A commercial harvesting head should be considered a machine in its own right. It contains a considerable percentage of the technology responsible for actual production: gripping, felling, feeding, delimbing, diameter measurement, length measurement, bucking, top sawing, colour marking, multi-tree handling and debarking.
The most common and most expensive specification error in Australian forestry is confusing three different numbers: the optimum DBH range, the recommended maximum regular DBH, and the absolute maximum cutting capacity. Manufacturers publish all three. Buyers routinely quote only the third.
The head is where most of a cut-to-length system's technology, most of its production and most of its downtime live. Treating it as an accessory to the carrier is the most expensive habit in this market.
Australia buys heads for two quite different jobs. One is the purpose-built CTL carrier, where head and machine are matched by the manufacturer. The other — far more common among medium contractors — is the excavator conversion, where a 20-30 tonne machine already in the fleet becomes a landing processor. The second route carries lower capital and broader resale, and it is why excavator-class heads are so well represented here.
Eucalyptus is the local complication. Roller configuration, debarking capability, feed force and structural durability all differ from softwood requirements, and manufacturers publish eucalyptus configurations precisely because the standard build does not transfer.
Indicative published manufacturer and distributor figures. Confirm every specification, lift chart and hydraulic requirement with the manufacturer or authorised dealer before purchase.
The heavy processor-head category, positioned for demanding hardwood and softwood harvesting and processing.
| Head weight | 3,560 kg |
|---|---|
| Recommended carrier | 27 t and above |
| Maximum butt-saw capacity | 815 mm |
| Maximum delimbing opening | 710 mm |
| Maximum feed-roller opening | 875 mm |
| Feed speed | up to 5.2 m/s |
| Pump requirement | 320-360 L/min |
| Hydraulic pressure | up to 35 MPa |
The clearest published illustration of why optimum diameter, not maximum diameter, is the number that matters.
| Weight | ~1,480 kg |
|---|---|
| Minimum pump capacity | 200 L/min |
| Recommended working pressure | 26-30 MPa |
| Feed roller opening | 630 mm |
| Feed force | ~38 kN |
| Standard cutting diameter | 700 mm |
| Optional cutting system | up to ~810 mm |
| Feed speed | up to ~7 m/s |
| Highest-productivity DBH range | ~160-510 mm |
The heavier end of the SP range, positioned for heavy softwood, crooked hardwood and demanding processing.
| Standard published weight | ~1,792 kg |
|---|---|
| Minimum pump capacity | 250 L/min |
| Feed force | 45 kN |
| Cutting capacity | 800 mm |
| Feed opening | ~700 mm |
| Recommended optimum DBH | ~250-500 mm depending on configuration |
An excavator-class harvesting head for roughly 21-25 tonne carriers, with eucalyptus roller configurations available.
| Weight | ~1,342 kg |
|---|---|
| Maximum cut | ~710 mm |
| Maximum feed force | 31.3 kN |
| Maximum feed speed | 5 m/s |
| Flow | 200-330 L/min |
| Excavator class | ~21-25 t |
The heavier Log Max head for roughly 25-30 tonne carriers, again with eucalyptus roller options.
| Weight | ~1,897 kg |
|---|---|
| Maximum cut | ~800 mm |
| Maximum feed force | 45 kN |
| Maximum feed speed | 5.2 m/s |
| Flow | 250-350 L/min |
| Excavator class | ~25-30 t |
The bar is what the head can cut. The darker band is where the manufacturer says it is most productive. Where no band is shown, no optimum range is published — ask for it.
Full published specifications, commercial fit, and what to verify before signing — for each machine.
Heavy processor head for demanding hardwood and softwood, 815 mm butt-saw capacity on a 27 t+ carrier.
The clearest published case for optimum over maximum: 700 mm cutting capacity, 160-510 mm best production.
Heavier SP head for heavy softwood, crooked hardwood and demanding processing — 800 mm capacity, 250-500 mm optimum.
Excavator-class harvesting head for ~21-25 t carriers, with eucalyptus roller configurations available.
The heavier Log Max head for ~25-30 t carriers — more capacity and feed force, at 555 kg more mass.
These are the numbers that determine whether the purchase works. Specification sheets rarely contain any of them.
Assemble every one of these before contacting a supplier. Any line you cannot answer is where your commercial risk sits.
Each of these is a documented pattern, not a hypothetical.
Obtain consumable prices at quotation stage and model annual expenditure. Use the dealer quote checklist.
Hours alone are not enough. Work through this in order.
Purchase price is the smallest part of most forestry equipment decisions. These are the variables that decide what the machine costs per unit of saleable production.
Head economics are driven by consumables and by matching, not by purchase price. A head that is one class too large costs you boom payload, agility and transport weight on every cycle for its whole life, in exchange for capacity used occasionally.
The specification error that costs most money is diameter. Manufacturers publish three separate numbers — optimum production range, recommended maximum regular DBH, and absolute maximum cutting capacity — and buyers routinely quote only the third.
Model these against your own contracted hours rather than accepting a generic hourly rate — the machine cost calculator works the arithmetic with your figures, and the bottleneck analyser shows whether the machine is the constraint at all.
The same machine class suits very different businesses in very different configurations. These are the situations that recur.
Specification sheets are written for global markets. These are the factors that change the answer here.
None of these are proof of a bad supplier. All of them are reasons to keep asking.
Any line you cannot answer is where your commercial risk sits. Take this to the supplier meeting.
The comparisons, buyer profiles and fleet packages that turn on this machine.
The cut-to-length machine — fell, delimb, measure, buck and sort in one cycle.
Excavator or purpose-built machine — the biggest single commercial buying decision.
Carries cut-to-length logs completely off the ground — payload × trips per hour is the whole economic model.