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2. The risk of pull-in may also be reduced by using wedges to open the kerf or cut. Pushback occurs when the chain on the top of the bar is suddenly stopped when it is pinched, caught or encounters a foreign object in the wood. The reaction of the chain may drive the saw rapidely straight back toward the operator and may cause loss of saw control. Pushback frequently occurs when the top of the bar is used for cutting. To avoid pushback 1. Be alert to forces or situations that may cause material to pinch the top of the chain. 2. Do not cut more than one log at a time. 3. Do not twist the saw when withdrawing the bar from a plunge cut or underbuck cut because the chain can pinch. MS 290, MS 310, MS 390 English Felling Instructions: Buttress roots When felling, maintain a distance of at 001BA040 KN A45° 45° If the tree has large buttress roots, cut least 2 1/2 tree lengths from the nearest into the largest buttress vertically first person. (horizontally next) and remove the 001BA146 KN 001BA088 LA2/12 1 1/12 resulting piece. When felling in the vicinity of roads, railways and power lines, etc., take extra precautions. Inform the police, utility company or railway authority before beginning to cut. Escape path !Warning! Gunning sight 001BA153 KN When making the felling notch, use the gunning sight on the shroud and housing First clear the tree base and work area The noise of your engine may drown any from interfering limbs and brush and warning call. clean its lower portion with an ax. Then, establish two paths of escape (B) and remove all obstacles. These paths should be generally opposite to the planned direction of the fall of the tree (A) and about at a 45° angle. Place all tools and equipment a safe distance away from the tree, but not on the to check the desired direction of fall: escape paths. Position the saw so that the gunning sight points exactly in the direction you want the tree to fall. MS 290, MS 310, MS 390 English 001BA143 KN C C 001BA143 KN C C 001BA150 KN Conventional cut C = felling notch - determines the direction of the fall For a conventional cut: : Properly place felling notch perpendicular to the line of fall, close to the ground. : Cut down at app. 45-degree angle to a depth of about 1/5 to 1/4 of the trunk diameter. : Make second cut horizontal. : Remove resulting 45-degree piece. Open-face technique C = felling notch - determines the direction of the fall For an open-face cut: : Properly place felling notch perpendicular to the line of fall, close to the ground. : Cut down at app. 50-degree angle to a depth of app.1/5 to 1/4 of the trunk diameter. : Make second cut from below at app. 40 degree angle. : Remove resulting 90-degree piece. Making sapwood cuts : For medium sized or larger trees make cuts at both sides of the trunk, at same height as subsequent felling cut. : Cut to no more than width of guide bar. This is especially important in softwood in summer - it helps prevent sapwood splintering when the tree falls. MS 290, MS 310, MS 390 English 001BA144 KN D D Drive wedges into the felling cut where necessary to control the fall. !Warning! If the tip of the bar contacts a wedge, it may cause kickback. Wedges should be of wood or plastic - never steel, which can damage the chain. 001BA145 KN E E D = Felling cut E = Hinge Conventional and open-face technique: : Helps control the falling tree. : Begin 1 to 2 inches (2,5 to 5 cm) : Do not cut through the hinge – you higher than center of felling notch. could lose control of the direction of the fall. : Cut horizontally towards the felling notch. : Leave approx.1/10 of diameter uncut. This is the hinge. : Do not cut through the hinge - you could lose control of the direction of the fall. MS 290, MS 310, MS 390 English 1 4 2 001BA147 KN 001BA148 KN Felling cut for small diameter trees: simple fan cut Engage the bumper spikes of the chainsaw directly behind the location of the intended hinge and pivot the saw around this point only as far as the hinge. The bumper spike rolls against the trunk. Felling cut for large diameter trees: !Warning! Felling a tree that has a diameter greater than the length of the guide bar requires use of either the sectioning felling cut or plunge-cut method. These methods are extremely dangerous because they involve the use of the nose of the guide bar and can result in kickback. Only properly trained professionals should attempt these techniques. Sectioning method For the sectioning method make the first part of the felling cut with the guide bar fanning in toward the hinge. Then, using the bumper spike as a pivot, reposition the saw for the next cut. Avoid repositioning the saw more than necessary. When repositioning for the next cut, keep the guide bar fully engaged in the kerf to keep the felling cut straight. If the saw begins to pinch, insert a wedge to open the cut. On the last cut, do not cut the hinge. MS 290, MS 310, MS 390 English Plunge-cut method Timber having a diameter more than twice the lengt...

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