Zenoah GZ7000 manual Directional cuts, Felling cut

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WORKING TECHNIQUES

Felling

WARNING! Unless you have special ! training we advise you not to fell trees

with a diameter larger than the bar length of your saw!

Felling is done using three cuts. First you make the directional cuts, which consist of the top cut and the bottom cut, then you finish with the felling cut. By placing these cuts correctly you can control the felling direction very accurately.

Directional cuts

To make the directional cuts you begin with the top cut. Stand to the right of the tree and cut on the pull stroke.

Next make the bottom cut so that it finishes exactly at the end of the top cut.

The directional cuts should run 1/4 of the diameter through the trunk and the angle between the top cut and bottom cut should be 45°.

The line where the two cuts meet is called the directional cut line. This line should be perfectly horizontal and at right angles (90°) to the chosen felling direction.

Felling cut

The felling cut is made from the opposite side of the tree and it must be perfectly horizontal. Stand on the left side of the tree and cut on the pull stroke.

Make the felling cut about 3-5 cm (1.5-2 inches) above the bottom directional cut.

Set the spike bumper (if one is fitted) just behind the felling hinge. Use full throttle and advance the chain/bar slowly into the tree. Make sure the tree does not start to move in the opposite direction to your intended felling direction. Drive a wedge or breaking bar into the cut as soon as it is deep enough.

Finish the felling cut parallel with the directional cut line so that the distance between them is at least 1/10 of the trunk diameter.The uncut section of the trunk is called the felling hinge.

The felling hinge controls the direction that the tree falls in.

All control over the felling direction is lost if the felling hinge is too narrow or non-existent, or if the directional cuts and felling cut are badly placed.

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Contents Operator’s manual Symbols on the machine KEY to SymbolsSymbols in the operator’s manual Contents What is what on the chain saw? What is WHAT?Before using a new chain saw General Safety PrecautionsAlways use common sense Personal protective equipment Machine′s safety equipmentChain brake and front hand guard General Safety Precautions Chain catcher Throttle lockoutRight hand guard Vibration damping systemCutting equipment Stop switchMuffler General rulesBar Cutting equipment designed to reduce kickbackChain Injuries Some terms that describe the bar and chainGeneral information on sharpening cutting teeth Sharpening your chain and adjusting depth gauge settingTensioning the chain Which could lead to serious, even fatal injuries Chain oil Lubricating cutting equipmentFilling with chain oil Checking chain lubricationNeedle bearing lubrication Chain drive sprocketChecking wear on cutting equipment Fitting the bar and chain AssemblyFitting a spike bumper Protect your hands from injuryFuel Fuel HandlingFuelling Fuel safetyTransport and storage Long-term storageStarting and stopping Starting and StoppingCold engine Warm engineStopping Working Techniques Basic safety rulesBefore use General working instructionsGeneral rules Terms Basic cutting techniqueLimbing Safe distance Tree felling techniqueFelling direction Clearing the trunk and preparing your retreatFelling cut Directional cutsFreeing a tree that has fallen badly General adviceFreeing a trapped tree Cutting trees and branches that are in tensionWhat is kickback? How to avoid kickbackCutting the trunk into logs Carburettor adjustment MaintenanceGeneral High speed jet H Correctly adjusted carburettorChecking brake band wear Checking the front hand guardImmediately Checking the inertia brake releaseMuffler Changing a broken or worn starter cord StarterTensioning the recoil spring Changing a broken recoil springSpark plug Air filterLubricating the bar tip sprocket Must always be replacedDust Free centrifugal cleaning Adjustment of the oil pumpRunning when making adjustments Needle bearing lubricationWinter use Temperature 0C or colderFitting the winterising kit Daily maintenance Weekly maintenance Monthly maintenance Maintenance scheduleTechnical data Technical DataSaw chain filing and file gauges EC-declaration of conformity Bar and chain combinationsApplies to Europe only EN ISO 12100-22003, Cispr 122005, EN ISOLimited warranty Limited Warranty1151332-26