Leaving the comfort of employment and starting a business is not a decision to be taken lightly, but it is one that two aerospace engineers took when founding GD Precision, re-mortgaging their homes to do so.

Some 17 years later, it is apparent that the decision has paid off.

Now operating from a 4,400ft² facility in Arundel, the company has seven staff, a host of CNC machine tools from the likes of Mazak, XYZ and Dugard, and a list of clients from the F1, aerospace, transport and medical industries.

Like most sub-contract machine shops, GD Precision is continually striving for cost reductions and greater efficiency, along with enhanced productivity and component quality; helping the company achieve these ambitions is the Tamworth-based cutting-tool supplier Industrial Tooling Corporation Ltd (ITC) (www.itc-ltd.co.uk).

Recalling life before a ‘cold call’ by ITC sales engineer Dave Cleeve some 10 years ago, GD Precision director Dale Buckthorpe said: “In the early days, we were conscious of our spending and watched every penny.

"We would buy low-cost tools from a variety of suppliers and would continually have them re-ground, which in hindsight was a false economy.”

"Mr Cleeve suggested we use tools that cost considerably more than the ‘cheap’ ones we were using. We took some convincing.”

Gary Short, fellow director and head of GD Precision’s milling department, said: “Mr Cleeve reviewed our workload and proposed that we try ITC’s 3081-series square-end three-flute solid-carbide end mill.

"At the time, we were using 20mm-diameter ‘ripper’ cutters from another supplier to machine an aluminium component with the full 20mm width at a depth of 1/2xD and a low feed rate.

"As suggested, we applied the 3081 cutters at full flute depth, with smaller cuts but at speeds and feeds that were markedly higher than we had been using. Although we were sceptical at first, we immediately achieved cycle time reductions of 50%.

“Moreover, the surface finishes were considerably better, and tool life was anything from four- to five-times better than that achieved by our previous tools.

“We instantly appreciated the benefits of paying more for tools from a premium-brand manufacturer — and recognised that the technical expertise offered was invaluable.”

Further purchases

The success of those initial trials resulted in GD Precision buying a ‘full line’ of 3081 end mills — ranging in diameter from 6 to 20mm — for applications ranging from roughing to finishing.

Mr Short said: “The 3081-series tools are general-purpose aluminium end mills with a high helix, and we now use them for just about every task.

“We have recently been machining dental mould tools, and the 3081 cutters are achieving 70-plus hours of trochoidal machining on high-grade HE15 aluminium.”

With the ITC 3081 cutters the tool of choice for all aluminium machining tasks at GD Precision, the directors had the confidence to trial further ITC tools — including Widia VariMill TiAlN-coated four-flute end mills for machining stainless steel and exotic materials.

These cutters proved every bit as successful on challenging materials as the 3081 cutters had proved on aluminium. Mr Short added: “It took us a while to adjust to the VariMill’s high speeds and feeds; we are now machining jobs faster, but with smaller cuts, and pulling 30-40% less spindle power.

“ITC also influenced the evolution of our machining strategies, including trochoidal milling.”

For the high-speed roughing of challenging materials, GD Precision is now using ITC’s 6051-series six-flute centre-cutting end mills.

“The long-length 6051 cutter we use has a 60mm flute length that allows high material removal rates with excellent reach characteristics.

"There is very little depth in the flutes of the harmonic 6051-series cutters; this increases strength and eliminates vibration, enabling us to run at 3-4m/min. On materials like stainless, we are machining at a feed of 0.2mm per tooth using the full 60mm flute length.”

Spindle interface

When GD Precision recently added a second Dugard Eagle 1000+ machining centre — one with a BIG-PLUS spindle interface — Mr Cleeve recommended that the company took full advantage of the face and taper contact this offers and buy a BIG Kaiser Hi-Power milling chuck, saying it would improve rigidity, concentricity, tool life, surface finish and precision, while also minimising vibration.

Mr Short said: “Although this Dugard machine is very robust and stable, we were struggling to use ITC’s recommended speeds and feeds.

“As soon as the BIG Kaiser Hi-Power milling chuck was used, we knew the weak link had been our old milling chucks.

"With the BIG-PLUS milling chuck, we can reach the recommended speeds and feeds with no chatter and vastly improved surface finishes; we have also improved tool life by at least 20%, upped our cutting parameters by over 25% — and the run-out is well below 5µm.”

“The BIG-PLUS milling chuck allows us to run 12- and 16mm-diameter VariMill tools with a trochoidal strategy on stainless steel at a cutting speed of 100m/min and a spindle speed of 2,000rev/min.

“This has resulted in a significant cycle time reduction on dental mould tools — from 12min to 6min 45sec.”

There is one habit the company has not dropped, as Mr Short highlights: “We still collect boxes of used end mills.

The difference now is that with ITC being a UK manufacturer, we are returning the solid-carbide cutting tools to the OEM for re-grinding.

ITC has full details of the geometries of all its tools — and the re-grinds are done on the same machines that originally produced the tools.

“This means that we get our re-ground tools returned in an ‘as new’ condition at a fraction of the cost of new tools.”