One of the leading 2012-season Formula One teams is now pounding the world’s racing circuits with components on board that have been produced on a Citizen CNC sliding-head mill-turn machine by a ‘fledgling’ sub-contract precision machinist that set up just over three years ago — with a single pre-owned Citizen L20 CNC sliding-head turn-mill centre — in a converted cow-shed near Luton.
Soon after setting up in April 2009, Sub-CNC installed a fixed-head two-axis chucking lathe with a 44mm bar capacity. This was followed by a second Citizen — a larger-capacity L32 — then by a second L32 the same year, to meet the fast-growing order book. With demand from established customers continuing to increase through 2010 — plus a growing level of word-of-mouth recommendations adding new business — machining capacity was running out fast, and the two partners —Yian Stavrou and George Dingley— decided to buy Sub-CNC’s first new machine.
The installation of the Citizen A20-Vll in the same month as the second L32 meant that they had by now out-grown their original premises, so they moved to a new machine shop in nearby Dunstable.
The partners felt that the Citizen A20 purchase and the factory move gave them “breathing space to re-align the business for the future. Existing customers were not only adding to our order book but were also beginning to make it very clear that they wanted Sub-CNC to supply larger-diameter bar components as complete packages, rather than having to deal with ‘cherry-pickers’ who could — or would — only perform certain tasks,” said Mr Dingley.
Further developments
Not wishing to miss opportunities or risk customers looking elsewhere, the partners decided at the close of 2011 to order the machine that had really impressed them at a Citizen Machinery UK Open House — not another sliding-head machine but the newly released Miyano BNA-42MS. This is a six-axis fixed-head turning centre that can also be used for chucking work.
However, 2011 was not only a time for investment in new machine tools; Sub-CNC also implemented some major changes. The company appointed Nick Walker as general manager to cover sales, customer interface and purchasing. It also appointed Karen Condon as accounts manager in April — and took on another machine operator the same month. In June 2011, James Collins was employed as an apprentice direct from school to learn CNC machining and spend one day a week at college.
Mr Stavrou said: “We know how we want the business to be run, but it is difficult to get people with the right skills, as well as the interest and willingness to work in our particular way; so we decided to take on an apprentice as a longer-term solution.”
Further investments made last year to move the business forward and help improve margins and productivity include a non-contact measuring machine and an ultrasonic component-cleaning system. Sub-CNC also introduced in-house anodising and surface treatment as part of the service it offers.
With the help of Mr Walker, last November the company obtained ISO 9001 — at the first attempt — without a single recommendation for change or improvement listed.
Mr Dingley said: “Both Yian and I have been so focused on tooling up for new work that we could have never paid sufficient attention to developing systems. However, last year we were able to set up fully functional quality control and production control/scheduling systems — and provide a stock-holding service with next-day delivery, along with full traceability records.
“Mr Walker’s background in sales helps to develop key accounts, such as the F1 contract, which is far from being simple work; the two electronic enclosure components, which are assembled by the racing-car customer, have 6µm tolerances on bores and outside diameters.
“However, because these parts have to be anodised, initial prototyping involved some experimentation on the Citizen A20 to obtain a pre-plating process size. Here, the level of accuracy and repeatability we obtained from the Citizen A20 gave us total confidence, once we were able to establish the process size and then work effectively between the tolerance levels we had determined.”
An initial 20 sample parts, followed by an in-depth supplier analysis by the racing-car customer, resulted in a contract for 800 of each part to be delivered in batches of 200 components.
Broad customer base
The progressive build-up of Sub-CNC’s customer base to its 25 current active companies reflects a good spread of sectors covering aerospace, defence, electronics, marine, medical, metrology, hobbies, fittings and motor-sport. Around half of the order book is repeat business in batches that range from prototype and development work to contracts for 70,000 parts per month, although the average batch size tends to be around 1,000 parts.
Materials vary from non-ferrous and plastics to difficult-to-machine grades of stainless steel. The balance of orders keeps the two partners busy on the setting and prove-out of new work. Mr Stavrou says: “Our machine selection has been really important in our company’s growth. For instance, the Citizen A20-VII with its Streamline control and software has made a significant difference, allowing the machine to be set easily and quickly — very important to us, due to the need to be continuously setting new and often challenging work. For example, when we moved into the new building, we had an urgent order for 10,000 parts. We set the job on Friday and were sufficiently confident to run it part-manned over the weekend. By Monday, the order was complete.”
Mr Stavrou and Mr Dingley both had some 15 years’ experience of setting Citizen sliding-head machines before starting their own business. Mr Stavrou says: “We find that our background gives customers a lot of confidence, especially as we have continued to buy machines from Citizen and know how to get the best from them. That said, the decision to buy the Miyano BNA-42DHY was one of the most important steps in the development of the company. While we needed the larger 42mm-bar capacity, we also needed a machine that gave us the maximum productivity and flexibility for the investment.”
The Miyano has a 7.5kW main spindle, a 5.5kW secondary spindle, an eight-station turret with a ±35mm Y axis, and an all-driven turret that can be tooled to give up to 16 tool positions. As an option, Sub-CNC also ordered a Quad turning holder for the turret, giving it up to four turning tools on a single station. Furthermore, the BNA machine was the first model from Miyano to use Citizen’s Streamline control and software which, in addition to speed, provides Sub-CNC with programming familiarity. The pick-up size of the secondary spindle has been increased to 40mm (32mm is standard).