OPERATION

BUCKING Logs Under Stress

See Figures 19 - 20.

When the log is supported along its entire length, it should be cut from the top or overbucking.

When the log is supported on one end, cut 1/3 the diameter from the underside or underbucking. Then make the finishing cut by overbucking to meet the first cut.

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.

When bucking on a slope, always stand on the uphill side of the log as shown in figure 18. When “cutting through,” to maintain complete control of the chain saw, release the cutting pressure near the end of the cut without relaxing your grip on the chain saw handles. Do not let the chain contact the ground. After completing the cut, wait for the saw chain to stop before you move the chain saw. Always stop the

motor before moving from tree to tree.

Types of Cutting Used

See Figure 20.

Overbucking

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

the saw will tend to pull away from you.

Underbucking

Begin on the under side of the log with the top of the saw against the log; exert light pressure upward. During under- bucking, the saw will tend to push back at you. Be pre-

pared for this reaction and hold the saw firmly to maintain control.

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.

Log Supported at One End:

LOAD

finishing cut

1st CUT

1/3 Dia

Log Supported at Both Ends:

LOAD

1st CUT 1/3 Dia

FINISHING CUT

Fig. 19

 

Overbucking

 

Underbucking

Fig. 20

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Image 17
Ryobi P540B manual Bucking Logs Under Stress, Types of Cutting Used, See Figures 19