There has been a long-standing debate about whether graphite or copper is a better EDM electrode material for aerospace applications.
For this reason, Erodex has taken a closer look at the differences between the two materials and outlined reasons why graphite is likely to be the most appropriate for aerospace EDM needs.
Due to the wide range of graphite materials available, it is proven that some EDM grades are more economical than copper. Furthermore, most comparisons do not consider the cost of machining the electrode. Significant cost savings can be made choosing graphite over copper, generated through reduced machining times and speed of cut, less production time to create electrodes, faster EDM times and better throughput from EDM machines.
Graphite also offers a wide range of material characteristics in order to allow matching of the electrode material properties to the EDM application.
In addition, it should be noted that copper does not have the ability to handle current density as effectively as graphite, which performs exceptionally well at a high current density (even with complex geometry), allowing for various intricate machined details to be designed on the same electrode. The result is that the number of electrodes required to perform a job is reduced significantly.
Further reasons to select graphite over copper electrodes for aerospace applications include EDM performance, whereby graphite is able to achieve electrode wear of less than 1% in relation to the depth of cut, while working to more aggressive machine parameters. Moreover, fine-grain graphite electrodes are able to deliver similar surface finishes to that of copper, while offering much faster speeds and less wear.
For further information www.erodex.com
TEK4 recently introduced what it describes as a world first, an EDM machine dedicated to producing aerospace engine blades and vanes. As a specialist in cooling hole drilling technology for jet engines and gas turbines, TEK4 has launched its 6G FHD SA (Small Aerospace), a fast-hole EDM drill specifically for industrial turbine production.
The TEK4 6G FHD SA incorporates full six-axis simultaneous machining and intelligent probing, as well as pre-breakthrough and breakthrough tool detection. These features are essential for machine shops in this sector as it enables them to avoid the risk of back wall impingement. The machine is fitted as standard with an automatic electrode guide changer and automatic electrode changer, which can accommodate electrodes up to 600 mm long for extended autonomy.
According to TEK4, the EDM generator works in combination with the in-house developed software. This compatibility allows for excellent metallurgical results, says the company, which is another critical parameter for this high-tech industry. In addition, the TEK4 6G FHD can be integrated in an autonomous robot cell with automatic part loading for unmanned operation. A laser ablation head can be incorporated in TEK4 FHD machines for the removal of the ceramic protective barrier. Having the EDM head and laser head on the same platform avoids positioning issues and offers reduced capital investment.
The TEK4 5G FHD machine has an X, Y and Z axis of 300 x 300 x 400 mm, with 360° rotation in the A (±180°) and C axes (360° continuous), a 600 mm drill stroke, and a maximum work part weight of 20 kg. This flexibility enables the machine to process holes from 0.25 to 10 mm diameter, and up to 200 mm deep.
For further information www.tek4.co.uk
Greg Clark, Secretary of State for Business, Energy and Industrial Strategy, recently visited precision engineering company A&M EDM in Smethwick, West Midlands to understand what drives growth and the issues facing a manufacturing SME.
The Business Secretary met some of A&M’s current and recent apprentices, speaking to individuals about their motivation to take up an apprenticeship, the work they undertake and the skills they are developing by working with experienced engineers. All of A&M’s apprentices study for academic engineering qualifications at Dudley College.
Mark Wingfield, managing director of A&M EDM, said: “We had an informed discussion with the Business Secretary on how the Industrial Strategy can accelerate West Midlands manufacturing and A&M’s initiative to develop its own apprentices.”
Added Clark: “The Industrial Strategy for the West Midlands will harness its distinctive strengths to unlock greater growth and earning power across the region’s cities and towns.”
A&M showcased engines and components manufactured for aerospace and automotive customers. In addition, Clark saw a new high-speed CNC machining centre and handheld alloy analyser in action; these were part funded by a Black Country Local Enterprise Partnership (LEP) grant to create new manufacturing jobs.
The Business Secretary discussed the practical implementation of the Industrial Strategy with senior representatives of the Black Country Chamber of Commerce, Black Country LEP, Dudley College and the EEF.
A&M has grown from a two man start-up in 2002, to 67 staff and sales of over £6m in 2018. This has been achieved using EDM and CNC machining to design and manufacture precision components and tooling for a range of UK and international customers.
For further information www.amedm.co.uk
Bowers Group has joined the Silverstone Technology Cluster (STC), a not-for-profit organisation that is headquartered at the Silverstone racing circuit in Northamptonshire.
The cluster has been backed by the UK government and highlights a market of untapped potential. As part of its membership, Bowers Group has also been invited to join the Silverstone Metrology Special Interest Group (SIG).The aim of the group is to help accelerate technological development through metrology, leading to a rise in awareness, collaboration and the sharing of best practice.
For further information www.bowersgroup.co.uk
Reading-based machining subcontractor Rodmatic has invested in a new production control system from PSL Datatrack to provide more effective management of its business, particularly with regard to production processes and customer service.
“We wanted a solution from a supplier that could understand the needs of a subcontract engineering business,” says Martin Wilson, general manager at Rodmatic. “As a BTMA Technical Member, we knew that PSL Datatrack had expertise and a good track record in our sector.”
For further information www.psldatatrack.com