Crushing stone with stone: Bryan Bartley, Jim Macdonald and the Barmac crusher

{{image2-a:r-w:300}}The Barmac rock crusher has, over the course of nearly 50 years, proved revolutionary. Originally called the Macdonald Impactor, it uses two basic concepts: rocks crushing themselves when they hit each other, and a layer of rock to protect the metal surfaces of the machine.

Jim Macdonald developed the idea during the 1960s, and by 1970, when he and Bryan Bartley first met, had a prototype crusher working successfully. He had not, however, managed to arouse much interest in the quarry industry until Bryan persuaded his employer, the Winstone Group, to build a machine in its workshop and test it at the Hunua Quarry in south Auckland.

At an early stage in its development the use of tungsten carbide inserts, salvaged from used rock drill bits, extended the replacement time of rotor tips from two and a half hours to six weeks. This also reduced operating costs by some 40 per cent, making the machine more commercially viable. Continuing experimentation led to the development of the Duopactor, a dual feed machine that used small stone fed through the rotor to break up larger stone fed directly into the breaking chamber, allowing material larger than 60mm to be processed.1

A cascade version, in which the same sized stone is fed into both the rotor and breaking chamber, substantially increased the production of fine material for no increase in energy consumption or wear on the machine. One of the other advantages of the Barmac crusher is its ability to produce cubical chips from hard stone, such as that quarried at Kiwi Point, in the Ngauranga Gorge, near Wellington, where Jim Macdonald developed his prototype.2

{{image3-a:r-w:300}}Rather than manufacture the machine themselves, Jim and Bryan formed Barmac Associates to licence production in New Zealand and overseas. Keith Niederer, an early Auckland licensee, achieved something of a breakthrough in 1976 when he sold two machines to WA Stevenson and Sons’ managing director Sir William Stevenson, opening the way to acceptance by other quarry operators. By the 1980s Niederer and other Barmac licensees had opened up markets in Australia, Japan, the US, the UK, South America, South Africa and Asia, and extended into Europe in the 1990s.

Sadly, after more than 40 years of manufacturing Barmacs in New Zealand, the machine’s current owner Metso Group (formerly Nordberg, based in Finland) closed down its manufacturing plant at Matamata in December 2013 and shifted production offshore. Metso first reduced the scale of its operations there in 2008 due to what the company described as “a weakening in demand for its products and services”.3


So who were these two men who developed such a remarkably successful, yet fundamentally uncomplicated, machine that now enjoys a worldwide market?

Jim Macdonald began his working life as far removed from quarrying and engineering as could be imagined. Born in Wellington in 1921, he began his working life in 1937 as an apprentice optician, before joining the Bank of New Zealand in 1938. A keen yachtsman and swimmer, he also joined the New Zealand division of the Royal Naval Volunteer Reserve that year as an ordinary seaman.

Promoted to able seaman and mobilised on the outbreak of war in 1939, Jim served as a gunner on armed merchant ships carrying phosphate from Nauru to Australia. Following selection as a potential warrant or commissioned officer, the navy sent him to Britain for training at HMS King Alfred, a “stone frigate”, formerly the Hove Marina at Brighton. There he passed top of his course in May 1941 and trained as a Coastal Forces officer, before joining a motor torpedo boat (MTB) squadron at Felixstowe on the Suffolk coast.

{{image4-a:r-w:300}}Jim soon distinguished himself, being awarded the Distinguished Service Cross (DSC) following an action in which he organised and carried out the rescue of injured crewmen, including his skipper, and the salvage of his badly damaged MTB. In his spare time Jim developed a torpedo sight that improved the accuracy of his flotilla and an engine silencer that enabled his MTBs to get close to the enemy without being detected. He earned a bar to his DSC in July 1943 and, although only 21, became the senior officer of the 21st MTB flotilla the following September, holding that position to the end of the war. Promoted to lieutenant the day after he turned 22, he went on to earn a second bar to his DSC.

Jim received the Distinguished Service Order in September 1944 following attacks on two German convoys on the night of 4 and 5 July. After similar successful actions later that year he was twice mentioned in dispatches and promoted to acting lieutenant commander, becoming at the age of 23 the youngest officer with that rank in the Royal Navy and the most highly decorated New Zealand naval officer of the war.

In 1946 Jim returned to Wellington with his wife Evelyn (nee Mathieson), formerly a third officer in the Women’s Royal Naval Service, whom he married in Aberdeen at the end of the war. He joined the water and drainage division of the Wellington City Council, studying civil engineering part-time at Wellington Technical College and Victoria University College.

His engineering interests later extended to quarrying, particularly the Kiwi Point quarry in the Ngauranga Gorge, roadworks and rubbish disposal.

As Wellington City Engineer, Jim also chaired the council’s airport development committee and maintained his wartime inventiveness, leading to the development of the Macdonald Impactor, later to become the ubiquitous Barmac crusher.

