How big of a log can you put in a chipper?
The size of log a wood chipper can handle is a critical question for anyone looking to process woody debris. Not all chippers are built the same, and understanding their limits is key to safe and efficient operation.
The size of a log you can put into a chipper depends entirely on the specific model and its design, primarily limited by the infeed opening's dimensions and the machine's engine power . While small chippers handle branches, industrial models can process logs from 12 inches (300mm) up to 16 inches (400mm) in diameter, and specialized horizontal grinders can even take up to 1.5 meters (5 feet) .
In my 22 years in manufacturing wood chippers, I've seen firsthand the importance of matching the material to the machine . Trying to force a log too large for a chipper can lead to serious problems like machine damage or even injury .
Our customers, from forestry companies to waste management centers, deal with all sorts of woody material, and our machines are designed to meet those varied needs . Let’s explore what determines "how big" a log a chipper can truly handle.
What is the maximum diameter for a wood chipper?
When you're looking at a pile of logs or branches, the most immediate question is often, "Will it fit?" The maximum diameter a chipper can take is a fundamental specification that tells you just that.
The maximum diameter a wood chipper can handle is determined by its infeed opening size and the power of its engine, with models ranging from garden chippers processing small branches to industrial machines capable of chipping logs up to 16 inches (400mm) in diameter, and even larger for specialized equipment .
Limits by Chipper Category
The range of wood chipper sizes means there's a machine for almost every need, from backyard cleanup to large-scale industrial processing.
Garden Chippers: These are typically smaller, more portable units. Our ZSYL-600 model, for example, can handle branches up to 12 cm (approximately 4.7 inches) in diameter . A slightly larger garden chipper, like the ZSYL-800, can process branches up to 15 cm (about 5.9 inches) . These are ideal for homeowners or small businesses dealing with light garden waste and general yard debris .
Mobile Chippers (Medium Duty): Stepping up in size, our ZSYL-1053 model can take branches up to 25 cm (approximately 9.8 inches) . These machines are often road-towable, making them versatile for landscaping and tree care professionals who move between different job sites . They offer a good balance of capacity and mobility.
Industrial Chippers (Heavy Duty): For larger-scale operations, industrial wood chippers are built to handle substantial material. Our larger models can process wood up to 50 cm (about 19.7 inches) in diameter . These are designed for heavy-duty work like large-scale land clearing, biomass production, or processing urban wood waste . For instance, a model like the ZSYL-1585 has a maximum infeed size of 750mm x 700mm . This means it can accommodate very large and even irregularly shaped pieces of wood. Another example is the ZSYL-1263 series, which can handle wood with a maximum diameter of 350mm (14 inches) , or even 430mm (16 inches) .
Horizontal Grinders: For the truly massive jobs, horizontal grinders go beyond what traditional chippers can handle. These machines are designed for high production and can process logs and other woody materials with diameters far exceeding that of typical chippers . Our industrial-grade horizontal grinders are specifically designed to handle logs, with some models capable of processing up to 1.5 meters (approximately 59 inches or 5 feet) in diameter in a single pass . This makes them suitable for agricultural land clearing, post-disaster debris removal, and producing biomass fuel for power plants . For example, the CTZX1400 model of traditional heavy-duty horizontal grinder can take up to 80 cm (about 31.5 inches) logs , while the CTZX1600 can also handle up to 80 cm logs . Some of our horizontal grinders are designed to process waste wood with a maximum diameter of 60 cm (about 23.6 inches) . Another model like the CTQX1000 can process logs up to 50 cm (about 19.7 inches) in diameter .
My experience shows that choosing the right model isn't just about the maximum diameter listed on the spec sheet, but also matching the chipper's capabilities to your specific work density and material type . This includes considering the power and efficiency our machines offer through features like intelligent feeding systems .
Factors Determining Log Size Capacity
The stated maximum diameter is not the only factor. Several other elements work together to define how effectively a chipper processes larger pieces of wood.
