Cutting speed vs Feed rate – difference in CNC Turning

 

RCGT Insert

As a raw material, tungsten carbide is a limited natural resource. It is also a widely popular tool material due to its hardness and heat resistance, making machine shops the top consumer of this precious commodity. We can both save money by reducing the consumption of carbide and do our environment a lot of good by fully utilizing every tool before recycling the rest. 

In a recent IMTS Spark webinar, BIG KAISER Vice President Jack Burley offers a sustainable approach to choosing tooling systems. He explains how high-precision tooling systems, which may cost a bit more up front, show a clear return on investment by substantially reducing the use and waste of carbide.

“The quality of your tool holders – collet chucks, hydraulic chucks, milling chucks – matters when it comes to how you hold solid tools like drills, end Milling inserts mills or reamers,” Burley says. “And when you are considering different types or brands of tool holders, there is one important rule to remember: ‘one-tenth equals 10 percent.'” 

This means that for every 0.0001" decrease achieved in runout, there is corresponding 10 percent increase and savings in tool life. In other words, reducing runout with higher quality tool holders reduces carbide consumption. 

“Most manufacturers think that average runout is about 0.0005" and they settle for that along with the corresponding shorter tool life. That is still leaving a lot of your expensive carbide drill unused,” he says. “By using a higher quality tool holder and really minimizing runout, you can easily achieve savings of 30 percent or more on every single tool.”   

By focusing on operational efficiency and total ROI over short-term cost cutting, the business case for quality over cost becomes clear. Watch now for the full story and learn how one precision manufacturer in Missouri promoted teamwork and sustainable manufacturing processes to reduce their tooling costs by 20 to 25 percent.   

Waterjet Cutting Process： How it Works and its Benefits

September 30, 2023

CNC tooling comprises various motorized machines and tools that use pre-programmed software to automate and control different machining operations. These machines play a pivotal role in manufacturing industries. Categorically, the milling fly cutter used in CNC milling operations impacts the finishing of large and flat surfaces. Here, we will take a detailed look at the types, specifications, and applications of fly cutters.

Fly Cutter – Definition

Fly cutters are rotary cutting tools used in sideways motions to machine and produce finished plane surfaces. While these handy tools can be applied to various machines, they are mostly used on CNC milling machines.

For example, fly cutters use one or more single-point tools, also called fly cutter bits, which get inserted into the cylindrical body. Fly cutters get mounted in a special angled holder, so when the whole unit is rotating, these bits take the surfacing cuts for soft materials like aluminum and hard materials like steel.

Moreover, some specific milling fly cutter types, such as the rotary cutting tool, are suitable for cutting, drilling, sanding, carving, and grinding operations. But note that fly cutters apply for mild cutting operations rather than heavy-duty cutting.

Types of Fly Cutters

Most fly cutters get designed and fabricated to meet industrial specifications. Nonetheless, the various types of fly cutters differ in vital considerations such as the cutting material, feed rate and cutting speed. Therefore, depending on your machining project, you must choose the right milling cutter types for finishing large and plane surfaces. Let’s take a closer look at the common types of fly cutters.

1. Point Cutter

As the name suggests, this fly cutter comprises needle-like points designed for cutting heavily populated corals. Most point cutters have two cutting edges per blade, and these ground edges help obtain precise cuts when milling. In addition, point cutters extend to areas that are hard to reach, slipping in and out of the handle for safe storage. Depending on your project, you can opt for either a long (500mm) or short (300mm) blade.

2. Rotary Cutting Tool

This fly cutter applies to cutting, drilling, and grinding various fabrics quickly without altering the patterned cutting line. Sometimes, experts use the rotary cutting tool to cut up to eight layers of fabric in just one milling session.

3. Rotary Carving Tool

Rotary carving tools are usually used for carving operations on hard materials. More specifically, manufacturers apply this fly cutter type to carve through the grain wood or engrave the blown glass.

Fly Cutter Components and Specifications

Fly cutters have unique features and specifications. Check them below:

Components of Fly Cutter

Typical fly cutters come whole comprising a couple of parts which are:

Cylindrical bodyHolderThrust washerFastenersDraw boltA left-handed carbide cutting tool

In most cases, the centrally placed cylindrical body of the milling fly cutter holds one tool bit. Meanwhile, fly cutters with two tool bits are often fastened with one tool bit on each end. Before use, these fly cutter bits get affixed in a special angled holder at the right angle (90 degrees) to the main axis of the bar stock. Also, the left-handed carbide tool is usually held at 30 to 60 degrees.

Specifications and Size of Fly Cutter

There are different ways fly cutters operate. Depending on the type of your milling project, you must ensure each fly cutter bit receives enough power from your milling machine. For instance, the rotary cutting tool comprises a variable speed motor for low to heavy cutting operations with power ranging from 0 to 30000rpm.

Moving forward, note that each length of the fly cutter body uses a specific length of a tool bit for optimal results. For instance, the main body of a rotary cutting tool has a spindle lock, permitting the opening and closing of the 1/8-inch collet to fit standard rotatory purposes. Below are some other vital rules of thumb to keep in mind:

The 3/4-inch body fly cutter uses a 3/16-inch tool bit.The 1-1/8-inch body uses a 1/4-inch tool bit.The 1-3/8-inch body fly cutter uses a 5/16-inch tool bit.

Fly Cutter vs. Face Mill: What are the Differences?