Following Jim’s death in 1982 after a short illness, Barmac Associates established the annual series of Jim Macdonald Memorial Lectures, which continue to play an important role in the New Zealand Institute of Quarrying’s education programme.4


{{image5-a:r-w:300}}Bryan Bartley began studying civil engineering at the University of Auckland in 1949, graduating BE in 1951 and taking up a position in the engineering department of the Auckland City Council. In 1954, he joined Winstone at its Lunn Avenue quarry. The job involved determining the extent of the remaining stone reserves in the quarry and finding other potential sites around Auckland to take its place when it was depleted. On his recommendation, the company purchased a small quarry and surrounding land at Hunua, south Auckland. Opened in 1961, Hunua continues to be the company’s main quarry in the region.

That same year Bryan moved to Malaysia to work as quarry engineer for Gammon Malaysia, which had the contract to build Kuala Lumpur airport. The company decided, however, not to open a quarry and in 1963 he returned to Winstone as a quarries engineer, later becoming general manager of the company’s central engineering division, until he retired in 1985.

It was as Winstone’s general manager that Bryan first met Jim Macdonald in 1970 and proposed the construction of an improved version of the Macdonald Impactor using tungsten-tipped rotor blades. When that proved successful, Jim offered Bryan a share in the business and, with the blessing of both Winstone and the Wellington City Council, they took out a joint patent on the machine. As their employers, both the council and Winstone generously waived any rights they might have to the patent. The council was only too happy to receive in return a machine that solved its quarrying needs, while Winstone did not have to pay royalties on any machines it obtained.


In the meantime, Bryan had, in the early 1970s, joined the New Zealand branch of the Institute of Quarrying (IOQ). He found that whereas in the UK the Institute had been something of a gentlemen’s club where quarry managers discussed business over golf and whisky, in New Zealand the members stood in their own right, with membership of the IOQ setting the professional standard in the quarry industry.

In the course of promoting the Barmac crusher on several trips to the UK over a six-year period, Bryan came to know IOQ members there. After serving as the chairman of the New Zealand branch from 1987 to 1989, he was invited to become one of the Institute’s international vice-presidents and then served as its last international president in the 1990s, just prior to various overseas branches becoming fully independent.

By that time, the international presidency had become, in Bryan’s view, largely a figurehead role, with the work of the Institute being conducted by a board and staff. His most important function was attending the annual ladies’ nights. The formation of independent overseas branches of the Institutes followed from a report he was asked to prepare on reorganisation around the world. He found that a degree of friction had arisen between the parent body and some of the branches, particularly over levies going to the UK.

Initially Bryan’s report had been stonewalled by the Institute because he had not produced what it had hoped for. But “they came around eventually” and the branches gained full independence. The international presidency has since been replaced with a biennial meeting of the presidents of each of the independent IOQs.


Over the years Bryan developed very clear ideas about the value of the quarrying industry to society. “Look at Auckland city,” he said. “Eighty per cent is built from aggregate in one form or another. The quarry industry provides all of the fundamental material for constructing buildings and infrastructure like sewerage and electricity generation. For quarries it is 50 per cent base course, 25 per cent seal, with the other 25 per cent going into concrete.”

The quarry industry also reflected the growth of the New Zealand economy in the years since the formation of the New Zealand branch of the IOQ. In the 1960s annual quarry output amounted to five tonnes per head of population, increasing to eight to 10 tonnes by 2011. At the same time production costs had gone up, particularly when quarries close to where their products were needed had to close down due to urban development or environmental sensitivity. The more distant a quarry was from its end users, the higher the transport costs were that fell on the ratepayer.

Also, the environmental effects of trucking over longer distances were often greater than those of the quarry itself, particularly following the introduction of modern blasting techniques and environmental mitigation measures. Bryan saw the biggest environmental challenge to the industry as being the need to overcome the “natural equals beautiful, man-made equals ugly” argument.

“It takes an experienced quarryman to appreciate the true beauty of a well developed quarry face,” he once remarked.
Along the way Bryan received a number of awards recognising his contribution to the industry and his services to the community. In 1979 he and Jim Macdonald received the UDC Finance Inventors’ Award for the Barmac crusher, being judged first equal with the inventor of a freezing works carcase barcode scanner. In 1989 he received the first ever Caernarfon Award, originally endowed by the north Wales branch of the IOQ and named after the town where the first Institute meeting took place in 1917. Presented in the form of a Welsh slate pendulum clock, the award is for the best conference paper presented anywhere in the world in the previous year.

Bryan’s many years of service as a member of a variety of community organisations received recognition in 2000 when he became an Officer of the New Zealand Order of Merit, of which there are only 80 at any one time. After his retirement in 1985 Bryan also kept up his interest in machinery and innovation, including the development and manufacture of feathering propellers for racing yachts, which, like the Barmac crusher before them, have penetrated overseas markets.

Bryan Bartley passed away on 24 March, 2015. He is survived by his wife of 43 years Elaine and his extended family of three children, four step-children and numerous grandchildren and great-grandchildren.


Bryan Bartley – a true friend and gentleman

{{image6-a:r-w:300}}IQA Honorary Fellow Fred Reid pays tribute to Bryan Bartley, whom he counted as a close work colleague and good friend.

I first met Bryan Bartley when I joined the Winstone Group in 1966. For the next 17 years I was privileged to work with him on a multitude of activities.

