System Technologies has progressively upgraded from its original PAMS off-line programming system to the latest version of EdgeCAM, using EdgeCAM Solid Machinist for Parasolids.It was the capability to respond to special customer requirements that led Ulverston-based System Technologies to manufacture a batch of satellite tags for attachment to grey seals to enable the Sea Mammal Research Unit to track their movements. Anthony English, Chief Industrial Designer explains how the use of EdgeCAM computer-aided manufacturing system from Pathtrace of Reading enabled the company to develop the most appropriate machining programs. 'We had to combine as much robustness in the aluminium tags as we could while keeping them light in weight.
It was also important that we created and machined a shape that would not impede the mammal through the water.
As the tag was glued to the seal's coat it became detached when the seal moulted.' Ulverston-based System Technologies has machining requirements similar to those of many specialist engineering companies.
Batch quantities are small, one-off jobs are common with longer runs tending to be between 50 and 100 with a rapid turnaround.
This means a high level of flexibility is the order of the day and fully integrated CAD/CAM/DNC/CNC has become a key support function.
Since the early 1990s the vital link between design and machining has been performed using Pathtrace software and, as a result, System Technologies has progressively upgraded from its original PAMS off-line programming system to the latest version of EdgeCAM.
Components are designed using CAD and brought into EdgeCAM using EdgeCAM Solid Machinist for Parasolids.
Anthony English explains the background: 'Our machining facilities are principally a development tool so ease of use of any computer system is vital.
EdgeCAM is intuitive and is very easy to upgrade.
When we upgraded from PAMS to EdgeCAM a few years ago it was very straightforward, helped along by the excellent Pathtrace training course.
Although we offer CNC turning, our principal applications are milling based involving case work and mould tool components which are machined from solid material.
In those applications, EdgeCAM's incorporation of tools such as Verify, gives us confidence, especially when machining a new component for the first time.' System Technologies' major involvement is in the development of sonar and other electronic systems for use in harsh environments which are mostly taken through prototype, development to production assembly stages.
Among the products developed at Ulverston is the Tritech SeaKing range of high resolution side scanning sonar.
This sonar is much in demand for sub-sea exploration purposes.
The company also produces echo sounders.
Anthony English explains: 'While the seal project was an out and out special, our devices are used by a variety of end users ranging from fishing vessels to salvage firms, oil exploration companies and the military.
Most devices also contain sensitive electronics.
One of the problems we have, is that these electronics have to operate in very harsh and hostile environments.
We therefore have an ongoing requirement to develop customised IP 67/68 enclosures for surface use, pressure vessels to protect the sonar equipment at depths up to 4,000 metres and withstand 6,000 psi, as well as the appropriate underwater connectors.' Components are designed in-house on CAD for manufacture in a range of corrosion resistant materials.
A considerable amount of aluminium is machined but plastics including acetals and polyurethane, which is machined and moulded, are also used, alongside a limited amount of stainless steel.
As well as aluminium parts for direct use, the company also has a requirement for short run plastic mould tooling.
'While machining tolerances are not desperately tight; bores with sealing surfaces need to be within 0.02 mm.
Flatness is also an important.' Lathes tend to be programmed at the machine while EdgeCAM is used for milling programs.
Anthony English maintains that the milling can be quite involved and it uses its surfaces capability to generate complex profiles for pressure vessels and to create an element of streamlining when required.
A lot of our work, particularly mould cavity machining draws on EdgeCAM's 3-D machining capabilities though we also perform a considerable amount of 21/2-D work as well.
A significant number of jobs are never to be repeated, so program optimisation isn't a priority; that said, machining cycles still need to be accurate and concise.' Installation of EdgeCAM was a logical progression for System Technologies and the company sees itself as a long term user of the software.
It is intending to move its design onto a parametric solids based CAD system in the near future, and one of the stipulations will be compatibility with the Pathtrace System.
'We're very satisfied with EdgeCAM's performance,' Anthony English concluded.
'Our experience demonstrates how very competent the software is and we have, to our advantage, found it to be a well supported product.'