How a Wood Chipper Works: A Step-by-Step Breakdown

Wood chippers are essential tools in forestry, landscaping, and property maintenance. They efficiently convert bulky tree branches and woody debris into manageable wood chips.

This article will give you a comprehensive understanding of how a wood chipper works, exploring its components, operational process, and various applications.

If you're considering purchasing a wood chipper, this step-by-step breakdown will give you a clear understanding of how useful they can be.

What is a wood chipper?

A wood chipper is a mechanical device used to reduce wood and branches into smaller wood chips. These machines come in various sizes and types, from a small electric chipper to larger industrial machines, catering to different needs from small garden maintenance to large-scale commercial operations. While there are small wood chippers, there are models across many size ranges with different levels of capacity.

Types of wood chippers include:

Commercial wood chippers: These are heavy-duty machines designed for continuous, high-volume use in professional settings. They are typically powered by a large internal combustion engine, and can produce a higher output of wood chips, but a commercial wood chipper can be expensive, bulky and outweigh the needs of the average acreage owner.

PTO-powered wood chippers: These attach to tractors and use the tractor's power take-off (PTO) system as their power source. Because they can be hauled by a tractor, they are easy to maneuver around country property.

Gas-powered wood chippers: These offer greater mobility than electric wood chippers because they don't require an electrical outlet or a tractor's PTO.

Benefits of using a wood chipper

Wood chippers offer several advantages in various applications:

Environmental Benefits: By converting woody waste into mulch or compost material, wood chippers help reduce landfill waste and promote organic recycling.

Efficiency: Wood chippers can quickly process large volumes of branches and debris, saving significant time and labor compared to manual methods.

Space Saving: Converting bulky branches into compact wood chips dramatically reduces the volume of waste, making storage and transport more manageable.

Versatility: The resulting wood chips have multiple uses in landscaping, gardening, and even as biomass fuel.

Cost-Effective: For properties with regular tree maintenance needs, owning a wood chipper can be more economical than repeatedly hiring removal services or renting equipment.

Five key components of a wood chipper

To understand how a wood chipper functions, it’s essential to familiarize yourself with its main components. While designs may vary between models, most commercial wood chippers share these four key elements:

1. Infeed Chute 

The infeed chute is the entry point of the wood chipper. It’s a funnel-shaped opening designed to guide branches and wood pieces safely into the chipping mechanism. The size and shape of the hopper will vary, depending on the chipper’s capacity and intended use.

2. Infeed System

Each wood chipper is equipped with an infeed system which feeds the material from the infeed chute. Hydraulic infeed uses rollers powered by a self-contained system to pull material into the chipping mechanism. Gravity infeed systems use a sloped chute and often rely on gravity alone to feed material directly into the flywheel.

3. The Chipping Mechanism

This is the heart of the wood chipper, where the actual size reduction occurs. There are two main types of chipping mechanisms, and they both rely on sharp chipper blades and high-speed rotation to effectively chip wood:

Drum Chipper: Uses a rotating drum with cutting blades mounted on its surface. As the drum rotates, it pulls in material and chips it against a stationary anvil. The chipping blades in drum chippers are designed to handle larger, tougher materials efficiently.

Disc Chipper: Features a large, rotating steel disc with chipper blades or cutting blades mounted on its face. As the disc spins at high speed, the blades cut the wood into chips. Different designs of chipping blades in disc chippers enhance their efficiency and safety.

There is also an innovative new type of disc chipper available, the Twin Flywheel chipper. A twin flywheel chipper uses two rotating steel discs instead of one. The first disc cuts the wood into chips, and the second disc, which spins at twice the speed, powerfully throws the chipped material through the discharge chute.

4. The Discharge Chute 

After the wood is chipped, it needs to exit the machine. The discharge chute is a tube that expels the wood chips. Many models allow adjustment of the chute to control the direction and spread of the discharged chips.

