OMEF BF cutter bars

Forty kilograms is the number to start with. The BF1200 weighs 40 kg, the BF1500 43 kg and the BF1700 46 kg, and all three shear 30 mm material across 1.2, 1.5 or 1.7 m of working width on carriers from 1 to 5 tonnes at 20 to 40 L/min. An excavator attachment that two people can lift onto a stand is unusual enough that it changes how the tool is bought, used and priced, and this page is mostly about the consequences of that weight.

Model	Weight	Working width	Carrier	Max material	Flow
BF1200	40 kg	1.2 m	1–5 t	30 mm	20–40 L/min
BF1500	43 kg	1.5 m	1–5 t	30 mm	20–40 L/min
BF1700	46 kg	1.7 m	1–5 t	30 mm	20–40 L/min

What 40 kg buys on a mini excavator

The obvious benefit is that the lift chart stops being part of the conversation. A 1.5 tonne machine can hold a BF at full reach and full height all day without the operator watching the tipping edge, which on a small carrier is otherwise a constant background calculation. The lift chart guide explains why that is normally such a constraint on machines of this size.

The less obvious benefits matter more over a season. A light bar can be held against a hedge face for long stretches without the boom being feathered to keep the machine settled, so the operator works at a steady pace rather than in a sequence of set-ups. It can be angled up over a fence line or down a table drain without the carrier needing to be repositioned to stay stable. It can be swapped in the field by two people in minutes, so a machine can do an hour of trenching and an hour of hedging in the same visit. And it travels with the carrier on an ordinary plant trailer, which is what makes a scattered rural or council round economic at all; the transport and mobilisation guide covers where mobilisation starts to dominate a small job.

There is one place the weight works against the buyer. At the bottom of the carrier band, the constraint is not mass but leverage: a 1.7 m bar hanging off the dipper of a 1 tonne machine puts its centre of gravity well outboard, particularly when the bar is angled. On a 1 tonne carrier the BF1200 is the sensible bar and the BF1700 belongs on 3 tonnes and up, even though the difference between them is 6 kg.

Pricing linear work properly

Everything about this family is sold by the metre, so this is the page in the range that works the production arithmetic through in full. The same structure applies to any continuous pruning tool; only the inputs change.

Take an illustrative case and label every assumption. Assume a 1.5 m high hedge face that a 1.7 m bar finishes in a single pass, an average working speed that yields 400 m of finished face in a productive hour, and a six-hour productive day inside an eight-hour shift. That is 2.4 km of face a day. Now put the real costs against it. Assume the traffic control crew, the truck and the operator are committed for the shift whether the bar is 1.2 or 1.7 m wide. If a narrower bar needs a second pass on the same face, the daily output halves to 1.2 km while the cost of the day barely moves, and the cost per finished kilometre doubles.

That is the whole commercial argument for width on linear work, and it explains why the widest bar the site and carrier allow is usually the right purchase. It also explains why measuring passes matters more than measuring speed. A tall hedge face needing two passes with any bar is a different job from a 1.5 m face finished in one, and no amount of forward speed recovers a pass that should not have been needed.

Three adjustments make the model honest. First, subtract the non-cutting time inside the productive hour: repositioning the machine, moving cones or a truck, waiting on traffic, and clearing a driveway. On a rural verge that can be 10 per cent of the hour; on a built-up street it can be a third. Second, count cleanup separately, because 30 mm cuttings on a sealed shoulder must be swept or collected before a lane reopens, and that work is often the reason a job runs past the closure window. Third, use your own numbers: forward speed on Australian native regrowth is not the same as on a European farm hedge, and the only figures worth tendering on are the ones measured on a representative section of the actual corridor. The tender rate guide and the cost per unit calculator turn those measurements into a rate.

Where the bar stops: green, sound, 30 mm

The BF cuts with a knife section moving across a fixed comb, the same principle as an agricultural mower bar. That gives a clean shear on green material up to 30 mm and very little else. Dry dead wood does not shear; it shatters knife sections, and a verge left for several seasons will be full of it. Multi-stemmed native regrowth that has gone woody at the base is the same problem, and a fence wire or a piece of star picket buried in a hedge line will stop the day outright.

