Manufacturing Technology Face-to-Face
By David Millson with Richard
techdirections November, 2002
teaches the core courses in three of six "attractor
magnet" curricula in the Interdisciplinary Program at Suncoast
Community High School: Drafting Technology, Engineering Technology,
and Communication Technology. Filsinger concentrates on the end
products of student design
and CAD/CAM projects as the leverage for increased acceptance in the
job market and/or college. He satisfies that goal and keeps materials costs
at a minimum.
"We, spend $ 200, maybe a little
more, for a year’s stock," he says. Therein lie some pointers
There’s also a
side trip into the more exotic realm of machining from digital point
measurement: finite element analysis, the stuff reverse engineering is made of. It’s all
part of the end Filsinger seeks for students who matriculate through
any of his magnet areas: exposure to the full
"Then, he says, "they’re ready to target an employer
or a college with a portfolio and experience that identify them as
serious players in an expanding global market." Beyond that, he
understands his importance in helping his school fulfill its
Now in its 14th year, Suncoast Community High School was
specifically established to attract a diverse student population by
offering an alternative to the regular comprehensive high school. A
"Magnet School of Merit" and U.S. Department of Education
"Blue Ribbon School" in Riviera Beach, FL, Suncoast offers
a college preparatory curriculum with a mission to end minority
The school provides a challenging, innovative program to a
diverse student population. Each individual is empowered to succeed
in and contribute to the global society by engaging in challenging
academic course work in several unique advanced-placement programs.
Both the Advanced Placement Program and the International
Baccalaureate Organization rank Suncoast, in the nation’s 14th
largest school district, as one of the top schools in the U.S.
Filsinger has designed
his intermediate curriculum as a progression of applied skills
grouped by the stages required to use CAD/ CAM/CNC to turn unique
stock pieces into increasingly complex finished products. The
variables inherent in these projects are Filsinger’s platform for
teaching and/or reinforcing basic math skills-"real-life math
skills the kids will definitely need for their SATs," he points
Relearning basic geometry factors. "Some
students studied for their Geometry I tests and promptly forgot the
basic relationships of diameter vs.radius, how to read a ruler,
parallel vs. perpendicular and even what ‘perpendicular’ means.
"They have forgotten because," according to Filsinger,
"they weren’t shown its relevance to real life. They studied
Algebra II only so they could pass the State test, and on and on.
But when they must remember the material in order to complete a
practical project, it sticks with them."
Setting up toolpaths. Students must make tool choices
based on the smallest radius they will cut."Students must
create a mental relationship between the geometry they will cut and
the tools they’ll use to do it. They must understand the rules
about the maximum depth of any single toolpath, and they must
examine their project and calculate how many toolpaths they must
make given those parameters of pocket depth."
Project precision = precision measurement = precision thinking. "When
my students realize that, unless they’ve accurately carried out
10-based measurements, they’re, going to crash a tool into the
stock, the fixturing, or the table. All of a sudden the theoretical
becomes a practical concern. Many of them have never used a
micrometer or calipers. To do the class work, they must add,
subtract, divide, multiply; they must exercise some, rusty
Physics principles met or remembered. "Some kids haven’t
had physics, or maybe they’ve forgotten the basics. For instance,
when a student has machined a brass piece and picks it up, it’s
likely to be warm."The same action with an aluminum piece would
result in burned fingers-that’s practical thermodynamics. Link
that to the need for different coolant flow for different metals.
"It’s the same with the properties of hardness and how they
affect cutting speeds. The kids learn the different cutting
parameters for machining aluminum, brass, and acrylic. Their need to
retain information they thought was useless is brought home in an
emphatic, hands-on way."
students have carried off six Firsts and four Seconds in the
Chrysler’s Miami-regional "Build Your Dream Car"
competition. In 2000, they bagged Third, Second, and First Place in
the regionals plus the May 25"’ national championship. That
award reflects the quality of Suncoast’s education and the caliber
of students attracted to this very special secondary program.
But what technology teacher doesn’t have budget worries?
Filsinger insists that mining scrap industrial piles can
dramatically lower materials costs and provide an additional
curricular challenge. Rather than receiving a precut piece of stock
or using general shop tools to cut stock to a precut size, Filsinger’s
students receive his recycled, random-sized stock: very economical
acrylic industrial scrap.
Since the pieces are cut in random sizes, students
can’t share, machining programs. They also must learn or refresh
their skills on using precision measurement devices because they
begin each project by measuring the stock. "Some of my
colleagues use machinable, reusable wax to cut costs," says
Filsinger, "but my students need examples of their work to
augment their portfolios. This way, I keep my material costs to a
minimum, and each student can take home each of her or his
The frugal Filsinger also focuses on
keeping tooling replace-ment costs low. He requires students to
start a dry run of every project 1" above the 0,0,0. Though
each student uses toolpath verification, I want the dry run,"
he says, "because, for example, if a student fails to enter a
spindle speed while setting machining parameters, the spindle doesn’t
turn on when the program executes, the tool is forced into the work
piece, and then it usually snaps when the machine starts its run.
