David Watt, owner of sub-contractor DW Engineering, has trebled the size of his business since the beginning of the decade, with most of that growth taking place last year (2018), which saw a doubling of turnover.

He puts this success partly down to winning contracts for machining batch sizes up to 10-times larger than before (orders are now frequently received for thousands-off rather than hundreds); these are largely undertaken using four Hurco vertical machining centres (VMCs).

New work in the electronics and gas detection sectors has been won, as well as in the resurgent oil and gas industry; about 80% of DW Engineering’s throughput is repeat business, and some of it has been retained since the company was formed.

A further contributor to increased turnover (and profitability) is the Adaptipath high-speed-machining software in the latest version of Hurco’s WinMax conversational control; this includes ‘novel routines’ for rest material removal, resulting in program cycles that are significantly faster — especially when pocket milling.

Established in 2005 in Blantyre, Scotland, DW Engineering used equipment supplied by High Wycombe-based Hurco Europe Ltd (www.hurco.co.uk) from the outset, with the purchase of a machining centre (nominally 0.5m-cube capacity) and two CNC knee-type mills.

A Hurco VM10 machining centre was acquired five years later, and these four machines were subsequently traded in for three of the machine tool builder’s latest VM10i VMCs (the first arrived in 2018, and it was joined by two more this year).

Additionally, there remains on the shopfloor a smaller Hurco VM1 with fourth axis (purchased in 2009), as well as a bar-fed Hurco TM8 CNC lathe that was installed in 2015.

Faster production

Comparing the performance of the nine-year-old VM1 with that of his three modern (and slightly larger-capacity) Hurco VMCs, Mr Watt referred to an aluminium housing (for an electronics industry customer) that he has produced in two operations on both types of machine.

“On the earlier model, running a previous release of WinMAX programming software that included Ultipocket milling routines, the total cycle time was 165min; that was before Hurco introduced Ultimotion software to control axis movements on its machines, without relying on hardware-based motion control.

“We now produce the electronics housing in 120min.”

Mr Watt says a major factor in this increase in efficiency is Adaptipath pocket-milling software, with its new rest-machining routines.

“The conversational pocketing feature is a module within Ultipocket in WinMax 10.

“This mirrors that used in high-end CAD systems, smoothing the motion of the tool-path, keeping the chip load between a user-defined maximum and minimum, improving surface finish and extending tool life.”

In addition to the two standard pocketing cycles involving inward and outward spiralling of the cutter, Adaptipath includes two extra rest-machining routines — zig-zag and 1-way — both of which involve alternate periods of climb milling.

The amount of material encountered by the cutter is controlled, often allowing a full depth of cut (rather than ‘peck level milling’) for higher metal removal rates.

Indeed, Mr Watt said removal rates can be as much as doubled.

Rest machining

“With rest machining, a larger-diameter tool than usual is used after roughing to remove most of the remaining unwanted material efficiently, followed by a finishing pass that automatically swaps the tool for a smaller-diameter cutter that can reach areas of the feature that the larger rest-milling tool was unable to access.

“This offers a six- to eight-fold speed increase compared with previous machining methodologies.”

Looking back at his company’s progress over the past 14 years, Mr Watt said: “The variety of materials we are asked to process is vast, ranging from stainless steels and mild steels through titanium, copper, bronze, brass and aluminium to PTFE, PEEK, acetal and nylon.

“Accuracies routinely achieved are ±0.1mm but some parts have drawing tolerances down to ±10µm.

“We have never needed a CAM system to prepare programs for the Hurcos, as their on-board conversational software is so powerful when it comes to creating the cutter paths.

“Moreover, there is no need for post-processing; and if any particularly complex geometry is included in a CAD model supplied by a customer, we use AutoCAD or SolidWorks to produce a DXF file that WinMax imports directly.

“The Hurco machines, which continue to evolve and improve, have supported our diverse work and underpinned our success.

“They are key to our ability to offer top-quality work, quick turnround and competitive prices.”