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Open-face Technique

Making Sapwood Cuts

D =Felling Cut

Felling notch (C) – determines the direction of the fall

For an open-face cut:

NProperly place felling notch perpendicular to the line of fall, close to the ground.

NCut down at approx. 50° angle to a depth of approx.1/5 to 1/4 of the trunk diameter.

NMake second cut from below at approx. 40 degree angle.

NRemove resulting 90° piece.

001BA150 KN

NFor medium sized or larger trees make cuts at both sides of the trunk, at same height as subsequent felling cut.

NCut 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.

D

D

001BA144 KN

Conventional and open-face technique:

NBegin 1 to 2 inches (2,5 to 5 cm) higher than center of felling notch.

NCut horizontally towards the felling notch.

NLeave approx.1/10 of diameter uncut. This is the hinge.

NDo not cut through the hinge – you could lose control of the direction of the fall.

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.

MS 250

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STIHL MS 250 manual Open-face Technique Making Sapwood Cuts