Zenoah GZ7000 manual Freeing a tree that has fallen badly, Freeing a trapped tree, General advice

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WORKING TECHNIQUES

When the felling cut and directional cut are complete the tree should start to fall by itself or with the aid of a felling wedge or breaking bar.

We recommend that you use a bar that is longer than the diameter of the tree, so that you can make the felling cut and directional cuts with single cutting strokes. See instructions under the heading Technical data section to find out which lengths of bar are recommended for your saw.

There are methods for felling trees with a diameter larger than the bar length. However these methods involve a much greater risk that the kickback zone of the bar will come into contact with the tree.

Freeing a tree that has fallen badly

Freeing a ”trapped tree”

It is very dangerous to remove a trapped tree and there is high accident risk.

Never try to fell the tree that is trapped.

Never work in the risk zone of the hanging trapped tree.

The safest method is to use a winch.

Tractor-mounted

Portable

Cutting trees and branches that are in tension

Preparations:Work out which side is in tension and where the point of maximum tension is (i.e. where it would break if it was bent even more).

Decide which is the safest way to release the tension and whether you are able to do it safely. In complicated situations the only safe method is to put aside your chain saw and use a winch.

General advice:

Position yourself so that you will be clear of the tree or branch when the tension is released.

Make one or more cuts at or near the point of maximum tension. Make as many cuts of sufficient depth as necessary to reduce the tension and make the tree or branch break at the point of maximum tension.

Never cut straight through a tree or branch that is in tension!

26 – English

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Contents Operator’s manual Symbols in the operator’s manual KEY to SymbolsSymbols on the machine Contents What is WHAT? What is what on the chain saw?Always use common sense General Safety PrecautionsBefore using a new chain saw Chain brake and front hand guard Machine′s safety equipmentPersonal protective equipment General Safety Precautions Right hand guard Throttle lockoutChain catcher Vibration damping systemMuffler Stop switchCutting equipment General rulesChain Cutting equipment designed to reduce kickbackBar Injuries Some terms that describe the bar and chainSharpening your chain and adjusting depth gauge setting General information on sharpening cutting teethTensioning the chain Filling with chain oil Lubricating cutting equipmentWhich could lead to serious, even fatal injuries Chain oil Checking chain lubricationChecking wear on cutting equipment Chain drive sprocketNeedle bearing lubrication Fitting a spike bumper AssemblyFitting the bar and chain Protect your hands from injuryFuel Handling FuelTransport and storage Fuel safetyFuelling Long-term storageCold engine Starting and StoppingStarting and stopping Warm engineStopping Before use Basic safety rulesWorking Techniques General working instructionsGeneral rules Basic cutting technique TermsLimbing Felling direction Tree felling techniqueSafe distance Clearing the trunk and preparing your retreatDirectional cuts Felling cutFreeing a trapped tree General adviceFreeing a tree that has fallen badly Cutting trees and branches that are in tensionCutting the trunk into logs How to avoid kickbackWhat is kickback? General MaintenanceCarburettor adjustment Checking brake band wear Correctly adjusted carburettorHigh speed jet H Checking the front hand guardChecking the inertia brake release ImmediatelyMuffler Tensioning the recoil spring StarterChanging a broken or worn starter cord Changing a broken recoil springLubricating the bar tip sprocket Air filterSpark plug Must always be replacedRunning when making adjustments Adjustment of the oil pumpDust Free centrifugal cleaning Needle bearing lubricationFitting the winterising kit Temperature 0C or colderWinter use Maintenance schedule Daily maintenance Weekly maintenance Monthly maintenanceTechnical Data Technical dataApplies to Europe only Bar and chain combinationsSaw chain filing and file gauges EC-declaration of conformity EN ISO 12100-22003, Cispr 122005, EN ISOLimited Warranty Limited warranty1151332-26