"A crashed dry run causes a little embarrassment, but not a
broken tool. Also, if there’s a holddown, clamp, or screw head
sticking up from their piece and they haven’t allowed for the
proper tool limits, it’s `Goodbye, tool; goodbye, budget"’
As you’d expect, beginning students in the Engineering
Technology curriculum begin designing and machining in two
dimensions. When they reach the intermediate stage, they begin 3D
design and toolpathing, with one significant variable: Though they
have predefined general project parameters, material sizes vary and
other unknowns remain that they must solve for. The projects follow
sequentially, in order of increased complexity. Here are three:
The power of the pen: One advanced project, a penholder
with base, challenges pragmatic engineering and precision
toolpathing. The turned brass penholder must be freestanding putting
normal pressure on the brass part won’t force it out of its acrylic base yet be able to slip in
and out for ease of "shipping and customer assembly" in
the real world.
"I provide details on the
shape of the brass penholder, the diameter of the bore, and the
shape of the ball end which must fit inside the base," says
Filsinger. "The brass pen holder is machined on a Light Machine
PL3000, with an eight-tool turret head. I assign my students to
compile at least three toolpaths and make at least one tool change
in the process of machining.
"Clearance, between the
brass holder and the hole, machined with a pocket toolpath into the
base, is 0.010". If done correctly, the pen holder will hold
securely, can be adjusted in a variety of positions, and can be
inserted and removed easily."
Students must design and
toolpath the acrylic base, selected from random sized stock, to
conform to standard finish characteristics. They must use concave
and convex arcs to create a swept surface around the upper edges of
the base and machine it using a flowline toolpath. Then they must
generate a contour toolpath to project their personalized engraving
onto the surface plaque.
project-cost: 25¢ to 50¢ per student transforms random blocks of
acrylic scrap into stylish business card holders. This project
teaches students how to work using levels, how to make different
geometry visible and invisible, and to generate a wide assortment of
surfaces and toolpaths. Students
must create a pocket toolpath in order to rough in the slot where
the cards go. Using a long 3/8" flat end mill to machine the
project, they can cut deeply without flaring out the top of the
project. Then they create either a ruled or loft surface, with a
slant from behind the pocket and around the bottom of the slot. This
allows the business cards to lie back in the holder. For this cut,
they use a long 5/16" ball end mill. With the long cutting
surface, the bit won’t scrape the slot edges.
The art of the design takes its form from a Coons
surface based on four concave-convex lines created on the front,
left, and right surfaces, and one right before the pocket. The Coons
surface is machined using a multi-surf rough toolpath with a flat
3/8" cutter. They complete the surface with a multi-surf finish
To complete the card holder, the kids engrave their names onto
the Coons surface. To do this, they generate a flat contour toolpath
of their name, save it as an *.nci file with a depth of 0.10".
The *.nci is then projected onto the Coons surface. Depending on
the, size and number of the letters to be created, students choose
either a 1/8" or 1/16" flat end mill to perform the
"The results are pretty dramatic," Filsinger asserts.
"Students use random stock sizes to create the project, and
they learn the value of creating text files to remind them which
cutters are used to cut each toolpath. In effect, they are
prototyping a product using fixed parameters on non-standardized
"It’s a great motivator, too," Filsinger continues,
"because, though the description of the process looks complex,
the kids have already learned the, basic skills to begin the
project. They add to their skills inventory as we work
through the project together.
proud when they see the beauty of the piece they’ve learned to
create, and they have moved up a notch on their ‘personal
I always wanted to do
this ever since I trained on Rhineros", a 3D modeling program
that accepts input from the MicroScribe. Rhino can create, edit,
analyze, and translate NURBS curves, surfaces and solids in
saw in the MicroScribe/Rhino combination a perfect compliment to his
graphics, animation, design, and advanced CAD/CAM courses. He uses
them at Suncoast to digitize the image of an old mouse for
toolpathing and machining copies with Mastercam.
Touching grid points on the mouse; with the
Micro-Scribe stylus, students loft an exact 3D model in Rhino, which
converts the data to IGES. Easily imported into Mastercam, students
now use the file to generate rough and finish multi-surface;
toolpaths. Using pocket, multi-surface, and flowhne toolpaths,
students create the grooves that separate the mouse buttons, then
project the resultant toolpath onto the irregular surface of the
mouse. Again, another complex project requiring the application of
many drawing and toolpathing tech-niques, at a material cost of
Throughout much of what Rick Filsinger has achieved over the
past seven years with Suncoast’s highly select student body--
three of 10 applicants are admitted--flows the decades of experience
of one community volunteer, Israel Levine, a retired engineer. He
brings industrial standards to bear on students’ thought processes
and working techniques. Since Filsinger isn’t an engineer, he and
Levine engage in a lot of side conferencing. Levine received the
"Community Volunteer" award from the state of Florida four
years ago for his dedication to Suncoast’s mission.
His one-on-one coaching--his gift of patient
wisdom--has changed young lives beyond measure. His collaboration on
three-dimensional analysis, a sophisticated digitizing/machining
project, with Filsinger and a group of advanced students exemplifies
the creative freedom and personal contact that raises Suncoast
students’ achievements far beyond the norm.
For more information, contact Techno-Isel,
2101 Jericho Turnpike, New Hyde Park, NY 11040. Ph: 516-328-3970,
Fax: 516-595-7498. E-mail Techno at <email@example.com
or visit Techno's website at:
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