XYZ easy to use CNC Machining 2

From an early age traction engines have played a major role in Richard Scourfield’s life, his admiration for the craftsmanship of bygone times influencing his decision to become an apprentice engineer. Although he spends much of his time restoring examples of this alternative to the heavy draught horse, he is adamant that it remains a hobby and separate from his day to day role in charge of subcontractor Bartlett Engineering Co.

Having spent several years in the power generation industry, it was his father’s ill-health that led to Richard and his wife Kay buying the family business some 26 years ago. At that time Bartlett Engineering, having begun as a vehicle body builder, was primarily a fabrication shop offering ring rolling, section bending and plate rolling. Precision machining was introduced to broaden the company’s appeal, and it has since succeeded in this objective with, for example, the Sageston, South Wales, company providing 24 hour, seven days a week emergency cover for local refineries and gas processing plants. Much of this is maintenance and repair work involving reverse engineering of damaged or worn parts.

The subsequent introduction of CNC machine tools to what is essentially a job shop environment has resulted in a higher hourly charge-out rate but, says Richard Scourfield, this is more than offset by significant reductions in cycle and delivery times. “Careful investment in CNC machinery has made it possible to not only economically produce large production runs but also to be cost-efficient on smaller production runs and one-offs.”

However, he admits that his commitment to traditional engineering skills did delay the transition to CNC machining. The impetus for change came with an invitation and subsequent visit to XYZ Machine Tools’ 21st anniversary celebration in 2005, and a demonstration of the plain English prompt programming of the ProtoTRAK CNC system. “My mind was made up there and then that I was going to buy one of these machines. It’s a decision that I wish I had made years before and it is a decision that I have not regretted since.”

Despite Richard Scourfield’s insistence that traction engines are a hobby and not a commercial activity, Bartlett Engineering does have a specialist workshop on-site for the repair and construction of steam boilers and engines ranging from half-size models to full-size locos and traction engines. So, inevitably, replacement parts are made in-house for fellow enthusiasts as well as for his own projects. “We’ve made lots of pins, con rods and so on using our XYZ machines, often working from original drawings. But while we do use modern materials and methods of construction, the objective is always to remain true to the traditional look and feel. This takes time, which is why my latest project – the restoration of a 1909 Charles Burrell & Sons traction engine ‘Joe Chamberlain’ – has taken several years to complete.”

Bartlett Engineering’s most recent capital investment is a 7.5 kW/2500 rev/min XYZ ProTURN SLX 425 1250 mm between-centres CNC/manual gap bed lathe, bought to replace an earlier model in accordance with the company’s policy of updating on a regular five-year cycle. It joins an 11 kW/1800 rev/min ProTURN SLX 555 1750 mm between-centres CNC/manual gap bed lathe and a 3.75 kW/5000 rev/min ProtoTRAK SMX 3500 CNC/manual bed mill that has full CADCAM/DXF capability.

“We went to XYZ originally because we didn’t want to get into G and M code programming. We wanted simple conversational programming that could be used by everyone from older generation manual machinists to young people with limited machining experience. I had one person who was pretty sceptical of CNC and how it would assist us, but it took just ten minutes with the ProtoTRAK control to convince him of the benefits. As for me, it did take a little while to get into the mindset of telling the control the shape I wanted to end up with and then working back to what I wanted to make it from, but the training provided is brilliant.”