In his capacity as the general manager of Winstone’s Central Engineering Services Division, we communicated on many aspects of a general quarrying nature.

Bryan was stationed in the company’s head office in Auckland, while I was based at the offices in Winstone’s Lunn Avenue Quarry at Mount Wellington.

At the time, the Lunn Avenue Quarry was the largest quarry in New Zealand (with an output of two million tonnes per annum). It was situated in the middle of Auckland and surrounded by high tech industry, a large commercial centre, a university, a premier golf course and a ridge line of expensive homes to the rich and famous, with an unimpeded view of the quarry. Blasting occurred three times per day to reduce blast sizes, and five monitors would be situated at sensitive locations around the quarry to record impact noise and overpressure. Bryan had an influence on the equipment and procedures deployed to afford these measurements. He also managed the activities of the Winstone laboratories.


Bryan and local electrician Noel Curtis invented a blast machine that was housed in a steel trailer, and – positioned behind the blast – it was connected to each detonator in a simple series circuit. The blast machine comprised of a drum with attached contacts and a variable speed drive motor, powered by two 12-volt batteries. The battery power allowed the drum to turn at a determined speed and provide a delay sequence from 200 microns per second through to instantaneous.

The subsequent headlines in the New Zealand Herald erroneously read along the lines of “Winstone develops machine gun blast system!”

Bryan had input with the extraction and processing procedures of three sand plant operations dredging sand from the Waikato river, south of Auckland. We once trialled a Barmac there with an eight foot (2.4m) diameter rotor, in an attempt to destroy the pumice and charcoal resident in the sand. The unit was started direct on-line and a high pressure hose was directed into the unit to provide rotation before dropping the starter switch. This was not a success and caused a blackout in the Waikato area. We did not proceed with this!

It was always disputed whether it was Russell Searle from Mole Engineering or Dick Hassed of ICI New Zealand who was foremost in establishing the NZ branch of the Institute of Quarrying. Bryan was present at the inaugural meeting of the NZ branch. He was a solid supporter of the Institute and he and his wife Elaine were a big presence at every annual conference.


Bryan’s big contribution, of course, was his introduction of the Barmac into the quarrying industry, and identifying the importance of particle shape to optimise the performance of all construction materials. This enabled quarry producers to provide cubicity to the smallest particle and create the difference between a by-product of the crushing process – “crusher dust” – and converting it into a high performance “manufactured sand”.

I left Winstone in 1983 as the operations manager for its NZ and overseas operations to join the Fletcher Challenge company Firth Industries, and moved to Wellington. One of my treasured possessions is a letter of reference Bryan wrote for me on leaving the Winstone Group.

I was a foundation member of the NZ branch of the IOQ and for many years sat on the NZ executive council of the Quarry Masters Association. I also served a term as chairman of the NZ branch of the IOQ.

Before departing NZ to take up a general manager’s position with Boral in Sydney, I travelled to Auckland en route. Bryan and Elaine had invited my wife Vicki and I to stay over for a meal prior to our departure from Auckland. We were ushered to a room upstairs to freshen up and asked to join them in the dining room 30 minutes later. We descended the stairs to be greeted by the entire executive of the IOQ and the Quarry Masters Association, whom they had invited to give us a surprise formal farewell.

Bryan Bartley was always a perfect gentleman. A dedicated family man, he had a very disarming personality, an almost perpetual smile. He enjoyed a beer but was a man who never swore and he was an embellishment to any company he chose to engage. He spoke with authority on many subjects – his foremost, of course, being the Barmac and its latest development, but also his folding yacht propeller.

It is a common human failing to not pay sufficient attention to our dear friends and appreciate their true worth until we no longer have that privilege.

He will be fondly remembered and sadly missed by friends and associates globally.

This story originally appeared in Profiles in Stone: Stories from New Zealand Quarrymen, compiled for the Institute of Quarrying New Zealand Inc by Louise Foord and Neil Clayton, 2012 (ISBN 9780473215842). It appears in Quarry with kind permission. For more information about the book, visit


1. Bryan Bartley, interview by Louise Foord, Auckland, 3 August 2011; Metso Minerals and Carl Walrond, ‘Rock, limestone and clay’, Te Ara – the Encyclopaedia of New Zealand. (updated 2-Mar-09).
2. George Cunningham, interview by Louise Foord, Matamata, 5 December 2011; Jim Hunter, interview by Louise Foord, Dunedin, 27 March 2012.
3. McCarthy K, Campbell-Hunt C. Svedala Barmac: A case history. CANZ Research Programme, Victoria University of Wellington, May 2001, 14-16; Metso Corporation Press release, November 27, 2008; Personal communication, Bryan Bartley to Neil Clayton, 3 April 2012.
4. Dennerly PY. Macdonald, George James – Biography. Dictionary of New Zealand Biography. Te Ara – the Encyclopaedia of New Zealand (updated 1-Sep-10).; Gerry Wright, North Sea Warrior, (New Plymouth: Gerry Wright, n.d.), passim.
5. Bryan Bartley, interview by Louise Foord, Auckland, 3 August 2011.

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