Formed in 1947 by Pat Hare, Bristol-based PJ Hare (Hare Presses) is now a leading UK manufacturer of hydraulic and hydro-pneumatic presses with forces ranging from 1 to 400 tonnes (
www.harepress.co.uk).
The company also supplies precision tooling for its products, which are used mainly by the automotive and food-packaging sectors, which account for much of the company’s business.
With sales growing and further export markets being targeted, the demand for machined parts is also increasing, with typically two presses a week plus tooling being produced.
Historically, PJ Hare’s in-house capacity was based on manual machining, but this was not sufficient to meet the company’s needs, so a high proportion of the work was sub-contracted.
Following a business review, it was decided to bring back in-house much of this machining work; and under the guidance of production engineer Konrad Nerc, this process was started with the purchase of a Doosan DNM 500 vertical machining centre, soon followed by an XYZ TC 320 LTY turning centre.
These investments in modern machinery meant that PJ Hare had to make a change in tooling technology, from using predominantly high-speed steel and morse-taper-shank drills on its manual machines to using the latest in indexable insert and solid-carbide tooling.
With components machined from a variety of materials, from mild steel and cast iron through to more exotic materials with hardnesses up to 50HRc, the company knew it would need help from a tooling supplier if it were to achieve its aims — particularly as these included moving away from the use of castings to machining parts from solid. The decision was taken to work with Sheffield-based WNT (UK) Ltd (
www.wnt.com).
Mr Nerc says: “In order to justify the investment in machine tools, we had to show productivity gains and keep cycle times as short as possible. Our use of Edgecam allowed us to develop efficient machining strategies.
We can also download CAD drawings of all the tools we use directly from WNT’s Web site; and behind that is a wealth of cutting data that has proved invaluable to us. We can also call on the support of our local technical sales engineer, Nigel Marsh, who worked with us in the early days, undertaking machining trials and helping us
get the best from our new machines.”
With the process of change well under way, Hare Presses is now using mainly WNT’s U-type indexable-insert drills, or the company’s WTX Change replaceable-head drills; the latter are greatly improving productivity, as the speeds and feeds used sit nicely within the power bands of its machines.
Milling is a combination of indexable WNT HFC high-feed cutters for machining small-diameter deep pockets, while WNT’s CCR milling system allows deep pockets to be machined in a single pass, thanks to its six-flute design and a geometry that gives excellent chip evacuation.
Hare Presses also makes use of WNT’s Exchange system of milling cutters; similar to the WTX Change drills, this allows the cutting head to be replaced by different sizes of cutter heads. These are also being used on extensions up to 250mm long.
As a result, tool-holding has been reviewed, and the WNT Centro P collet system is now the tool-holder of choice due to its high gripping power and accuracy. The investment in machine and tooling technology has allowed Hare Presses to bring back in-house over 70% of its machining requirement, giving the company much greater control over its production and quality.
Mr Nerc said: “The positive experience that we have had bringing work back in-house, combined with the service levels from WNT, gives us the confidence that we can continue to develop our in-house machining programme to meet the increase in business that we are experiencing.”