If you have never needed to look for a boat propeller in the past, and have only started out, all the jargon that is associated with a boat prop can leave you quite confused. However, once youve familiarized yourself with the associated language, looking for a boat prop can be quite easy.
The parts of a boat prop: The normal boat propeller is made of either three or four blades which surround the hub. The hub, in turn, connects the blades of the propeller to the engines drive shaft. The blades are angled in the way that enables them to screw through water, thereby moving the boat ahead. The leading edge refers to the end of the blade that cuts through water, and the opposite side is referred to as the trailing edge.
A spline, while technically, is not a part of the propeller, refers to the drive shafts teeth. Hubs are designed in a way that allows them to fit shafts with given numbers of splines.
The features of a boat prop: Boat props are classified by their diameter and pitch, and this is often displayed as 2 numbers (in inches), such as 15.5 X 12. One can usually find this stamped on the props hub. The 1st number refers to the props diameter (which would be double the distance from the blades end to the hubs center). The 2nd number refers to the props pitch. The pitch refers to the distance that the propeller can theoretically travel through with every revolution. A prop with a 12 inch pitch could travel around 1 foot with a single revolution. Pitch is often looked upon as a theoretical figure because a prop pitch can experience slips in varied real world scenarios. A slip refers to the difference in ratio between the actual distance that is traveled and the props given pitch. This slip can be varied under similar conditions, an example being that an efficiently planned boat could experience only a 10 percent slip, where as a heavy work boat could experience as much as 80 percent slip.
Rotation of a propeller can be right or left hand, and most boat propellers come with right hand rotation. Left handed rotation is generally found aboard boats that require heavy steering wherein the motors torque is countered using double engines.
A cupped blade refers to the special treatment wherein the prop blades trailing edge is curved. This helps increase performance levels under specific conditions.
The rake refers to the blades angle from the hub. A negative rake indication shows that the blades are pointed forward (towards the boats front), and this is generally done to strengthen high end props.
Before you start, it is important that you note down your engines specifications, such as make, horse power (HP), model, etc. and your existing props details like its material (steel, aluminum, etc), diameter, pitch, and number of blades. You can then comfortably embark upon your hunt for a new boat prop.
The parts of a boat prop: The normal boat propeller is made of either three or four blades which surround the hub. The hub, in turn, connects the blades of the propeller to the engines drive shaft. The blades are angled in the way that enables them to screw through water, thereby moving the boat ahead. The leading edge refers to the end of the blade that cuts through water, and the opposite side is referred to as the trailing edge.
A spline, while technically, is not a part of the propeller, refers to the drive shafts teeth. Hubs are designed in a way that allows them to fit shafts with given numbers of splines.
The features of a boat prop: Boat props are classified by their diameter and pitch, and this is often displayed as 2 numbers (in inches), such as 15.5 X 12. One can usually find this stamped on the props hub. The 1st number refers to the props diameter (which would be double the distance from the blades end to the hubs center). The 2nd number refers to the props pitch. The pitch refers to the distance that the propeller can theoretically travel through with every revolution. A prop with a 12 inch pitch could travel around 1 foot with a single revolution. Pitch is often looked upon as a theoretical figure because a prop pitch can experience slips in varied real world scenarios. A slip refers to the difference in ratio between the actual distance that is traveled and the props given pitch. This slip can be varied under similar conditions, an example being that an efficiently planned boat could experience only a 10 percent slip, where as a heavy work boat could experience as much as 80 percent slip.
Rotation of a propeller can be right or left hand, and most boat propellers come with right hand rotation. Left handed rotation is generally found aboard boats that require heavy steering wherein the motors torque is countered using double engines.
A cupped blade refers to the special treatment wherein the prop blades trailing edge is curved. This helps increase performance levels under specific conditions.
The rake refers to the blades angle from the hub. A negative rake indication shows that the blades are pointed forward (towards the boats front), and this is generally done to strengthen high end props.
Before you start, it is important that you note down your engines specifications, such as make, horse power (HP), model, etc. and your existing props details like its material (steel, aluminum, etc), diameter, pitch, and number of blades. You can then comfortably embark upon your hunt for a new boat prop.
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