Demonstration of the Huntly Hinge tree felling
Images courtesy of Tom Dunn, Forestry Commission Operations Supervisor based at Huntly.
The process of organised tree felling required a bench tree to be felled and held onto a high stump so that when other trees were felled across they were lying at a convenient thigh height for chainsaw snedding. The large trees in Clashindarroch had an unfortunate habit of breaking off the stump in this process and the bench tree advantage was frequently lost.
Roy Neish then foreman covering the Huntly felling team originated the idea of a tennon and slot for greater strength and with the team devised the system here demonstrated by Tom Dunn. This set of photographs in the PDF were a duplicate set which were sent as part of staff suggestion scheme for better methods and resulted in an award being presented to Roy.
The sequence shows Tom cutting the felling face of the bench tree, then the tennon, then cutting across the tree so as to leave the tennon intact and felling the tree with the help of a breaking bar and the tennon rising from its cut. The final few shots are of Tom removing the temporary felling hinge thus allowing the tennon to drop down securely into the slot which would withstand the massive forces as up to ten other trees were felled across it for snedding and processed into log and small roundwood products. In the third shot note that the bottom end of the tennon is sloped down towards the back so that when the tree tips forward the tennon’s front edge slips back easily without lifting the tree off its initial felling hinge.
Further and later refinements included making the tennon a more dovetailed shape thus preventing the pull out of the tennon.
Note the tools and safety gear used by Tom - Husqvarna chainsaw, breaking bar to assist tipping tree over, use as felling wedge and turning logs, loggers tape and pulp hook to lift and turn small logs (both carried on felling belt). Safety gear of helmet, visor, earmuffs, gloves and trousers with protective pads sewn onto the front of legs.
Groups: Forestry in Action, Northeast Scotland , Tools, equipment and clothing