18
GTMA
SUPPLY CHAIN NEWS
Part of a four billion year old meteorite
has been machined into high precision
parts for a new range of ultra-stylish
entry system bracelets by market-leading precision
subcontract specialist
North Devon Precision Products.
The Barnstaple-based GTMA supplier was
approached to do the job by another North
Devon company, Ion Core Ltd, who needed
a precision manufacturing company with inhouse experience and expertise to machine
high-accuracy, high-quality components for
an exclusive, limited range of micro keyless
entry system bracelets.
The bracelets, known as the Senturion Key,
were for Senturion Technology, whose
entrepreneur owner Richard Dinan Ion
Core were acting for.
The job had some unique challenges. The
meteorite (known as a Gibeon meteorite) is
composed of an iron - nickel alloy with significant amounts of cobalt and phosphorus.
Its crystal structure is a classic example of
fine octahedrite and the Widmanstätten
pattern exhibited after machining, chemical
etching and polishing the material is known
for its aesthetic beauty. This is why it is
used for high-value jewellery.
NDPP first researched the physical and
metallurgical properties and composition of
meteorites to guide how they would do the
job and, as there were no 2-D drawings to
refer to, then effectively reverse engineered
the job from 3-D models supplied by the
customer.
EDM machining was used because of its
non-contact and stress-free characteristics
but NDPP was aware this might cause a
potential problem down the line.
NDPP Managing Director Nick Squire says:
"We were machining blind and didn't know if
we would hit a pocket of non-conductive
material which would render the EDM
process redundant. To combat this we created sophisticated jigs and fixtures
to hold the
meteorite in place, and believed (as it transpired)
that we could index the meteorite
around if we hit a non-conductive area."
Initially the company, which is celebrating its
40th anniversary this year, attempted using
0.25mm diameter brass wire to machine
slices off the meteorite but the hard exterior
surface of the rock caused deflection and
the wire to break. Better results (albeit slower) were
achieved when 0.25mm diameter
zinc-coated wire was used.
After two weeks NDPP had cut the meteorite into 4 slices, and then used its
AgieCharmilles wire EDM machine to wire
cut the profiles of the prototype bracelet.
The next job was to use advanced spark
erosion machines to create intricate cavities
and the delicate interlocking mechanism of
the bracelet. Some eight different graphite
electrodes (for roughing and finishing) were
machined on an Agie Charmilles HSM 300
high-speed milling machine, and the parts
were then spark eroded on an Agie
Charmilles die-sink machine.
"After our initial trepidation the machining
operations all went well," said Nick. And
one of the results to make the bracelet
manufacturing process it designed more
robust and reliable NDPP has since purchased from
fellow GTMA supplier
AgieCharmilles three new machines - a
new CUT 300mS wire EDM machine, a
new FORM 20 die-sinker and a VCE 800
Pro vertical machining centre.
NDPP machines precision parts from
a four billion year old meteorite!
ULTRA-STYLISH ENTRY BRACELET IS A FIRST
Midas - the home of MRIM and high
quality moulding - is proud to announce
it will be celebrating its 25th birthday in
September this year.
Through this publication, the company has
sent this message to its customers: "We
would like to take this opportunity to thank
all our valued customers, suppliers and colleagues for working with us and being part
of the team that has made the last 25 years
an amazing journey.
"It is through our partnerships and relationships that Midas has developed - without
these we would not have the excellent
foundation and stability which has allowed
us to grow into the renowned company we
are today."
Midas specialises in the manufacture and
supply of Ultra High Quality Polyurethane
RIM Mouldings. It has low cost, high quality
tooling systems for producing prototype
(FASTrim™) and production (MRIM™) volumes.
Substantial investment has taken place in
CAE, Traditional Skills, PuR Technology and
infrastructure which enables Midas to have
all facilities in-house. It guarantees a customer experience that truly delivers 'Quality
on Time.'
A 25-YEAR THANK YOU FROM MIDAS PATTERN