Pushback:

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 drives the saw straight back toward the operator causing loss of saw control. Pushback fre- quently occurs when the top of the bar is used for cutting (fig. 14).

To avoid pushback

1.Be alert to forces or situafions 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 under buck cut (figures 25 to 27 and 33, pages 13 and 15), because the chain can pinch.

Pull-in:

Pull-inoccurs when the chain on the bottom of the bar is suddenly stopped. The chain on the bottom of the bar stops when it is pinched, caught or encounters a foreign object in the wood (seefig. 15).The reactionof the chain pulls the saw forward, causing the operator to lose control.

Pull-in frequently occurs when the spike bar of the saw is not held securely against the tree or limb and when the chain is not rotating at full speed before it contacts the wood.

To avoid pull-in

1.Always start a cut with the chain rotating at full speed and the spike bar in contact with the wood.

2.Pull-in may also be prevented by using plastic wedges to open the kerf or cut.

Cutting techniques

Felling

Felling is cutting down a tree.

Before felling a tree, consider carefully all conditions which may affect the direction of fall, including:

The intended direction of the fall.

The neutral lean of the tree.

Any unusually heavy limb structure.

Surrounding trees and obstacles.

The wind direction and speed.

WARN1NG!

Always observe the general condition of the tree. Look for decay and rot in the trunk. If it is rotted inside, it could snap and fall toward the operator while being cut.

Also lookfor broken or dead brancheswhich could vibrate loose and fall on the operator. When felling on a slope, the operator should stand on the up-hill side.

When felling in the vicinity of roads, railways and power lines, etc., take extra precautions (see fig. 16). Inform the police, utility company or railway authority before beginning to cut.

WARN1NG!

Useextremecautionwhen cuttingsmall size brush and saplings which may easily catch the chain and pull you off balance.

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Makita DCS 7301, DCS6401, DCS 7901, DCS 7300, DCS 6400 manual Pushback, To avoid pushback, To avoid pull-in, Felling, Pull-in

DCS 7301, DCS 7900, DCS 6400, DCS 7300, DCS 7901 specifications

Makita, a leading manufacturer of power tools, has a robust lineup of professional-grade chainsaws, including the DCS 7900, DCS 7901, DCS 7300, DCS 7301, and DCS 6401 models. Each chainsaw is designed with advanced technology to meet the demanding needs of forestry and construction professionals.

The Makita DCS 7900 is a powerful chainsaw equipped with a 79cc engine that delivers high cutting performance. It features a lightweight design combined with a powerful engine, allowing for maximum maneuverability. The saw's decompression valve ensures easy starting, while the adjustable chain oiler provides lubrication tailored to various cutting conditions. Its anti-vibration technology minimizes user fatigue during prolonged use, making it an excellent choice for professionals.

The DCS 7901 is an enhanced version of the DCS 7900, featuring an electronically controlled ignition system that optimizes fuel combustion for increased efficiency and lower emissions. This model maintains the same robust power but with improved fuel economy, making it an environmentally friendly option without sacrificing performance. The DCS 7901 also includes a heavy-duty air filter system, ensuring longer operation times by extending the life of the engine.

The DCS 7300 and DCS 7301 models are mid-range chainsaws that deliver exceptional power and versatility. The DCS 7300 features a 73cc engine, offering a perfect balance of weight and power, ideal for both felling and limbing. The DCS 7301 shares similar specifications with the DCS 7300 but includes additional features such as a tool-less chain adjustment system and a larger fuel tank for increased run time. Both models come with advanced anti-vibration technologies that ensure smooth operation.

Finally, the Makita DCS 6401 is a compact yet powerful chainsaw designed for users who require maneuverability without compromising on power. Equipped with a 64cc engine, this chainsaw is suitable for a variety of cutting tasks. It features a lightweight construction, making it ideal for prolonged use in tight spaces. The DCS 6401 also has a high-performance air filtration system, which increases engine life and efficiency.

In summary, all Makita chainsaws in this lineup are designed with user comfort and efficiency in mind. With powerful engines, advanced technology, and robust features, the DCS 7900, DCS 7901, DCS 7300, DCS 7301, and DCS 6401 ensure reliability and performance for professional users in demanding environments.