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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.

www.ndprecisionproducts.co.uk

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.'

www.midas-pattern.co.uk

A 25-YEAR THANK YOU FROM MIDAS PATTERN