Vertical Log Splitter: How Many Tonnes by Diameter and Species

A 14 t vertical log splitter handles oak and beech up to Ø 250 mm, spruce and poplar up to Ø 300 mm. Below 7 t the limit drops under 250 mm even on clean wood. Our catalogue carries 12 Güde and Bernardo models, from €311 to €2,736. Official distributor since 2007.

The vertical log splitter keeps the log on the ground and brings the wedge down from above. The horizontal one requires lifting the round onto a work surface.

The difference comes down to weight. A beech round of Ø 400 mm and 50 cm in length weighs over 40 kg: lifting it dozens of times a day is not sustainable. The vertical machine removes the lifting, and that is why it dominates professional use, where volumes are handled continuously.

The horizontal machine remains a tool for short lengths and modest diameters. Anyone working wood already cut under 25 cm in diameter finds it quicker, because the log stays in place and does not need repositioning.

An operating rule of thumb: if the average diameter of your rounds exceeds 30 cm, or if you split more than 20 quintals of wood per season, the vertical machine is the only configuration that holds up. In Italy 16.0% of households use firewood (ISTAT, Dotazioni energetiche delle famiglie 2024), around 3.86 million households: the market for those producing wood for resale is large and works at volumes the horizontal bed cannot sustain.

The splitting force required depends on three variables: log diameter, species and the presence of knots. None of the three is enough on its own to decide.

Manufacturers declare maximum diameter using different criteria, and that creates confusion. Bernardo distinguishes the figure by species. Güde declares a single maximum machine diameter. On the 14 t model the gap is wide: Bernardo states 250 mm on hardwood, Güde states 430 mm without specifying the species. The first figure describes repeatable work, the second the dimensional capacity of the column.

The hardwood figures come from Bernardo's declarations per model; the Güde figures from the manufacturer's rating plate data. On knotty rounds a practical rule recurs in every comparison between operators: a knot doubles the resistance compared with the straight trunk of the same species. A 9 t machine stalls where the branches split off, while the same wood in a clean section passes without effort.

Oversizing is not waste. Anyone working oak and beech for resale chooses above 16 t not for the diameter, but to avoid stopping the cycle on every difficult round. The price of dry wood (M20-25%) stood at €279.3/t in September 2024 according to the Osservatorio AIEL-CIA: every machine stoppage is lost margin.

The power supply determines where you can work, not how much you split. The three systems cover different scenarios.

230 V single-phase. Plugs into a domestic socket. Power stops at around 3 kW, which in practice caps the machine between 12 and 13 t. In the catalogue this covers the GHS 370/4TE (€311), GHS 500/6,5TE (€419) and GHS 500/6TE (€602). It is the choice for anyone working in premises without an industrial supply.

400 V three-phase. Requires an industrial connection and supports motors from 3.5 to 5.5 kW with constant torque under continuous load. The Bernardo HS 14 E (€1,092, 3.5 kW) and the Güde GHS 1000/14TE-A (€1,243, 4.3 kW) belong here. It suits anyone with a shed or workshop splitting on a continuous cycle.

Power take-off. The machine draws power from the tractor through a PTO shaft at 540 rpm and a three-point linkage. No mains supply is needed, so you can work in the forest or in the field. The Güde GHS 1000/14TZ-A (€1,279) requires a tractor of 18 to 25 kW, the GHS 1000/20TEZ-A one of 22 to 30 kW. The Bernardo HS 30 Z (€2,538) runs on the PTO shaft only.

Combined. Electric motor and PTO shaft on the same machine. It covers the case of splitting at the yard in winter and taking the machine into the forest during felling. Bernardo HS 16 ZE (€2,031) and HS 30 ZE (€2,657), Güde GHS 1000/14TEZ-A (€1,609) and GHS 1000/20TEZ-A (€2,736).

The 2020 ISTAT agricultural census counts 268,532 farms with adjoining woodland, across 2,864,890 hectares. For this audience the combined machine removes the mains-supply constraint without giving up stationary use.

