MT 6500 (3.87 cu.in)

OPERATION

64

Logs Under Stress (Fig. 64-65)

Make the first bucking cut (F) 1/3 of the way through the log and finish with a 2/3 cut (G) on the opposite side. As the log is being cut, it will tend to bend. The saw can become pinched or hung in the log if you make the first cut deeper than 1/3 of the diameter of the log.

Give special attention to logs under stress to prevent the bar and chain from pinching.

65

Types of Cutting Used

Overbucking (Fig. 66)

Begin on the top side of the log with the bottom of the saw against the log; exert light pressure downward.

Underbucking (Fig. 67)

Begin on the under side of the log with the top of the saw against the log; exert light pressure upward. During underbucking, the saw will tend to push back at you. Be prepared for this reaction and hold the saw firmly to maintain control.

66

WARNING: Never turn saw upside down to undercut.

The saw cannot be controlled in this position.

Always make your first cut on the compression side of the log. The compression side of the log is where

the pressure of the log’s weight is concentrated.

Limbing and Pruning

67

68

WARNING: Be alert for and guard against kickback.

Do not allow the moving chain to contact any other branches or objects at the nose of the guide bar when limbing or pruning. Allowing such contact can result in serious injury.

• Work slowly, keeping both hands on the saw with a firm and proper grip. Maintain secure footing and balance (Fig. 68).

• Keep the tree between you and the chain while limbing

(A, Fig. 69). Cut from the side of the tree opposite the branch you are cutting.

• Do not cut from a ladder, this is extremely dangerous (Fig. 68).

Leave this operation for professionals.

• Do not cut above chest height as a saw held higher is difficult to control against kickback.

• Be alert for springback. Watch out for branches that are bent or under pressure. Avoid being struck by the branch or the saw when the tension in the wood fibers is released.

• Keep a clear work area. Frequently clear branches out of the way to avoid tripping over them.

WARNING: Never climb into a tree to limb or prune.

Do not stand on ladders, platforms, a log or in any position which can cause you to lose your balance or control of the saw.

69

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OPERATION

70

Limbing Operation (Fig. 70-71)

• Always limb a tree after it is cut down. Only then can limbing be done safely and properly.

• Leave the larger limbs underneath the felled tree to support the tree as you work.

• Start at the base of the felled tree and work toward the top, cutting branches and limbs. Remove small limbs with one cut.

• Keep the tree between you and the chain. Cut from the side of the tree opposite the branch you are cutting.

• Remove larger, supporting branches with the cutting

techniques described in BUCKING WITHOUT A SUPPORT.

• Always use an overcut to cut small and freely hanging limbs.

Undercutting could cause limbs to fall and pinch the saw.

71

Pruning Operation (Fig. 72)

• When pruning trees it is important not to make the flush cut next to the main limb or trunk until you have cut off the limb further out to reduce the weight. This prevents stripping the bark from the main member.

• Underbuck the branch 1/3 through for your first cut, your second cut should overbuck to drop the branch off.

• Now make your finishing cut smoothly and neatly against the main member so the bark will grow back to seal the wound.

WARNING: If the limbs to be pruned are above chest height, hire a professional to perform the pruning.

72

Springpoles

A springpole (B, Fig. 73) is any log, branch, rooted stump, or sapling which is bent under tension by other wood so that it springs back if the wood holding it is cut or removed. On a fallen tree, a rooted stump has a high potential of springing back to the upright position during the bucking cut to separate the log from the stump. Watch out for springpoles. They are potentially dangerous.

WARNING: Springpoles are dangerous and could strike the operator, causing the operator to lose control of the chainsaw. This could result in severe or fatal injury to the operator.

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