What is a cone splitter?
A cone splitter is a log splitter that is mounted on an excavator or mini excavator as an attachment. A hydraulic motor turns a threaded splitting cone. The thread pulls the cone into the wood and the increasing diameter forces the log apart. The German term is “Kegelspalter”.
BLACK SPLITTER in Willingen, Germany, manufactures cone splitters for carrier machines from 0.8 to 40 tonnes. This page explains briefly how a cone splitter works, what it consists of and which designs are available.

How a cone splitter works
- Powered by the excavator hydraulics: the cone splitter is connected to an auxiliary hydraulic circuit of the excavator, which supplies the hydraulic motor with oil.
- The cone rotates: the motor – on larger models via a planetary gearbox – turns the splitting cone.
- The thread pulls into the wood: the tip of the cone is threaded and draws the cone into the log.
- The log splits: the deeper the cone goes, the larger its diameter. The wood is forced apart.
The excavator moves the attachment to the wood. Heavy logs do not have to be carried to a splitter by hand.
Design: the parts of a cone splitter
- Hydraulic motor: produces the rotation. Some models are available with a choice of motors.
- Planetary gearbox (depending on model): increases torque. The SB, SBX and SBXX reach 12,000 to 60,000 Nm.
- Splitting cone: threaded cone with a diameter of 200 to 400 mm, depending on the model.
- Mount: connects the attachment to the quick coupler or dipper arm of the excavator. Suitable mounts and adapters are available for different systems.
- Grab (depending on model): holds and moves the wood, for example on the SG1 and SG3.
Designs and models at a glance
The figures are taken from the technical data on the product pages (without excavator mount, back plate and hydraulic hoses).
| Model | Excavator | Weight | Max. torque | Cone diameter |
|---|---|---|---|---|
| S1 | 0.8 – 6 t | 106 kg | 2338 Nm | 200 mm |
| S2 | 1 – 6 t | 119 – 128 kg | 2338 – 4020 Nm | 200 mm |
| SG1 with grab | 1.5 – 6 t | 166 – 178 kg | 2338 – 2475 Nm | 200 mm |
| SB with planetary gearbox | 3 – 12 t | 240 kg | 12,000 Nm | 300 mm |
| SG3 with grab | 3.5 – 8 t | 400 kg | 2475 Nm | 245 mm |
| S2X | 6 – 10 t | 152 – 161 kg | 2338 – 4020 Nm | 245 mm |
| S1X | 6 – 18 t | 208 kg | 4020 Nm | 245 mm |
| SBX with planetary gearbox | 12 – 28 t | 620 kg | 30,000 Nm | 400 mm |
| SBXX with planetary gearbox | 25 – 40 t | 890 kg | 60,000 Nm | 400 mm |
- Compact cone splitters such as the S1 and S2 for mini excavators – see cone splitters for mini excavators.
- Cone splitters with planetary gearbox (SB, SBX, SBXX) for tough wood and large logs.
- Cone splitters with grab (SG1, SG3) for grabbing and splitting with one attachment.
Cone splitter or conventional log splitter?
| Cone splitter on an excavator | Conventional log splitter | |
|---|---|---|
| Principle | Rotating threaded cone | Hydraulic cylinder pushes the wood against a wedge |
| Drive | Excavator hydraulics | Own engine or PTO |
| Wood and machine | The attachment is moved to the log | The wood is brought to the machine |
| Carrier | Excavator or mini excavator required | Stands alone |
More in the guide log splitters for excavators.
Where are cone splitters used?
Cone splitters are used wherever an excavator is already at work and logs need to be broken down: in forestry, gardening and landscaping, tree care and clearing, on farms and in firewood processing. On some models other attachments can be run in place of the cone, such as an auger or a stump grinder.

Finding the right cone splitter
The operating weight and hydraulics of the excavator, the mount, and the type and quantity of wood are decisive. The guide Which cone splitter suits your excavator? takes you through the selection step by step. All models are listed under cone splitters for excavators; for a recommendation, use the contact page.
Frequently asked questions about cone splitters
What is a cone splitter?
A cone splitter is a log splitter that is mounted on an excavator or mini excavator as an attachment. A hydraulic motor turns a threaded splitting cone. The cone pulls itself into the wood and forces the log apart as its diameter increases.
What is a cone splitter called in German?
The German term is “Kegelspalter”. It is also described as “Holzspalter für Bagger” (log splitter for excavators).
Which excavators can use a cone splitter?
According to the technical data, BLACK SPLITTER cone splitters cover carrier machines from 0.8 to 40 tonnes – from the S1 for mini excavators to the SBXX for excavators from 25 to 40 tonnes.
How does a cone splitter differ from a conventional log splitter?
A conventional log splitter is stationary and pushes the wood against a wedge with a hydraulic cylinder; the wood is brought to the machine. A cone splitter hangs on the excavator arm and is moved to the log. It works with a rotating movement instead of a cylinder stroke.
Who manufactures cone splitters?
Black Splitter GmbH in Willingen (Hesse, Germany) develops and manufactures cone splitters in Germany. The range comprises nine models, including versions with planetary gearbox and with grab.
Note: this page explains the working principle. For mounting, operation and safe working, the documents for the specific attachment and carrier machine apply.