Powerhand EX25 grapple saw

The lightest saw head Powerhand builds for an excavator

Powerhand’s rigid forestry excavator grapple saw range runs EX25, EX28 and EX36. The EX25 is the only one built around an 8 to 12 tonne carrier and, at 651 kg, the lightest saw head the company offers for an excavator. That is the commercial argument in one line: a council crew or an arborist running a 10 tonne machine gets a head that grips a standing stem, cuts it and keeps hold of the severed piece, without handing most of the boom’s capacity to the attachment. The grapple saw buying guide explains the three mounting architectures Powerhand builds.

Where the work is handling rather than cutting, the matching EX25 forestry grapple carries the same 0.25 m² capacity and 1,641 mm opening at 400 kg with rotator. The 251 kg between them is the price of the saw, and on a carrier this size it is a price worth counting rather than assuming.

Opening, bar and cut: three numbers that are not interchangeable

The 1,641 mm maximum opening is how wide a stem or limb passes between the tine tips, and it matters more on a saw head than on a plain grapple because the jaws must close around standing timber before the chain touches it. It reaches around trunks considerably larger than the saw will sever, which is the right way round.

The 900 mm bar and the 600 mm maximum cut are separate figures too. Bar length is what the saw box carries; the cut is what the head will pass through in one plunge with the timber gripped. Treat 600 mm as a mechanical ceiling rather than a production target, because chain load and cut time in dense hardwood rise steeply as you approach it. The 0.25 m² capacity, meanwhile, describes bundled material, which is what the head holds when it is used for gathering rather than cutting.

The 651 kg attachment weight is the number that belongs in every lift calculation. Confirm in writing whether it already includes the Indexator saw rotator and the coupler in the configuration you are being quoted.

Saw capacity is not safe piece capacity

This is the distinction that causes the most trouble on small carriers, so it is worked through in full here and referred to from the rest of the range. A 600 mm rating tells you what the chain will pass through. It tells you nothing about what the machine can hold afterwards, because the moment the cut finishes the carrier is suspending head, rotator, coupler and a severed section of timber at whatever radius the boom happens to be at.

Work it through illustratively. Assume a 10 tonne excavator whose chart shows 1,500 kg at the radius the operator is actually working at, and an assumed 150 kg coupler. Deduct those and the 651 kg head and about 700 kg is left for the piece.

Now convert that into a length. A 600 mm diameter section has a cross-sectional area of about 0.28 square metres, so assuming green eucalypt near 1,100 kg per cubic metre it carries roughly 310 kg per metre of length. Seven hundred kilograms therefore buys a little over 2 m of it, not the 5 m that the same head might manage in softwood. Take it further: the same sum at the maximum cut but on a 400 mm stem, which is about 138 kg per metre on the same assumptions, allows a piece around 5 m. That is the practical shape of the constraint. Diameter drives the per-metre mass as the square, so halving the diameter roughly quarters the weight, and the operator gains far more usable length by cutting smaller sections than by working to the rating.

Everything in that arithmetic except the 651 kg is an assumption, including the chart figure, the coupler mass and the timber density. Put your own machine through the lift capacity calculator and read the lift chart and attachment mass guide before planning any cut, and add margin for the dynamic loading a swing or a slope introduces.

What the EX25 is bought for

It earns its keep where an 8 to 12 tonne machine already suits the site: council parks and urban vegetation, road corridor clearing where every closure carries traffic control cost, storm damage and dangerous trees where a hung-up limb must be gripped before it is cut, and powerline and transmission easements. What it delivers is control of the severed section rather than cuts per hour, and the case for it rests on nobody standing under the load.

Plan each piece deliberately: length, diameter, density, centre of gravity and the path it will take to the ground. Where the material goes into a chipper, size the sections to the infeed so the saw is not cross-cutting the same piece twice. Australian hardwood density shortens safe sections noticeably against pine.

Stepping up, or stepping sideways

On a 12 tonne machine regularly meeting 500 mm and larger hardwood, cut times lengthen, the 0.404 inch chain is working hard and the boom has little margin left for the piece. That is the point to look at the EX28, which keeps the 600 mm cut but adds saw motor and chain pitch choices across a 12 to 25 tonne band. There is no smaller rigid saw. Below 8 tonnes a tree shear is the realistic path, and the tree shear vs grapple saw comparison shows where its simpler and faster cycle wins.

Settling the configuration

The figures here describe the rigid excavator build. Powerhand also offers the EX25 head on a tiltrotator and in a tree-care worm-drive configuration, each with its own weight, hydraulic demand and price, so state the architecture in writing before comparing quotations or the comparison is meaningless. Within the rigid build, confirm the Indexator saw rotator with continuous rotation, a saw motor displacement chosen against the carrier’s measured auxiliary flow rather than the largest motor on the list, 0.404 inch chain, automatic tensioning and the chain lubrication reservoir. The hydraulic matching guide explains why an under-flowed motor cuts slowly and runs hot while an over-sped one wears early.

On consumables, budget the saw side first, tracking chains per day and bars per month so the tender rate reflects what the head costs to run; the EX28 page covers how chain pitch changes those items. Machinery Specialist is the Australian distributor and the wear parts guide gives a pricing checklist.

Confirm before ordering

• Architecture written on the quotation: rigid excavator grapple saw, not tiltrotator or tree-care
• Delivered weight, stating whether the Indexator rotator, coupler and hoses are inside the 651 kg
• Chart figure at your real working radius, with that weight deducted before any piece is planned
• A worked piece length for the largest diameter you expect to cut, on your own density figures
• Saw motor displacement selected against measured auxiliary flow and pressure
• 0.404 inch chain, bar, automatic tension and lubrication reservoir specified
• Chain, bar, sprocket and seal pricing with Australian stock location
• Transport stand that protects the bar and hoses on the float

Frequently asked questions