Profile: Custom-built shelterbelt trimmer

By: Emma Brown, Photography by: Bruce Taylor

When Bostock Shelter Trimmers' Rob Bostock was looking for another shelterbelt trimmer, he opted for a custom-built one

Given that shelterbelt trimming is the type of business that commonly sees the owner-operator behind the wheel, Rob Bostock, who has been in the industry since 2012, wanted his machine to be built once and built exactly to his specifications.


Loyal to his original brand, Rob reckons there’s only one type of tractor on the market suitable for his business.

"And sorry folks, that is a John Deere," he says. Given Rob’s passion and knowledge for machinery, he set about undertaking some serious research for the fabrication of his machine. With a clear vision in his head, he knew what his requirements were, so set to in finding the right tractor for the job.

The Bostock family

Rob eventually found the John Deere 6620 IVT he wanted, with low hours, so had it transported up from Canterbury. Buying new with a narrow cab wasn’t an option, as for his specialised requirements, all of the body panels and most of the cab needed to be removed.
With his proposed transformation pretty comprehensive, Rob wanted to find a one-stop shop to turn his ideas into reality.

Browne Engineering in Tauranga came highly recommended, with Andrew Browne and his team well known as multi-talented engineers. Rob had previous experience with the Browne team so had no hesitation in handing his precious project over.

The roof was altered to fit a large grass screen and ducted leaf blower

The first task was to remove all of the John Deere’s body panels and strip out the cab. The roof was altered to incorporate a large glass screen, sloping to the front to enable a ducted compressed air hydraulic leaf blower to blow debris off the cab. This altered roofline also increases the upward vision needed in shelterbelt trimming.

The only aspects of the cab that haven’t been altered or replaced are the basic structure and the rear window. The doors now have flush fit handles and heavy-duty steel hinges. The screen and side glass is 20mm "near bullet-proof" mounted in robust frames.  

The bonnet was raised, extended, and strengthened

Inside the cab is a reverse camera with the screen permanently on. The rear guards are integral with the cab, and like the raised and extended bonnet, are fabricated from 6mm plate. The bonnet is opened by using hydraulic rams activated by the tractor’s hydraulics.

All of the hydraulic work has been carried out by Browne Engineering, with even the engine hydraulic hoses done in-house. The pumps, control valve, and motor were supplied by Windust Hydraulic Services in Hamilton.

The bonnet includes a secondary screen for dust collection, additional protection for the radiator

Inside the front of the bonnet is a secondary screen for dust collection. This protects the radiator while a belly pan protects the underside of the tractor. On the right-hand side, a storage/toolbox is built into the step, which also includes a pie warmer for help getting through long days.

Detachable headlights are stored in this compartment along with the fire extinguisher. Inside the toolbox is a little shelf that Rob calls his pie warmer. The exhaust system exits in front of the toolbox.  

Storage and a toolbox are built into the step along with a pie warmer for Rob

On the left-hand side sits the 280-litre fuel tank. The built-in steps take the same shape as the toolbox on the other side, as Rob wanted the lines of the tractor to look the same on both sides. The fuel tank also has a large inspection cover.

The rear wheels sit on new rims that have been widened and fitted with 23, 1-26 Skidder tyres.  The front rims are TRS with 15.5/80–24 BKT implement tyres. Tyre inflation lugs are fitted to the inside of the rims.

The finished custom build meets the exacting standards of Rob Bostock

The Palfinger boom was reconditioned and modified by Browne, and the team there also custom-built the lift ram and brass adjusters on the slides to keep it square when it’s extended out. The Palfinger is mounted on the oil tank, which centre pivots on chassis rails.

These also act as air tanks for the compressor. All hydraulics are fully enclosed but accessible for maintenance.  

The machine is a left-hand side cut. The Palfinger reaches up to 15 metres and flat tops at 12.5 metres. Steve Pickering from Welcome Bay, who has also done some of Rob’s maintenance work over the past years, fabricated the cutting head on the machine, using 855mm blades with a 4mm gap between each blade.

With such a precise custom-build required, Rob is delighted with the finished product, which took many hands and skillsets to complete. The finished build is already hard at work with the rest of the Bostock Shelter Trimmers fleet.

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