13 minute read
RUNNING REPORT
Below and below left: In the market for a new motor grader three years ago, Calum McCrae bought this high-spec John Deere 672GP model off Deere’s show stand at Bauma 2019.
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FIRST DEERE IN DECADES
David Wylie travels to Argyll to see how A&L McCrae’s grader is standing up to the harsh realities of winter working in Scottish forests
ounded by Alistair and Linda McCrae and now run by their son Calum, A&L McCrae is a long-established fi rm operating throughout the west coast of Scotland. They work across many disciplines, including building and maintaining forestry roads, civil engineering, general contracting, haulage and plant hire. In addition, they source and process local rock for their contracts, which is generally blasted or broken out of borrow pits, or from their own Barrachander Quarry at Taynuilt, Argyll.
Until three years ago they operated a Volvo G930 motor grader, with the traditional complex 10-lever hydraulic/
COPE WITH ANYTHING
THAT WE COULD THROW mechanical control system. When it came
AT IT IN SCOTLAND” F due for replacement and since Volvo had pulled out of this sector of the market, it was time to consider a different brand. Calum therefore spent three days at the Bauma 2019 show, on a mission to fi nd the most appropriate grader to suit their requirements. He said, “I visited Bauma to look at every single grader that was available, such as machines from Cat, Hidromek, Case and a few models from Chinese manufacturers. I then got into a detailed conversation with John Deere’s product marketing manager, Luke Kurth. I spent over an hour with Luke, going from front to back of the new 672GP, and was impressed with its
Left and below: We met man and machine while they were undertaking some light annual maintenance work on the Troustan Forest road line in Cowal, Argyll.
build quality, ground clearance and other key specifi cations. When I sat in the machine, the difference in cab comfort, controls and ease of operation really stood out for me.”
Calum was invited to put the Deere motor grader through its paces at the Windhagen factory of the Wirtgen Group in Germany, which John Deere had acquired 2017. During the Bauma 2019 show they announced the availability of their 672GP and 622GP graders, initially in Germany and France, through Wirtgen Group subsidiaries.
Calum continued, “During the live demo, the claims made at Bauma were brought to life, as the 672GP has more engine torque, power and more pulling performance on the mouldboard. For me, this was the number one feature, as we wanted a highly productive grader to cope with anything that we could throw at it in Scotland. This, along with the very quiet, comfortable cab’s great visibility, plus ease of servicing and good dealer back-up made for a complete machine package. John Deere products are not new to us, as we have run a number of their agricultural tractors in the past.”
NEW GRADER FOR UK
A few weeks after the Bauma show, Calum and his team were due to start on a subcontracted job to rebuild a haul route to ease the way for contractors upgrading a long stretch of electricity pylons. Believing the six-wheel drive John Deere 672GP motor grader was the best option for their work on forestry and renewable energy access roads, Calum quickly made a deal for the high-spec Bauma show machine. It is a GradePro (GP) variant, which includes dual multifunction joystick
controls, a far cry from the control layout of their older generation Volvo. The new machine’s ‘Automation Suite’ reduces the number of controls needed to perform common tasks, such as auto-articulation and blade fl ip, and includes operatorselectable pre-sets. In addition to a conventional steering wheel, the 672GP also features joystick steering, together with automatic return-to-straight. The Deere motor grader is of an open“GRADEPRO IS ALSO architecture design, which allows the use EXTREMELY USEFUL NEAR of any brand of grade-control systems in the future, however all GP models come with THE END OF A LONG SHIFT, automated cross-slope function. This makes
Left, above and below: One of the key selling points of this generation of John Deere motor graders is its cab, which off ers great visibility and features easy-to-use multi-function joysticks, a far cry from the traditional 10-lever set-up.
SPECTACULAR SITE VISIT
We met Calum and his grader in the forests of Argyll, overlooking the stunning scenery at the head of Loch Striven. Together with a Valtra tractor pulling a vibrating roll drum, he was resetting the cambers and giving a light dressing to the decent-looking surface of a forestry road. An access route, constructed by A&L McCrae early last year, that many thought was an impossible dream.
