The benefits to Aerolux and its customers are considerable, as parts are quicker and less expensive to make by milling than by welding. Managing director, Ken Metcalfe, says that a fridge door and frame, for example, would require 10 to 12 hours in the fabrication shop whereas they are machined on a Hurco VMX 42 in less than half the time. A further advantage is that components are more repeatable than when welded, which introduces distortion, so parts assemble more accurately from batch to batch. Moreover there are no welds to fettle, so a lot of finishing has been eliminated.
Aluminium frame for an aircraft refrigerator
The move towards CNC machining has far-reaching implications on the design of Aerolux products. It is possible, for instance, to mill sections down to 2 mm, much thinner than can be fabricated, resulting in reduced weight. Another positive change has been to machine on the Hurcos, the groove that accepts the oven door seal instead of having to use two frames, one inside the other, to achieve a similar, heavier result. Lightness is of key importance to aircraft operators, which are always looking to maximise fuel efficiency.
Mr Metcalfe has plans for redesigning many other parts and predicts that most of the components that go into the company's products will be CNC machined rather than fabricated within a year or so. He has also adopted a similar policy for turned parts, many of which now go onto CNC lathes.
Until the late 90s, practically everything was fabricated at the Blackpool factory, mainly from aluminium for lightness, stainless steel for hygiene, and expensive, heat-resisting plastics approved for aerospace applications. The plastics were designed out of the ovens, partly due to the high price of the material and of the vacuum forming tools needed to make the oven doors, and also because the plastic was prone to crack when machined.
Close up of refrigerator frame on the VMX42
Once the VMC was installed, other parts such as mounting rails for expresso machines were soon produced from the solid as well, eliminating buying-in castings and machining them by hand on a turret mill. So successful was this exercise that Aerolux now supplies these components to its competitors. Fridge frames were next onto the Hurco, followed by rear mounting brackets, and the migration of parts from the fabrication shop to the CNC machining section has continued ever since.
Close up of airline coffe maker being machined
A typical order from one of the major airlines might result in batch sizes of 25-off doors or frames and 50-off mounting rails, but it can be as low as one-off if the appliance is to be used in a custom executive jet. Ease of programming at the machine has therefore been of considerable help to Aerolux.