Understanding the meaning of “burr” to understand the question “what is deburring”. If you work with machined parts, you’ve probably seen burrs on parts at some point. Burrs can make what you make less accurate and have a less smooth surface. For this reason, deburring is an important part of machining.
But despite the importance of deburring parts, most manufacturers don’t know how to do it properly. We have better deburring methods that you can find here. In addition, you’ll learn what burrs are and how they can cause machining problems.
What is a Burr?
Burrs are small, sharp defects on the surface of machined parts. We can call them “impurities” because they spoil the smooth aesthetics of the finished surface.
During the manufacturing process, metal parts go through many steps. These include milling and stamping. These steps are used to make the machined part into the desired shape. However, they are not always perfect. As a result of these defects, small ridges or protrusions of metal can appear on the surface of the finished product. We call these small bumps “burrs.”
Imagine working hard to create a part only to find small bumps on a smooth surface. What would the machined part look like? It probably wouldn’t be pretty. That’s what burrs do to the exterior of a metal part. It makes the part less smooth and may even be harmful to the part.
Types of Burrs
There are three main ways in which burrs can form during machining:
- Flip Burr: A small curved metal protrusion sticking out from the surface of the machined part. This is one of the most common types of burrs.
- Breakout Burrs: Small pieces that appear to be detaching from the machined part during the cutting process. They have an upturned shape, making them look like they are about to break off.
- Poison Burrs: Tiny fragments at the end of a machined part that extend outward to the sides. This is the third type of burr that occurs during machining.
By understanding these factors and types of burrs, manufacturers can take steps to minimize or eliminate burr formation, ensuring higher-quality finished parts.
Why Deburring Is So Important?
Deburring is the process of removing burrs from metal parts to smooth edges and surfaces. It is an important part of the manufacturing process because it makes parts more perfect. Removing these sharp burrs will improve the overall performance and function of the metal parts and ensure a good surface finish.
From an aesthetic point of view, deburring is also an important part of making the product look better. Smooth surfaces and edges enhance the overall appearance of the product, thereby attracting more customers and users. Deburring also eliminates potential safety hazards. Because workers and end users do not have to worry about being cut or injured by sharp edges.
Why Do Burrs Occur During Machining?
Burrs can be created during different machining processes. However, on polished parts, burrs can be minimized or even eliminated.On polished parts, burrs can be stopped or kept to a minimum. Burrs can form during machining or cutting processes. To help you understand how burrs are formed during machining, we have categorized the causes of burr formation into two groups.
The machining processes that may leave burrs on metal surfaces are:
- Drilling
- Engraving
- Milling
- Turning
Cutting processes that may leave burrs on metal surfaces are:
- Blanking
- Punching
- Laser cutting
- Plasma Cutting
- Shearing
After a part has undergone these processes, the surface of the finished part may have burrs. Additionally, other factors can also contribute to burr formation. These factors include:
Operator Proficiency: When the machine operator is skilled and the machine is set up correctly, the likelihood of burr formation is significantly reduced. Conversely, if the part is machined by an unskilled operator, there may be more burrs than expected. This highlights that burr formation is not only influenced by the method but also by the operator’s expertise.
Thickness and Grade of Material: Using high-quality material that is easy to cut can reduce or even eliminate the need for post-processing. This is because such materials are easier to work with and leave little to no burr.
How Do I Remove Burrs?
There are many different ways you can remove burrs and smooth the surface of a metal part. Here are a few ways to remove metal burrs:
Manual Deburring
The manual deburring method can be used for small parts that need to be smoothed. This method is less expensive but time-consuming. Hand deburring does not require large machines. All you need are some basic tools such as sandpaper, files, deburring knives, and other finishing tools.
However, you need to be proficient with these tools to avoid causing more damage to the part. Deburring has always been done this way, and it can be difficult. If one or more large parts are to be deburred, it may not be possible or even possible to do it by hand.
Grinding and Rolling
For this method of deburring, you need a machine. Grinding and tumbling are mechanical methods for removing burrs and obtaining a high-quality finish with ease. It works similar to manual deburring but is faster and more cost-effective.
Electrochemical Deburring
Using other fuzzy methods, it may be difficult or impossible to deburr small metal parts. This is where electrolytic deburring comes in. This method can be used if there is a burr in an area that seems to be out of reach of other deburring methods.
For electrochemical deburring, you need an electrode that is the same shape as the edge you want to smooth. It uses an electric current and chemicals to remove the burr, just like its name suggests. Electrolytic deburring requires an electrolyte and an electric current. There are two types of sodium salt: sodium chloride (table salt) and sodium nitrate. With a solution and an electric current, the burr is successfully removed. This method allows for quick and accurate treatment of difficult areas.
Removing Burrs from Holes
Seeing the name of this method, you probably already know what it is used for. Removing burrs from holes is a different method than removing burrs from flat surfaces. Different tools can be used to deburr the inside of the hole and the process is simple.
