When John McNab and Ashley Mizen (two engineers who had once been colleagues) found that they were working ‘round the clock’ in their respective posts, they decided to set up their own machine shop — one that would be based on automated production to “minimise the required man-hours”.
This approach to their new business — Andover-based Multax Engineered Precision — resulted in the first machine being a 10-pallet five-axis Mikron HSM600U.
Having won its first order (for 134 stainless-steel pivot blocks for a marine customer) before this machine was delivered on 19 December), the Multax partners had to ‘hit the ground running’.
Just before Christmas, they also bought HyperMill CAM software from Open Mind and contacted Dave Cleeve from Tamworth-based Industrial Tooling Corporation Ltd (
www.itc-ltd.co.uk) for cutting-tool support.
Multax director and production manager John McNab said: “In the first month, we were under pressure to get the machine up and running, as we had to get our first order out. We needed the support of reliable and trusted suppliers — and effective solutions.”
The stainless-steel pivot blocks started as 146mm-long 10in-diameter billets weighing 50kg; once finished, they weighed just 15kg. The company calculated that each part would have a machining time of 8hr, justifying the
investment in a multi-pallet machining centre capable of ‘lights out’ operation.
“We knew that we had to achieve unmanned machining or risk our first job taking most of our capacity, so we needed cutting tools with reliable, consistent and efficient performance. ITC delivered a complete package that allowed us to achieve this.”
The ITC solution included a variety of Widia indexable-insert tools and drills, as well as the company’s UK-manufactured solid-carbide end mills. To take the complex stainless-steel components from a raw billet to just 15kg, ITC recommended the Widia M200-series button end mill.
This six-insert 50mm-diameter tool was used to rough-machine the pivot blocks, while a 35mm-diameter M200 was used to helically interpolate a large bore through the parts. ITC recommended a 50mm-diameter Widia M1200 45deg face mill for finishing the external features.
“We have 50 tool positions on the Mikron. We have one 35mm-diameter tool for helical milling the bore and three 50mm button-type milling cutters for roughing. We have set the tool-life parameters at 2hr per tool to ensure that we achieve consistent and reliable performance, although the inserts generally last much longer.
The M200 inserts have six edges, while the double-sided inserts in the M1200 cutter have 12 edges. This makes these inserts particularly cost-effective; so after one indexable tool has completed 2hr of machining, the next tool is used. At a cost of about £4 per insert for more than 16hr of rough-machining stainless steel, there is little point trying to stretch tool life.”
As well as the indexable tools, Multax is using the Widia VariMill 2 — a 20mm-diameter six-flute solid-carbide end mill for machining the side walls of a 90mm-deep slot in the marine components.
This roughing tool is followed by 4mm- and 12mm-diameter ball-nosed VariMill tools that are held in Widia extra-long slim-line tool-holders for ‘scanning the chamfer’ and removing the root radius at the base of the slot.
Multax is also using 6-, 12- and 16mm-diameter four-flute VariMill end mills for other rough-machining operations on the pivot blocks.
As a start-up business, Multax has also taken full advantage of the Widia Voucher Promotion Scheme. This offers customers heavily discounted prices on tool-holders when they buy a new machine tool.
“ITC’s voucher scheme has saved us over £10,000 when tooling our Mikron and the Bridgeport machine that we recently added. We’ve bought more than 60 collet chucks, as well as face-mill arbors and extensions for extra reach.”