The Wood Duck: A New Tree Falling Tool

Lyons, Kevin; Ewart, J. C.

doi:10.5849/wjaf.11-026

Cited by 3 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These include engineered safety controls, improvement in organizational policies and management practices or improvement in working conditions. For example, the use of hydraulic wedges that are remotely operated removes fallers from the immediate area of a falling tree (26,27). Improvements in work conditions such as limiting the number of hours worked per day, including travel time to a worksite, could reduce faller fatigue.…”

Section: Mcleod Et Almentioning

confidence: 99%

Prevention in dangerous industries: does safety certification prevent tree-faller injuries?

McLeod¹,

Sarkany²,

Davies³

et al. 2015

Scand J Work Environ Health

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Mcleod Et Almentioning

confidence: 99%

Prevention in dangerous industries: does safety certification prevent tree-faller injuries?

McLeod¹,

Sarkany²,

Davies³

et al. 2015

Scand J Work Environ Health

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is not the cross sectional area of the strap (Fig.3) that determines its strength, the important area is the face extending from the inside edge of the weakening cut up to the backcut; the strap fails in shear along this face. Refer to Lyons (2013) for a video describing the mechanics of the strap. Thus, For personal use only.…”

Section: Discussionmentioning

confidence: 99%

“…These results indicate the second prototype is losing less than 30% of the separation force to driveline friction as opposed to the first prototype which lost 50%; this is a significant improvement over the first prototype. For the first prototype F s can be estimated by equation (4) from Lyons and Ewart (2012). Comparing F s produced by the first prototype to the second, it can be seen that the F s produced by the second prototype is 4.7 times greater when T in = 30Nm and 3.4 times greater when T in = 60Nm.…”

Section: Separation Forcementioning

confidence: 99%

“…The strength of the strap is most strongly controlled by the distance between the backcut and the weakening cut. Refer to Lyons (2013) for a YouTube video demonstrating the use of the second prototype developed in this study.…”

Section: Field Testingmentioning

confidence: 99%

“…The hydraulic flange spreader was found to be limited by the separation force it could produce and the hydraulic hoses were awkward to manage in the forest. Lyons and Ewart (2012) developed a scissor jack that could be driven by an electric drill (the first prototype) to initiate falling when using the new system of falling cuts. The first prototype produced 15.7 kN (kilonewtons) of separation force given an input torque of 30 Nm (newtonmetres).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

New development of a remotely operated falling wedge

Kevin

2015

The Forestry Chronicle

View full text Add to dashboard Cite

A series of projects has developed an alternate cutting pattern that prevents a tree from moving while the faller is cutting at the base and a tool to initiate falling once the faller is in the clear. This specific project developed a second prototype of a remotely operated wedge for use when manually falling trees. The second prototype reduced the friction in the drive train and increased the mechanical advantage, and this increased the separation force produced for a given input torque by a multiple of approximately four, depending on the magnitude of the input torque. In this project, success means the tree did not begin to displace until the remotely operated wedge was inserted and activated. When using the second prototype and permitting the faller to vary the cutting pattern depending on tree imbalance, the success rate was increased from 91% when using the first prototype to 98%. Further testing is required in larger timber and with other fallers to determine if the high success rate can be maintained in these conditions.

show abstract

Tree Felling with a Drill Cone

Knobloch,

Richter,

Erle

2023

Croat. j. for. eng. (Online)

View full text Add to dashboard Cite

Motor-manual timber felling is one of the most dangerous operations in the forest and cannot be completely replaced by fully mechanized timber harvesting by a harvester when dealing with large and deciduous trees. Shifting the center of gravity of tree ready to be felled beyond its tipping line using conventional felling wedges is dangerous because the forest worker is directly behind the stem and under the tree crown until just before the tree falls. The worker can be hit by the trunk itself, but also by falling parts of the crown. In a preliminary study for the development of a new type of felling head, felling with a drill cone that can open the felling cut with the help of an applied torque was investigated. A drill cone does not require any special cutting technique, no counter forces to the tree, works without impulses, it is self-retaining and can be unscrewed again.In order to determine the torque required for felling the tree as a function of the tree parameters, the mathematical equation framework was established and practical experiments were used to determine the friction parameters and verify the calculations. The torque of the drill cone is used to bend the intact fibers of the hinge, shift the center of gravity of the tree in the direction of fall, and to overcome the friction of the drill cone on the felling cut. The effects of forward or backward leaning trees on the required torque can also be quantified. It has been shown that the efficiency of a drill cone is low, but this is compensated for by the high internal torque to lift ratio. The maximum measured input torque for felling trees with a felling diameter up to 55 centimeter was 100 Nm.

show abstract

The Wood Duck: A New Tree Falling Tool

Cited by 3 publications

References 0 publications

Prevention in dangerous industries: does safety certification prevent tree-faller injuries?

Prevention in dangerous industries: does safety certification prevent tree-faller injuries?

New development of a remotely operated falling wedge

Tree Felling with a Drill Cone

Contact Info

Product

Resources

About