You need to spring the cutting tool and place it on the spindle to deburr the hole. You need to place the tool in the right position so that it can easily go through the hole and grind the burr without scratching or damaging the part. Check if the cutting tool has a tapered end. If it does, use it to make a chamfer at the front of the hole. This will allow for faster and better deburring. This method of deburring is both faster and less expensive.
Thermal Deburring
Thermal deburring uses combustible gases to generate heat, which is then used to heat the metal and burn off the burrs. This method is suitable for removing burrs in hard-to-reach places, such as cracks or crevices. It can also deburr multiple areas at the same time.
Electrolytic Deburring
Electrolytic deburring involves using an electric current to convert metal into ions and then remove only the surface imperfections of the workpiece. This method requires particular care. The electrolyte is corrosive and can damage the area around the burr.
Vibratory Polishing
Vibratory polishing is a gentler method of deburring metal parts. It is suitable for processing softer metal parts. The parts are placed in a vibrating or rotating bowl or bucket together with a mixture of liquid and abrasive. As the machine rotates, this polishing medium continuously rubs the parts, removing imperfections such as burrs and sharp edges.
Using Brushing
As you know, brushing is removing burrs with a brush, but not with a regular brush. It requires a type of brush made of a rough material. The idea of this method is the same as that of the manual method using sandpaper and other related tools.
However, unlike the manual method, you can use a machine tool with specialized brushes for brushing. This technology makes these jobs easier and faster. Brushing is a fast and inexpensive way to deburr both simple and complex workpieces.
What Types of Abrasives Are Used in Deburring Machines?
Most deburring tools have abrasives on them. They remove burrs and smooth the surface of the metal being cut. Different types of metal have different grit sizes and materials. However, the following are the most commonly used abrasives:
- Aluminum Oxide: Aluminum oxide is the industry standard in many areas. There are two common types of aluminum oxide: closed-coat and open-coat. Closed-coat is ideal for cutting metal and removing weld seams. Open-coat is better suited for woodworking. The particles of these abrasives are very fragile, which means they break up during use. This ensures that the cutting surface remains sharp at all times.
- Silicon Carbidel:This special abrasive cuts steadily and evenly and is ideal for finishing. Silicon carbide is more expensive than aluminum oxide, but it is more consistent and can even remove burrs without generating heat. It is therefore ideal for heat-sensitive applications.
- Ceramic: Ceramic is a high-quality grit because it is very hard and sharp. It has the longest service life of all the coarse materials. It cuts metal and other hard materials quickly and cleanly without becoming blunt.
- Zircon: Zirconium oxide can be used to grind and clean metal and to remove the edges of hardwood. Before the invention of ceramics, zirconium oxide was the strongest and most durable abrasive grain.
Tips on Design and Cost Savings
There are a number of things you may want to consider when making machined parts. These things will help you save time and money. The following are cost-saving tips:
- Minimizing or Preventing Burrs: Yes, you can make your metal parts burr-free or make burrs less noticeable. To do this, you need to learn how to use your machine properly and set it up correctly. When grinding, you should try to avoid or minimize burrs. This is very important when machining expensive or hard items.
- Remove Burrs Only When Necessary: You do not always need to remove burrs from the finished product. For example, you may not need to remove burrs from a part that is going to another machine shop for further processing. There may be more burrs in the next step of the process.
- Cheaper to Apply with an Abrasive Brush: Using abrasive brushes saves time and money by allowing multiple edges to be deburred at the same time. In addition, brushes last longer, so you don’t have to keep buying new deburring tools.
Conclusion
Choosing the right deburring method is essential for saving time, money, and preventing damage to your workpiece. When done correctly, deburring ensures your machined parts have a smooth, flawless finish. However, knowing when deburring isn’t necessary can also help conserve resources.
Yonglihao Machinery is your go-to rapid prototyping company for machining and fabrication. We guarantee burr-free, professionally finished products tailored to your needs. Whether it’s a prototype you need in a day or durable parts for long-term use, we’ve got you covered. Simply send us your design file, and we’ll provide a quote within 24 hours, along with free artwork reviews for production. With Yonglihao Machinery, you can count on expert service without the need to be on-site.
Further Reading:Metal Surface Finishes Guide
FAQ
What is a burr?
A burr is a small, sharp defect on the surface of machined parts. These defects are typically created during processes such as drilling, milling, and cutting.
Why do burrs occur during machining?
Burrs are caused by many factors. These include the operator’s skill, the material’s thickness and grade, and the machining methods used. Common machining steps like drilling, engraving, milling, and turning can all produce burrs.
How do I remove burrs from machined parts?
There are many ways to remove burrs. These include manual deburring, grinding, and tumbling. There is also electrochemical deburring, deburring holes, and brushing. The best method depends on the specific part and the location of the burrs.
What are the pros and cons of manual deburring?
Manual deburring is suitable for small parts and does not require large equipment, making it less expensive. However, it is time-consuming and requires skilled operation to avoid further damage to the parts.
What is electrochemical deburring?
Electrochemical deburring uses electric current and chemicals. They remove burrs, especially ones in hard-to-reach areas. This method is fast and precise, making it ideal for complex parts.