Infeed Opening Size and Design: The physical dimensions of the chipper’s mouth are the primary limiter. If a log is too thick to fit into the opening, the chipper simply cannot process it . Beyond just width and height, the design of the infeed system plays a huge role. Our machines feature hydraulic forced feeding systems that are designed to handle different material diameters easily. They adjust the speed to ensure optimal performance and higher output . This means that even with irregular-shaped branches or logs, the material is efficiently pulled into the cutting mechanism . A good log chipper usually has a hydraulic infeed system with rollers that grip the log and pull it into the cutting mechanism at a controlled rate .
Engine Horsepower (HP): A larger diameter log requires significantly more power to chip efficiently. Higher horsepower (HP) engines are necessary to cut through dense log material effectively without stalling . Smaller chippers typically have lower HP (e.g., 10-50 HP) , while larger log chippers require higher HP, often ranging from 50 to over 200 HP . Our industrial chippers can have engines from 235 HP up to 400 HP . We offer top-tier diesel engines, like Cummins, for powerful and reliable operation .
Feeding Mechanism: For logs, a powerful and controlled feeding mechanism is crucial. Gravity-fed chippers are generally only suitable for small branches. For logs, a hydraulic forced feed system is essential . This system provides controlled, powerful feeding of heavy logs, preventing them from jamming the machine . Our chippers are equipped with intelligent feeding systems that monitor the load in real-time. If there's too much material or a blockage starts to occur, the system automatically adjusts the feed speed or stops the feed altogether . This protects the machine from damage and ensures smooth operation .
Chipper Design and Build: Log chippers need to be built with robust, heavy-duty construction to withstand the stress of processing dense material . This includes reinforced steel structures and powerful hydraulic systems for stable operation, even in extreme conditions . Trying to put a large log into a small chipper can cause big problems, like breaking the machine .
It's always important to check the manufacturer's specifications and never exceed the stated maximum diameter . Overloading the chipper can lead to inefficiency, damage, and potential safety hazards .
What size chips does a wood chipper make?
Beyond just fitting the material into the machine, the size of the output chips is a key consideration, as it determines the final use of the processed wood.
Wood chippers can produce a variety of chip sizes, typically ranging from very small, less than 5mm, up to larger chunks of 50mm or more, depending on the chipper model, blade configuration, and specific adjustments . Consistent chip size is often crucial for downstream applications like biomass fuel or mulch .
Adjustability and Output Range
Modern wood chippers offer flexibility in chip size, but the exact range depends on the machine's design and how it can be adjusted.
Adjustable Chip Size: Many chippers allow you to adjust the size of the finished chips to meet your specific needs . This adjustability is often achieved by changing the cutting blade angle, screen size, or setting the clearance between the blades and the anvil . For example, our chippers can produce chip sizes ranging from 5 mm to 50 mm . This means you can get either very fine chips or larger, more coarse ones depending on your application.
Typical Chip Size Distribution: While an average range is given, the output often consists of a distribution of sizes. For instance, some of our models produce chips where:It’s important to note that the hardness and size of the raw wood can affect this data . Harder woods or very large pieces might result in a slightly different distribution.
Approximately 10% are smaller than 5mm .
Around 60% are between 5mm and 20mm .
About 25% are between 20mm and 50mm .
A small percentage (around 5%) might be larger than 50mm .
Specific Applications and Chip Size:
Biomass Fuel: For biomass fuel, chip consistency is very important for efficient burning . Our chippers are widely used to prepare feedstock for biomass power plants .
Mulch: Wood chips are excellent for landscaping mulch, which conserves soil moisture and suppresses weeds .
Animal Bedding: For animal bedding, specific chip sizes are often preferred. Larger shavings are ideal for livestock like cattle and sheep, while smaller shavings are perfect for smaller animals such as hamsters and rabbits .
Construction Boards: Chips can also be used in the manufacturing of construction boards .
Compost: Chips can act as a crucial material for composting, balancing carbon and nitrogen .
The ability to control chip size adds significant value, making the processed wood suitable for a wide array of secondary applications, maximizing resource utilization.
Conclusion
Understanding both the maximum log diameter a chipper can handle and the adjustability of its output chip size is essential for choosing the right machine to meet your processing needs and maximize value.
