quebec City, QB Rome, NY 13440 apparent with the traditional experimental
Canada GlP 4R7 NCSS Phone: 800-292-4519 method make the DOE approach increas-
Phone: 418-650-2723 329 North 1000 East Fax: 315-337-3692
ingly vital in maintaining American indus-
Fax: 418-660-6901 Kaysville, UT 84037
try’s competitive edge.
Experience in Software, Inc. Fax: 801-546-3907
2000 Hearst Avenue
Mark Anderson is a principle of
Berkeley, CA 94709
Stat-Ease Corp., a DOE software
Fax: 510-644-3823 v en dor ba sed in M inne apol is
26 The Industrial Physicist