ND Precision Products demonstrates out-of-this-world performance...quite literally.

This Barnstaple-based company, celebrating its 40th anniversary this year, was recently confronted with a manufacturing challenge that had them literally scratching their heads (initially at least) as the project involved them machining high precision parts from a meteorite!
Explains Nick Squire:
“In Autumn 2013 we were approached by James Marchant from Ion Core Ltd in North Devon acting on behalf of Richard Dinan, entrepreneur and co-owner of Armour Surveillance Security Equipment and Technology Ltd.
“James was looking to find a local precision manufacturing company that had the in-house experience and expertise to machine high-quality, high-accuracy components for a new, exclusive and limited range of ultra-stylish and ultra-sophisticated micro keyless entry system bracelets (known as the Senturion Key) for London-based and Dinan-owned Senturion Technology Ltd.
“What was particularly exciting about the project was that the raw material used to machine the components was to be a 4 billion year old meteorite!”
The meteorite (known as a Gibeon meteorite) is composed of an iron - nickel alloy containing significant amounts of cobalt and phosphorus. The crystal structure of the meteorite provides a classic example of fine octahedrite and the Widmanstätten pattern exhibited after machining, chemical etching and polishing the material is renowned for its aesthetic beauty and explains why it is used for high-value jewellery.
“We accepted the challenge but prior to the meteorite arriving at our facility we spent time researching the physical and metallurgical properties and composition of meteorites in general and developing initial thoughts and ideas about the machining methods we would/could employ.
“It’s worthwhile remembering that there were no 2-D drawings to refer to with regard to the bracelets so we had to effectively reverse engineer the job from 3-D models supplied by the customer.”
Owing to its non-contact and stress-free characteristics it was determined that EDM machining was the best process to use for machining the meteorite - however NDPP were aware that this method could create a potential problem down the line.
Because the composition of the meteorite was not known the issue concerning the EDM machining of conductive non-conductive material could have scuppered the machining method adopted.
“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.”
NDPP cut the meteorite on a high-performance, high-precision AgieCharmilles wire EDM machine.
Initially the company 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 2 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 involved using NDPPÂ’s advanced spark erosion machines to create intricate cavities and the delicate interlocking mechanism of the bracelet.
For this a total of 8 different graphite electrodes (for roughing and finishing) were machined on an AgieCharmilles HSM 300 high-speed milling machine, and the parts were then spark eroded on a AgieCharmilles die-sink machine.
“After our initial trepidation the machining operations all went well.
“But having manufactured the first bracelet (and with more being ordered), I made the decision to invest in the latest EDM and milling machine tools in order to make the bracelet manufacturing process we had designed more robust and reliable”.
After attending GF Machining SolutionsÂ’ Open House in October 2013, the company purchased three new AgieCharmilles machines - a new CUT 300mS wire EDM machine, a new FORM 20 die-sinker and a VCE 800 Pro vertical machining centre.
All three machines, since their installation at NDPPÂ’s facility in December 2013 are being put through their paces machining the meteorite.