It looks like Timberwolf's famous TW150, often seen towed on motorways and around towns, but this chipper is a step up.
For starters, it is faster than the 150. It is also stronger and much easier to service. Yet despite the improvements, the 230 remains a sub-750kg chipper that can be towed without the need for an additional trailer licence.
The weight is crucial for many. Practical arboriculture, by its nature, is a younger person's business. But chippers still need to be towed. The cut-off point for legal towing without extra tests is 750kg. This one weighs just 749kg, and that is with a full fuel tank and all the fluids.
A larger and more powerful chipping rotor lies at the heart of the new machine, ensuring that everything we throw at it is neatly chipped and thoroughly dispersed. Although Ford describes the GreenMech as having "a slightly more fluid intake", we find the TW230 takes, handles and processes the timber well.
"There is no side swipe of the timber as it is fed in but there is a bit of bounce," says Ford. He appreciates the open-top funnel, large chipper throat and wide rollers. Throughput is fast and the ejection of chips is remarkable. "This really fires the chips out," he adds. "We have thrown them well into the wood and out of the way." The chips are uniform, with potential for use as woodchips.
With a wider axle and a deeper chassis beam, the TW230 is stable on the ground. Access to the rotor, anvil and blades is simple, but what Ford really likes is the remote greasing. "It's great that you don't have to go into the machine for daily maintenance - that's a definite advantage," he points out. "You don't want to spend minutes out of your day hunting for the grease nipples."
During the test, the bottom bar tripped once but the machine was up and running again quickly. Porter finds the machine easy to control, including forward/reverse movement of the rollers, and he is impressed with the crushing power of the rollers. But more important for him is the weight of the machine. "I don't have a trailer licence yet so I would be looking for a sub-750kg machine," he explains.
Timberwolf has paid a lot of attention to detail - witness the auto-latch cast tow head and LED light board. We reckon that tree surgeons, contractors, local authorities and hire shops will appreciate both the machine and the price. Ford says: "The price is a big advantage, especially for anyone just starting up a business."
Capacity 160mm diameter (6.3in)
Engine 35hp four-cylinder, water-cooled Kubota diesel
Drive Direct, three belts
Feed roller Twin horizontal hydraulic
Blades 135x100mm, double sided, fully hardened
Rotor speed 1,920rpm
Power control Auto feed control
Discharge chute rotation 270 degs
Fuel capacity 18 litres
Transport length 3.3m
Weight 749kg including full tank of fuel and other fluids
List price £16,995 + VAT
Tel Timberwolf - 01449 765800
Tested This Issue
GreenMech Arborist 190
GreenMech ArbTrak 190
The Review Panel
Matthew Ford, arboricuture trainer and assessor, Broomfield Hall Campus, Derby College
Douglas Porter, former Derby College student
As a professional arborist you want to get the job done quickly and cleanly. So why spend time loading branches onto a lorry, lashing them down and making three or four trips back to the depot when you can chip the timber and reduce the volume for single-trip transportation or, better still, leave the chippings on site, blown back into woodland? The woodchipper has become indispensable for anyone involved in tree maintenance.
In this test we take three of the latest models - the Timberwolf TW239DHB sub-750kg and the GreenMech Arborist 190 as a road tow model and also self-propelled on tracks - to the Broomfield Hall Campus of Derby College.
There we ask Matthew Ford to put the machines through their paces. Before coming to the college as arboriculture trainer and assessor, Ford worked in the industry, where he used Jenson woodchippers. Having no previous experience of either GreenMech or Timberwolf, he is well placed to review the new models. We were also joined for part of the test by Douglas Porter, who having studied at Derby is now a tree surgeon.
The weather on the test days was dry and sunny. Willow timber was used through all three machines.