Cycle time is the sum of advance, cut and wedge return. Bernardo declares 8-15 seconds on rounds of Ø 200-300 mm, broken down into 3-5 s of advance, 2-5 s of cutting and 3-5 s of return.

Güde does not declare the cycle in seconds but the ram speeds: on the GHS 1000/14TE-A the rapid advance is 0.20 m/s, the slow advance 0.038 m/s and the return 0.047 m/s. With a 960 mm stroke, the full cycle has to be calculated from the speeds; it is not printed on the datasheet.

The twin hydraulic pump shortens dead time: the ram travels fast until it meets the wood, then the second pump disengages, speed halves and pressure rises. The gain is in the idle stroke, which on a 960 mm cylinder accounts for most of the cycle.

Beware of misreading the figure. An 8-second cycle does not produce twice as much as a 16-second one if the bottleneck is handling the round. Above 400 mm in diameter, positioning time exceeds splitting time, and the integrated log lifter, fitted across the whole Bernardo range, affects productivity more than the cylinder does.

Wedge log splitters fall under the UNI EN 609-1 standard, which sets out the safety requirements for these agricultural and forestry machines.

The standard requires three elements. Two-hand hold-to-run control, which requires both controls to be held down throughout the hazardous stroke and stops movement as soon as one is released. Guards against contact and flying splinters. Automatic return of the wedge when the control is released. The intended field of use is one operator at a time.

On marking, the Machinery Directive 2006/42/EC is transposed in Italy by D.Lgs. 27 gennaio 2010 n. 17. One point to bear in mind when buying: Regulation (EU) 2023/1230 replaces the directive with effect from 20 January 2027, with no optional coexistence period. Machines placed on the market from that date must already comply with the new text.

Anyone using a log splitter in a business has further obligations. D.Lgs. 81/2008 classifies the machine as work equipment (art. 69) and requires the employer to provide compliant equipment (art. 70), documented periodic inspections (art. 71) and operator information and training (art. 73). Risk assessment and the supply of PPE are added to that.

Every model in the table is a vertical column splitter. The full range is in the column log splitters collection; the Austrian models with an integrated log lifter are on the Bernardo page, the German ones with a KAT 1 three-point linkage on the Güde page.

Sandra Gaspar's advice

If you split oak or beech for resale, do not go below 16 t. I have seen too many customers come back after two seasons because their 10 t machine stalled on every knotty round. The price gap between a 14 t and a combined 16 t pays for itself in one season of stoppages avoided.

It depends on diameter and species. For spruce and poplar up to Ø 300 mm, 6-7 t is enough. For oak and beech of the same diameter you need 14 t. Above 400 mm of hardwood the benchmark is 16 t (Bernardo HS 16 ZE, €2,031), beyond 500 mm it is 30 t.

The vertical machine works the log resting on the ground with the wedge coming down from above, so no lifting is needed. The horizontal one forces you to load the round onto a bed. Above 30 cm in diameter a round weighs more than 40 kg: the vertical machine is the only sustainable configuration at continuous volumes.

Single-phase 230 V is the ordinary domestic socket and supports motors up to about 3 kW, which caps the machine at 12-13 t. Three-phase 400 V requires an industrial connection and supports 3.5-5.5 kW with constant torque under continuous load, which is what repeated-cycle work needs.

Before assuming a fault, check the level and condition of the hydraulic oil and the setting of the relief valve. If force drops progressively, the most common cause is wear on the pump or the cylinder seals. On machines with years of work behind them, overhauling the pump and cylinder restores the rated pressure.

The factor that weighs most is not moisture but grain. A straight, clean round opens with less force in either condition, while a knotty one resists regardless. Common practice is to split after cutting and season the wood already split, because it dries faster.

Sources: ISTAT, Dotazioni energetiche delle famiglie 2024 (published 9 October 2025); ISTAT, 7° Censimento generale dell'agricoltura 2020; Osservatorio AIEL-CIA, price survey September 2024; Bernardo and Güde technical datasheets; UNI EN 609-1; D.Lgs. 17/2010; Regulation (EU) 2023/1230; D.Lgs. 81/2008.