Secateurs
They are usually operated with two hands, and with handles typically between 30 centimetres (12 in) & 91 centimetres (36 in) long to give good leverage. Some have telescopic handles which can be extended to a length of two metres, in order to increase leverage and to reach high branches on a tree. Loppers are mainly used for the pruning of tree branches with diameters less than 5 centimetres (2 in). Some of the newer lopper designs have a gear or compound lever system which increases the force applied to the blades, or a ratchet drive.
Construction
The main distinction among loppers is between bypass and anvil types. Bypass loppers operate like scissors, except that they generally only have one blade that moves past a jaw or hook that has an approximately square edge that is not typically sharpened and is usually concave or hook shaped in order keep branches from slipping out of the jaws. The jaws of bypass loppers may be straight, curved, or one curved with one straight. Anvil loppers have a single sharpened blade, with a straight or sometimes curved edge, that closes against a similarly contoured flat anvil like surface on the other side of the jaws, usually made of a softer metal than the blade.
Anvil loppers have the disadvantage of tending to crush rather than cut, sometimes leaving an untidy wound, more vulnerable to infection. Their main advantages are of relative strength and of being less likely to jam with fibrous material. Very hard or resilient branches can sometimes deflect a bypass lopper so that material either binds between the blades or even levers them apart, which can be dangerous both to the tool and the operator.
Both types of lopper generally have a sprung adjusting screw at the fulcrum, which can be used to tighten the blades as they loosen in use. With bypass loppers, it is also useful for releasing material jamming the blades. Anvil loppers usually have a screw for adjusting or detaching the plate, so that it can be moved to compensate for wear or replaced entirely.
They are usually operated with two hands, and with handles typically between 30 centimetres (12 in) & 91 centimetres (36 in) long to give good leverage. Some have telescopic handles which can be extended to a length of two metres, in order to increase leverage and to reach high branches on a tree. Loppers are mainly used for the pruning of tree branches with diameters less than 5 centimetres (2 in). Some of the newer lopper designs have a gear or compound lever system which increases the force applied to the blades, or a ratchet drive.
Construction
The main distinction among loppers is between bypass and anvil types. Bypass loppers operate like scissors, except that they generally only have one blade that moves past a jaw or hook that has an approximately square edge that is not typically sharpened and is usually concave or hook shaped in order keep branches from slipping out of the jaws. The jaws of bypass loppers may be straight, curved, or one curved with one straight. Anvil loppers have a single sharpened blade, with a straight or sometimes curved edge, that closes against a similarly contoured flat anvil like surface on the other side of the jaws, usually made of a softer metal than the blade.
Anvil loppers have the disadvantage of tending to crush rather than cut, sometimes leaving an untidy wound, more vulnerable to infection. Their main advantages are of relative strength and of being less likely to jam with fibrous material. Very hard or resilient branches can sometimes deflect a bypass lopper so that material either binds between the blades or even levers them apart, which can be dangerous both to the tool and the operator.
Both types of lopper generally have a sprung adjusting screw at the fulcrum, which can be used to tighten the blades as they loosen in use. With bypass loppers, it is also useful for releasing material jamming the blades. Anvil loppers usually have a screw for adjusting or detaching the plate, so that it can be moved to compensate for wear or replaced entirely.
Available in PTFE coating on blades
Available in lightweight wood handles
Available in strong and durable steel handles with comfort non-slip soft grip
Unique telescopic handles which allow extended reach and excellent cutting leverage
Precision made pivot bolt provides smooth cutting action
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