Kappius Components - pawl ring & toothed drive ring & pawl for rear hub in durable tool steel - made with EOS DMLS Additive Manufacturing

1. Customer Case Study Lifestyle Products
Facts
Challenge
Design and manufacture highly
complex hubs which transfer
more power from pedal to wheel.
Solution
Produce innovative and extremely durable drivetrains for
cyclists with an EOSINT M 270.
Results
• acy: optimized hub design
R
increases drive force
•
Innovative: design determines
production method and not
vice versa
•
Economic: rapid product
development makes twoperson company competitive
• Indestructible: maraging
steel withstands high loads
Swiss-born cyclist, Christoph Sauser, the 2012 cross-country world champion, is shown riding Kappius hubs at
“The Leadville 100” marathon mountain-bike race (Leadville, CO) in August 2012. He placed second in this race and
later in the year won the Swiss national title, also using the innovative hub design (Source: Kappius Components).
Cyclists Take Additive Manufacturing for a Spin

2. Kappius Components uses Additive Manufacturing for
trailblazing bike hub/drive assembly
To American inventors, the “home garage” has always been a symbol of possibility – a place for
Short profile
tinkerers to create and innovate. More than a century ago, the Wright brothers founded a cycle sales
Kappius Components manu­
and repair business from a modest storefront and soon after invented a bike hub that was self-
factures and distributes
oiling. Everyone knows what they did next in the field of aviation. Harley Davidson’s motorized bikes
innovative hubs and bicycle
were born in a backyard shed. HP’s Hewlett and Packard and Apple’s Jobs and Wozniak helped define
components. The company
the modern computer age from their suburban start-up shops.
is based in Littleton, Colorado
And garage-based entrepreneurs are still at it in the 21st century. About four years ago, Russ Kappius –
(USA) and was founded
mountain-bike enthusiast, winner of six Masters racing titles, and a research geophysicist/software
by inventor Russell Kappius.
developer – worked out a design for a novel oversized hub and high-performance drive assembly that
transfers more power from pedal to chain to wheel.
Address
Kappius Components, LLC.
6623 Big Horn Trail
Littleton CO 80125 (USA)
www.kappiuscomponents.com
Challenge
long turnaround time. In late
shell, as well as the drive
First of all, Russ Kappius and
2011 they discovered Direct Metal
assembly housed inside it. The
his son Brady – engineer and
Laser Sintering (DMLS). This
assembly is comprised of three
pro mountain-bike rider – tried
Additive Manufacturing techno-
major parts: an outer drive ring,
technologies like water-jet cut-
logy met their rapid turnaround
an inner ring with 60 teeth,
t
­ ing and wire electrical discharge
needs and enabled them to pro-
and eight pawls, which engage
ma­ hining (WEDM) to tweak the
c
duce parts to exacting specif­cai
in pairs with the teeth on the
design of their hubs step by step.
tions and with additional design
inner ring. This setup functions
However, either the process was
complexity.
like a ratchet allowing forward
motion while preventing back-
limited in its capacity to produce
dimensionally accurate and
Solution
complex parts or the produced
The beauty of the lightweight-
parts did not meet the required
yet-durable hub comes from
The technological advance in the
specifications and had a fairly
the handmade sleek carbon-fiber
system comes from two develop-
ward motion.
ments: the oversized design – it’s
about twice the current standard
diameter – and many more points
of engagement. While the most
The Kappius rear hub is a
groundbreaking lightweight,
durable, oversized design. Its
carbon-fiber housing con­tains a drivetrain assembly
comprised of three components
including an inner pawl ring,
a toothed drive ring, and pawls.
The components are all manufactured from an extremely
durable tool steel using Direct
Metal Laser Sintering (DMLS)
(Source: Kappius Components).
standard drive trains have 18 to
36 points of engagement the
Kappius hub is built around a drivetrain with 240 points of engagement. So the pedal can engage
every one-and-a-half degrees

3. and give the rider an extra
The final assembly is done by the
new parts out to our customers
Last but no least the bike-hub
quarter- or half-pedal stroke.
father-son team in their home
fast,” remembers Russ Kappius.
creator summarizes the benefits
These features allow a cyclist to
shop.
“We had to leverage our time to
of DMLS: “The essential asset
market to stay competitive.”
is design freedom. Number two
translate the act of pedaling
into increased drive force which
Results
is great for racing and highly
For two years, Russ and Brady
A typical order of ten drivetrain
followed by the lead time.”
technical riding. “Our drive
Kappius field-tested additive
assemblies requires two builds on
And then there’s also the rider
assembly is a critical innovation,”
manufactured versions of their
an EOSINT M 270. With the help
experience. “People just love
explains Kappius.
hub and tweaked its design.
of a software the components
the hub,” says Russ Kappius.
Already in the first week of field
can be arranged on the machine’s
“They’re faster and fun to ride.”
With DMLS Russ Kappius was
testing, the elder Kappius won
build platform to maximize output:
able to redesign the pawl itself
a race using the latest hub as-
ten outer rings, ten inner rings,
and add a 1-mm cylindrical basal
sembly. “We went from concept
and 80 pawls (eight for each
extension. This positioned them
to bike-ready components in
assembly), plus a few extras. Run
better when they engaged. The
about a month,” enthuses the
time is around 25 hrs. per plate,
Additive Manufacturing technolo-
sportsman. “I’ve never been able
or 50 hrs. total for ten assem-
gy “grows” parts, according to a
to move that quickly before.“
blies. Production is accelerating
“As a software engineer, I am
fast for the young company. In
able to change anything at any
3D digital model, layer by layer in
is the material strength closely
a bed of powder. A focussed laser
Kappius Components’ hubs have
2012 they sold about 100 hubs
time to make the code better.
beam fuses the powder by follow-
been through several design
assemblies and are projecting
With DMLS, I have similar
ing the contours and inside area
iterations since the “garage doors”
sales of 500 in 2014. The hub is
flexibility. It allows me to make
of the parts cross-sectional slice.
opened for business in 2008. The
shipped out to early-adopter
small design changes and
Once one layer has been com­
move to Additive Manufacturing
cyclists around the world.
almost immediately test them
pleted, the powder bed is lowered
has accelerated the speed of
by a few micrometres and the
improvements. “DMLS has freed
Since durability was of prime
process begins again. Following
us up to make improvements on
importance for the application,
the run, the parts are removed
all of the elements in the system,”
Kappius selected maraging steel
“DMLS has freed us up to make
from the machine. On a CNC mill,
says the elder Kappius enthu­ iass
from the available materials. The
improvements on all of the
the manufacturing support struc-
tically. In addition, the tech­­
-
heat-treatable metal is charac­
elements in the system. Our
tures are removed and an extra
nology has also helped level the
terized by excellent hardness and
drive assembly is a critical
20-thousandths of material from
playing field between the two-
strength properties. Russ Kappius
innovation.”
the back side of the part is planed
person company and the bigger
is pleased with the results. “The
down. This creates a machined
players in the bicycle industry.
tool steel is super strong,” he
Russ Kappius, inventor
finish. Afterwards, the components
“Because we’re a start-up, we
says. “I haven’t had a single hub
and founder of Kappius
are moved to a kiln and hardened
quickly learned that we needed
failure. Even the big manufactur-
Components
to a value of 52 Rockwell C.
to make design changes and get
ers can’t say that.”
on the bike. That’s the beauty
of the technology.”

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Think the impossible. You can get it.
Status 6/2013. Technical data subject to change without notice. EOS is certified according to ISO 9001.