Also on site was Stuart Hansom, general manager of Euroforest, one of McCrae’s valued customers, who explained the background to this 2.5km road line. The Troustan Forest in Cowal was an isolated block of mature commercial trees, but with no formal access in place. The requirement was to provide unrestricted HGV access to allow the timber to be harvested and transported. Local forestry contractors had been contemplating such a road line for the last decade; some reckoned it just couldn’t be done, due to the terrain and extreme ground conditions. More recently, Gresham House, representing the current owner of Troustan Forest, approached forestry consultant Euroforest to cost the various access options. During these discussions, it became clear that Alistair McCrae not only thought that the road could be built, but his team had the expertise and machinery to undertake the job to the highest possible standard. Accessing through a neighbouring property, the fi nal design involved building 2.5km of forest road across extremely challenging terrain. Once the route of the new road line was marked, the trees were felled by Dick Brothers, before construction works could begin. Led by Alistair, the McCrae team deployed to site in January 2021 with three excavators: a Liebherr R926, a Doosan DX225 and a DX300 equipped with a Rammer 3099 breaker, supported by 30t-capacity Volvo articulated dump trucks. Once the formation was in place, they mobilised their Powerscreen PT400X crusher to produce the required surfacing stone, which was profi led by the John Deere grader and rolled in situ. Works were completed in April 2021. Due to environmental constraints placed on this isolated site, timber harvesting and haulage at Troustan is restricted to the winter months, as client Stuart explained, “As a consequence, we expect to see a level of degradation in forest roads that are worked so intensively over the winter months, when rainfall levels are at their highest. I’m pleased to report this road has recently withstood 21,000 tons of timber movement by Peter McKerral and showed far less wear and tear than was anticipated. It’s a testament to the contractors that built it.
“Nevertheless, ongoing road maintenance is recognised as being a key component in the management of any large-scale commercial forest. And given the superb performance of the Troustan road to date, it was an easy decision to ask Alistair’s son Calum to return to give the road a light grade and roll, in preparation for the next round of felling works.”
JOHN DEERE 672GP WALK-ROUND
The 672GP is powered by a six-cylinder, nine-litre, Stage 5 ultra-low emissions John Deere engine, producing up to 250hp in 7th gear. The main direct-drive transmission is John Deere’s PowerShift Plus box, providing modulated shift-on-the-go and event-based shifting (EBS). The eight-speed box covers speeds from 4.0kph to 45.5kph.
It also has two independent front-wheel drive motors and hydraulic pumps, so that each front wheel station can be sent exactly the right amount of power and fl ow to maintain traction, virtually eliminating the possibility of wheel-spin. This results in automatic traction control and the power bias across the six-wheel drive being adjustable on the fl y, to suit the steepness of the grade and ground conditions.
The motor grader’s automatic, dual-path hydrostatic drive is said to increase tractive eff ort and front-end control. This includes separate left and right systems, with variable-displacement pumps, axial-piston wheel motors and freewheel at transport speeds. It also includes a 15-position rotary ‘aggressiveness’ control and inching capability, together with a precision mode when the machine is propelled by its front wheels only.
The mouldboard is made from high-strength, pre-stressed, wear-resistant, high-carbon steel and features reversible end bits; its base length is 3.66m, it is 610mm high and 22mm thick. The mouldboard’s side-shift wear system includes quick-change replaceable wear inserts and a quick-adjust jackscrew system. Calum prefers to use original Deere cutting edges, as they are far more durable than other wear parts he has tried.
The mouldboard is attached to a heavy-duty excavator-style slew ring known as a circle. Calum’s machine has the standard unit, however later machines could be specifi ed with the premium circle, which is a fully-sealed, maintenance-free bearing and pinion design that runs smoother and quieter, ideal for use with a grade-control system.
it simpler to hold a consistent slope, by allowing operators to run a single control, while the machine’s black boxes adjust the opposite side of the blade.
This 2019 motor grader represented the fi rst item of John Deere construction machinery to be sold in the UK for around 50 years. This landmark deal kick-started the introduction of these graders into the UK market, as seen at the recent Hillhead show.
Last year, John Deere made a major investment in the Scottish market, with a new £2.5m customer service centre located in Perth. Believed to be unique in JD’s global dealer network, it supports both Deere’s forestry machines and the full range of Wirtgen Group road construction kit. The 1300sq.m building includes a four-bay repair shop and a parts warehouse. It acts as a hub for Wirtgen’s home-based sales and technical staff and complements John Deere’s UK forestry base at Carlisle. Calum reports that he has a great working relationship with Wirtgen UK, so much so, that he helps to train new operators of Deere graders.
