Specialised fastener manufacturer's CNC sliding-head automatic lathe is slashing production times and providing the capability to quote same-day order turnaround if necessary.
One of the UK's leading subcontract manufacturers of specialised fasteners and other turned parts, Vaughan Jones in Wetherby, Yorkshire, has invested in a third Star sliding-headstock lathe to extend its pursuit of one-hit machining to components of up to 32mm diameter. The Star SV-32 lathe has taken over from fixed-head turning of complex parts, slashing production times and providing the capability to quote same-day order turnaround if necessary. Vaughan Jones' joint managing director, Roger McGlone, cited the case of a typical socket screw which previously required five separate operations: blank and turn roll thread diameter; face, centre and drill; broach; clear broach chips from the bottom of the socket; and thread-cut or roll.

The accumulated cycle time total was between 4 and 8 minutes, depending on component size, and lead time from order to delivery used to be one month.

The same job is now completed in one visit to the twin-spindle, multi-axis Star SV-32 in a cycle time of 1.5 to 2 minutes and additional operations such as head drilling can also be carried out in-cycle.

Not only is immediate turnaround of urgent orders possible, but economic batch size is also reduced and so too is the amount of work-in-progress (production inventory) on the shop floor.

Vaughan Jones started its investment in sliding-headstock machines in 2001 with the installation of a Star SR-20R lathe of 20mm bar capacity, followed in 2003 by a second, identical machine.

Continued Hornby, 'We had one hundred or so cam autos and plug-board machines operating 10 hours a day and basically we were getting nowhere.

We decided on a rolling programme of replacing these outdated lathes with sliding-headstock CNC models, having satisfied ourselves that this was the way forward rather than going along the fixed-head route, which would have curtailed our one-hit machining strategy.

Very few of our components need a second operation now.

Hornby said: 'The other considerable benefit of installing the Stars was the advent of year-round 24h operation, trebling available hours compared with a manually-operated auto.

Moreover, the majority of productive hours on a Star are minimally manned, resulting in labour cost savings as well.' The latest Star SV-32 has the capability to deploy 80 tools in the working area whereas even with diversification into more complex parts such as bar-turned nuts and couplings, only six or seven tools are currently used to produce any particular component.

Likewise, the capability of the Star to produce special features such as off-centre and angled holes around the circumference or in the end face of a component are scarcely used.

Hornby's reason for installing this machine was, however, not only to expand Vaughan Jones' fastener range but also to diversify into the subcontract production of more complex parts, a service which he is actively marketing both within and outside his customer base.

Materials vary widely and are often difficult to machine, hence the addition of high-pressure coolant to the latest Star lathe.

They include high-tensile, stainless and mild steels, brass, bronze and nickel alloys as well as aircraft materials and plastics.

Manufactured to international standards and customers' specifications, Vaughan Jones' high quality products find their way into diverse industries including defence, aerospace, mining, medical, telecommunications, machine tools, tooling, motorsport and automotive engineering.