5. Engine or Power Source

Wood chippers require substantial power to operate effectively. Power sources can include:

• PTO systems: Used in chippers designed to attach to tractors

• Gas engines: Common in larger, more powerful chippers

• Electric motors: Typically found in smaller, residential-use chippers, offering benefits such as lower maintenance and cleaner operation compared to gas engines

How a wood chipper works: Step-by-step

Understanding the step-by-step process of how this machine works can help users operate these machines more effectively and safely. Let's break down the operation into four main steps:

1. Feeding the infeed chute

The process begins with feeding material into the infeed chute. It's crucial to consider the size and type of material being fed:

• Ensure your wood chipper's capacity is in line with the material you want to feed it

• Avoid feeding painted or treated wood, as well as materials containing metal or stones

Proper feeding technique involves:

• Inserting the thicker end of branches first

• Allowing the chipper to pull the material in rather than forcing it

2. Material is pulled into the chipper

Once material enters the hopper, it's drawn into the chipping mechanism. In some machines this is facilitated by feed rollers:

• Feed rollers grip the material and control its entry into the cutting area

• The speed of these rollers can often be adjusted to optimize chipping performance for different materials

The chipper blades in action

This is where the actual chipping occurs:

• In a disc chipper, the material contacts the rapidly spinning disc

• Sharp blades mounted on the disc slice through the wood

• Centrifugal force plays a crucial role, helping to expel the chips once they're cut

• In Twin Flywheel chippers, the second flywheel expels the chips faster and further

In drum chippers:

• The rotating drum pulls material in

• Blades on the drum's surface cut against a stationary anvil

• The drum's rotation creates the necessary force to chip and expel the material

 4. The wood chips are discharged

 After chipping, the wood chips exit the machine through the discharge chute:

•  The high-speed rotation of the cutting mechanism propels the chips out

• Many chippers allow adjustment of the discharge chute to direct where the chips land

 The discharged wood chips can be:

•  Spread directly as mulch

• Collected for later use in landscaping or gardening

• Gathered for composting or as biomass fuel

Safety precautions when using a wood chipper

While wood chippers are invaluable tools, they require careful operation to ensure safety:

•  Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, gloves, and close-fitting clothing

•  Proper Training: Ensure all operators are thoroughly trained in the machine's use and safety features

•  Maintain a Safe Distance: Keep hands and feet away from the hopper when the machine is running

•  Use Push Sticks: For feeding smaller materials, use a wooden push stick rather than your hands

•  Avoid Loose Clothing: Never wear loose-fitting clothes or jewelry that could get caught in the machine

•  Regular Maintenance: Keep blades sharp and perform regular maintenance to ensure safe, efficient operation

•  Be Aware of Surroundings: Ensure the area around the chipper is clear of people, animals and obstacles

Choosing the Right Wood Chipper

Choosing the right wood chipper can be a daunting task, especially for those new to the world of wood chipping. With so many options available, it’s essential to consider several factors before making a purchase. Here are some key considerations to keep in mind:

• Pick a wood chipper that has the right capacity you need to chip the material on your property

• Decide whether you will use PTO power or gas to power your wood chipper

• Look at what types of brush and garden debris you plan on chipping

• Examine whether your chipping material will be dry branches or more wet leafy material

More FAQs

What is the difference between a wood chipper and a wood shredder?

While often used interchangeably, wood chippers and shredders have distinct differences:

Wood chippers use sharp blades to cut wood into uniform chips. Meanwhile wood shredders use blunt blades or flails to break down leafy or fibrous material into smaller, less uniform pieces.

Many machines combine both functions and are called chipper shredders.

Are wood chippers worth it?

For properties with many trees or regular landscaping needs, a wood chipper can save time, effort, and disposal costs. They also provide a way to recycle wood waste into useful mulch or compost material.

What are whole tree chippers?

Whole tree chippers are large wood processing machines designed to handle substantial material diameters, typically between 60 to 180 cm. These machines can process entire trees and use advanced technology, such as drums or disks, to transform wood into chips or shredded material.

Wood chippers are great property management tools

Understanding how a chipper works will help you operate these machines more effectively and safely. Whether you're managing an acre of land or a large commercial property, choosing the right wood chipper can significantly streamline your wood waste management process.

Make your wood chipper work for you, to get the job done, wherever you need on your property.