As for his own machine, now with over 1100 hours on its clock, Calum stated, “This Deere grader’s reliability has proved to be outstanding over the last 2.5 years. It has the highest uptime of any machine in our fl eet, and it’s never missed a beat since the day we bought it from the Bauma stand back in 2019.”
Above and above rright: The 672GP motor grader is powered by a nine-litre, 250hp John Deere engine, driving the main PowerShift Plus eight-speed auto box, together with independent front right and left hydrostatic drives. OPERATOR FEEDBACK
Watching an experienced and skilled motor grader operator at work is always a joy. In the stunning landscape of the head of Loch Striven (see panel), Calum provided a master class by completing quick and accurate passes, using the mouldboard at different angles of attack to move the stone around. He said, “I tend to do a lot of grading work just using my eye in the fi rst three or four passes. However, on the fi nal pass, or where work has to be carried out to a very high spec, or where we are instructed to carry out a crossfall of say 5%, you just set the GradePro to this requirement.
“The system works simply and easily off the right-hand control, which cuts down three or four combinations of control inputs in order to hold the mouldboard absolutely bang on to 5%. GradePro is also extremely useful near the end of a long shift, as it dramatically lightens the operator’s workload and saves constantly looking down at the mouldboard.”
Before joining, and now running the family fi rm, Calum did his apprenticeship
with Caterpillar distributor Finning, so chooses to do all the regular servicing of the grader in-house, under a service parts contract with Wirtgen. He fi nds the 672GP a very easy machine to work on, as it has fast drain connections using a vacuum pump and fi ll valves all located at ground level, as are all the fi lters. He particularly likes the ease with which the mouldboard wear shims can be adjusted to take up any slack, with a few quick turns of a spanner on a simple adjusting bolt and locknut design.
The 250hp, six-wheel drive powertrain provides excellent levels of traction and rim-pull and overall Calum thinks the 672GP is an extremely wellengineered machine. It includes everything from good work and access panel lights, to the diesel and AdBlue caps behind sealed doors to stop dirt and water ingress. This ex-show machine also has the optional winter pack, with extra fi lters and bigger mudguards. This example has also been fully kitted out to meet UK quarry regulations, with rear and side hi-vis chevrons, blue strobe lights, a reversing alarm and the
like. It has occasionally been deployed to the Glensanda super quarry, to help maintain the haul roads when the site’s own motor grader is in the workshop.
Left and right: All the routine service points fall easily to hand from ground level; note the dust- and rain-protected diesel and AdBlue refi ll points.
This John Deere grader, the fi rst example in the UK, has performed faultlessly since its arrival in Scotland shortly after the 2019 Bauma show.
CONCLUSION
This John Deere 672GP is registered for road use and, although the standard front and rear cameras are great while working, something more was required when on a public highway. Specifi cally, when nosing out of narrow road junctions that offer limited side visibility, as nearly fi ve metres of machine extend out before the cab reaches the head of the junction. To dramatically improve visibility in these situations, two side-facing high-tech cameras have been retro-fi tted to the ends of the light poles on the front of the machine.
Calum said, “Our local electrician, Jason, did a fantastic job of wiring the two extra cameras into the existing screens. I can now sit in the cab confi dently seeing left and right of a junction before starting the manoeuvre. And since it also has night vision capability, along with the very powerful LED work lights, it will be essential during the darker winter months.”
Calum is clearly delighted with the performance of the John Deere 672GP, which provides that much sought-after combination of high power and low fuel/ AdBlue burn. The contents of the 416-litre diesel tank last 2.5 shifts. Calculated on such forestry road jobs on a ‘metres-perlitre’ basis, Calum reckons he enjoys at least a 25% productivity gain over his previous grader.
As Alistair and Linda McCrae ease themselves into retirement, Calum concluded, “I’d like to pay tribute to my mother and father for their hard work, setting high standards and professionalism over the last 50 years. As I take on the running of the business, I hope to follow their lead and wish them a long and happy retirement.”