The practical rule is that the BF is a maintenance tool for growth that is cut regularly. Where a corridor has been allowed to run, the reclamation pass belongs to the TRI bar at 100 mm or the BTD disc heads at around 150 mm, and the BF takes over afterwards. Finer material than the BF’s class, formal hedges and young soft growth, is TG territory where finish is what the client is paying for. Individual limbs above 100 mm are CS work, and anything that must be lowered instead of dropped is grapple saw work, which the pruner versus grapple saw comparison sets out. The mechanical pruning guide covers the whole ladder.

Width, incidentally, has nothing to do with capacity. All three BF models cut the same 30 mm class; the extra 500 mm between the narrowest and widest is coverage per pass and nothing else. The TRI page works that point through in detail, because it is the family where buyers most often misread it.

Circuit, bracket and consumables

The published flow window of 20 to 40 L/min covers most mini excavator auxiliary circuits, which is one reason the BF is easy to put to work. Pressure, circuit type and any drain requirement are not published in our model data, so ask Machinery Specialist for the current sheet and confirm whether the bar runs on a single-acting line with a free return or a double-acting circuit. The return path is the part to be careful about: a continuously running motor should return to tank rather than through the control valve, and the hydraulic matching guide explains why. The 1 to 5 tonne class page covers the carriers this bar is built around.

Specify the angle adjustment deliberately. Fixed, mechanical or hydraulic tilt determines whether the bar can follow a batter, a vertical face and a table drain in one run or whether the operator is fighting boom geometry all day. Settle hose lengths for the actual dipper, the flow setting to be programmed on the carrier, and the delivered weight in the configuration ordered.

Knife sections, comb fingers, hold-down clips and the drive are the consumables. They are inexpensive next to disc or pruning blades, and they are also what stops a contract when a stone or a wire goes through the bar, so the useful question at quotation is not what they cost each but whether a kit is on the truck before the first stoppage. Price a knife and finger kit with Machinery Specialist, confirm Australian stock, and use the approach in the wear parts guide. Exclusion zones, applicable WHS procedures and manufacturer instructions apply even on light material, because a bar throws cuttings and fence wire further than most operators expect.

Who ends up owning one

Three buyer types keep appearing for this bar, and their reasons differ enough to be worth naming.

Farm businesses buy it as a second use for an excavator that was bought for something else. The machine already exists, the bar costs a fraction of it, and shelterbelt faces, orchard row edges and fence lines that used to be done with a tractor slasher or by hand become a job someone can do in an afternoon. The economics are about utilisation of a machine already on the books rather than about metres per hour.

Councils and their contractors buy it for the scattered round: a list of sites across a shire, none of them big, all of them needing a tidy edge. Here the deciding factor is that the whole rig travels on a trailer, so the day is spent cutting rather than floating, and the crew is one person.

Small contractors buy it as the tool that gets them onto maintenance work without a corridor-sized machine. That is a sound plan with one condition: the contract has to be genuine maintenance. Bidding a neglected verge with a 30 mm bar is how a profitable job becomes an unprofitable one halfway through the first kilometre.

In all three cases the same question decides whether the purchase works, and it is not about the attachment. It is whether the vegetation on the round has been kept inside the class the bar was built for, because the bar cannot put a corridor back; it can only keep one where it already is.

Confirm before ordering

• Material is green 30 mm class growth on a maintenance cycle, with any backlog priced as a separate reclamation pass
• Passes per metre of face measured on a representative section, not assumed
• Width chosen on pass count and access, since all three models cut the same class
• Stability at full reach checked with the widest bar on the smallest carrier in the fleet
• Auxiliary flow inside 20 to 40 L/min, with pressure, circuit type and drain confirmed in writing
• Return routed to tank for continuous running
• Angle adjustment type and hose lengths specified for the actual dipper
• Knife section and comb finger kit priced, in Australian stock and carried on the truck
• Non-cutting time and cleanup carried in the metre rate

Frequently asked questions