Stimmen - 5, Durchschnittliche Bewertung: 3.6
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Anleitung Zusammenfassung
2 Make sure the object you are cutting will not split. 3 Make sure the chain will not strike the ground or any other object during or after cutting. 4 Is there a risk of kickback? 5 Do the conditions and surrounding terrain affect how safely you can stand and move about? Two factors decide whether the chain will jam or the object that you are cutting will split: the first is how the object is supported before and after cutting, and the second is whether it is in tension. English – 25 WORKING TECHNIQUES In most cases you can avoid these problems by cutting in two stages; from the top and from the bottom.You need to support the object so that it will not trap the chain or split during cutting. ! WARNING! If the chain jams in the cut: stop the engine! Don’t try to pull the chain saw free. If you do you may be injured by the chain when the chain saw suddenly breaks free. Use a lever to open up the cut and free the chain saw. The following instructions describe how to handle the common situations you are likely to encounter when using a chain saw. Cutting The log is lying on the ground. There is little risk of the chain jamming or the object splitting. However there is a risk that the chain will touch the ground when you finish the cut. Cut all the way through the log from above. Avoid letting the chain touch the ground as you finish the cut. Maintain full throttle but be prepared for what might happen. - If it is possible (can you turn the log?) stop cutting about 2/3 of the way through the log. -Turn the log and finish the cut from the opposite side. The log is supported at one end. There is a high risk that it will split. Start by cutting from below (about 1/3 of the way through). - Finish by cutting from above so that the two cuts meet. The log is supported at both ends. There is a high risk that the chain will jam. - Start by cutting from above (about 1/3 of the way through). - Finish by cutting from below so that the two cuts meet. Limbing When limbing thick branches you should use the same approach as for cutting. Cut difficult branches piece by piece. 26 – English WORKING TECHNIQUES Felling technique for tree tops ! WARNING! It takes a lot of experience to fell a tree. Inexperienced users of chain saws should not fell trees. Do not attempt any task beyond your experience level! Safe distance During tree maintenance work above ground level, the working area must always be secured and marked out with signs, tape or the like.The safe distance between the top of the tree that is to be felled and the nearest workplace must be at least 2 1/2 times the height of the tree. Make sure that no-one else is in this risk zone before or during felling. Felling direction The aim is to fell the tree in a position where you can limb and cross-cut the log as easily as possible.You want it to fall in a location where you can stand and move about safely. The main thing to avoid is that the falling tree top should get jammed in another tree.Taking down a ”jammed” tree top is very dangerous (see point 4 in this section). Once you have decided which way you want the top of the tree to fall you must assess which way the top of the tree would fall naturally. Several factors affect this: • Lean of the tree • Bend • Wind direction • Arrangement of branches • Weight of snow You may find you are forced to let the tree-top fall in its natural direction because it is impossible or dangerous to try to make it fall in the direction you first intended. Another very important factor, which does not affect the felling direction but does affect your safety, is to make sure the tree has no damaged or dead branches that might break off and hit you during felling. ! WARNING! During critical felling operations, hearing protectors should be lifted immediately when sawing is completed so that sounds and warning signals can be heard. Topping a tree Topping a tree 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.Try to take your position in the tree on the right side 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. English – 27 WORKING TECHNIQUES Felling cut The felling cut is made from the opposite side of the tree and it must be perfectly horizontal. Try to take a correct position so you are able to cut on the pull stroke. Make the felling cut about 1.5-2 inches (3-5 cm) above the bottom directional cut. Use full throttle and bring the ...