Generally, face milling encompasses the processes of milling flat or plane surfaces positioned at the right angle to the axis of the cutter’s rotatory movement for a quality surface finish. Face mills and TNMG Insert fly cutters differ in certain aspects. Here are some of the differences:

1. Number of Inserts

Fly cutters utilize one or two inserts at a lesser cutting speed to remove excess workpieces during milling operations. In comparison, face mills employ multiple inserts at a higher cutting speed, making them more suitable for heavy material removal. However, the height of face mill inserts cannot be separately adjusted, thus resulting in varying chip loads between the different inserts.

2. Finishing Quality

Face mills operations offer quality surface finishes. In the meantime, milling fly cutters use skim cut techniques lesser to provide a much finer finish. Even so, getting a large face mill remains the better choice for high-volume projects, as they provide faster speed per operation.

3. tungsten carbide inserts Cutting Requirements

The cutting edge of correctly positioned fly cutters can overlay large surfaces in one milling session to produce a very flat surface. On the other hand, face mills have a cutting edge of varying heights, making them more suitable for producing ridged surfaces.

4. Cost

Face mills need more weighty, rigid, and powerful machines with large spindle power, making them expensive. In contrast, milling fly cutters are well-suited for smaller machines with lesser spindle powder and are much cheaper. In addition, the higher the inserts needed, the more the operating costs. Hence, fly cutters are inexpensive compared to face mills, requiring one or two inserts.

Considerations of Fly Cutter for Finishing Surfaces

Fly cutter tools have become indispensable tools for finishing surfaces. However, there are some specific factors to consider before using these tools. Check these considerations below:

Fly Cutter Maintenance

If you are operating a small or light-duty mill, you should use single-toothed fly cutters to get the best performance. On the flip side, multi-toothed milling fly cutters do not work optimally with smaller machines due to the lack of substantial power and rigidity required to drive each tooth through workpieces.

It also remains essential that the fly cutter bit is sharp enough to drive cuts without additional power to overcome challenges and ensure optimal finishing results. Notwithstanding, you can re-sharpen the tool by grinding it straightforwardly after long-term usage.

Point Radius

Professional machinists maintain the point radius of the fly cutter tool to less than 1.5mm. This is because the smaller the point radius, the slower the feed rate, thus giving a fine finish. Thus, make you avoid large tip radiuses as they increase the tool cutting pressure, causing deflections. This eventually results in squealing, chatters, and poor finishing outcomes.

Type of Workpiece

When applying fly cutter to steel grades like 1018, it is best to use carbide bits with zero rakes and at about 5 degrees relief on the surface. However, for aluminum materials such as 6061-TS, experts use high-speed fly cutter bits to grind about 60 degrees of rake on the surface from the end.

Furthermore, most machinists tend to adjust the diameter of normal fly cutters up to 51 mm. Thus, at this set diameter, you can easily apply the fly cutter to take a 0.25 mm deep cut in aluminum.

Applications of Fly Cutters

Fly cutters apply in many manufacturing industries today. In these industries, these mechanical tools are usually operated in CNC tools and manual mills without needing additional arbors. As such, milling fly cutters are often employed to remove a large number of excess workpiece materials and then level it. Most manufacturers apply fly cutters to many materials, including metals, wood, and glass.

WayKen Helps you Choose the Right Cutter for Milling Projects

There are different types of milling fly cutters, and each type has its pros, compatibilities, and limitations that you must cautiously examine. Of course, you also consult an expert to get professional advice.

At WayKen, we specialize in milling services that create high-tolerance precision metal and plastic parts. With years of machining experiences, our engineers can help you quickyly choose the right cutter for the milled parts. What’ more, our in-house machine shop with advanced multi-axis CNC milling machines can help you deliver these parts quickly and affordably. Contact us today to get a free quote and DfM feedback.

Conclusion

Today, CNC milling apply across several manufacturing industries to provide a high level of precision and accuracy, efficiency, and consistency in machining operations. Fly cutters are essential rotary cutting tools with one or more bits inserted into their body. These tools are primarily used on CNC milling machines for machining and leveling large and flat surfaces, like the face mills. This article will guide you in selecting the right fly cutter for your milling project.

FAQ

How do I choose a milling tool?

You must consider vital factors such as the type of material, the dimension of internal and external profiles (Fillet Vs Chamfer ), and the type of desired surface finish for the part.

Why is down milling generally avoided?

Down milling procedures make it harder to trap the chips between the tool and the workpiece. Besides, the rotary movement of milling fly cutters easily throws the chip away.

Can you cut a hole with a fly cutter?

Yes, you can cut a hole with a fly cutter. You can adjust the diameter of the rotary fly cutter to meet the desired dimension of the hole before placing it in the CNC milling machine for drilling.

Drilling tool industry’s requirements and expectations for mining cemented carbide

For those who dabble in manufacturing or prototyping, terms “jig” and “fixture” appear frequently, especially when talking about machining — a subtractive manufacturing process for plastic and metal parts. But what are jigs and Machining Inserts fixtures, what are jigs and fixtures used for, and why are jigs and fixtures so important?

Although often grouped together, these two tools play different functions in the manufacturing process and are often used with different pieces of manufacturing equipment. They both help to produce more accurate and repeatable parts, and both can be made using a few different manufacturing techniques, but jigs and fixtures remain fundamentally different.

This article will serve as an introduction for anyone who needs jigs and fixtures explained. It will look at the main differences between jigs and fixtures, as well as their main applications and how they can be made.

What are jigs and fixtures?

Before getting into the specific attributes of jigs and fixtures, we should Threading Inserts take a step back and ask the broader question of what type of object jigs and fixtures are.

We can think of both of these items as tools or pieces of tooling: implements used in the fabrication of new parts that are distinct from the manufacturing machinery (e.g. CNC machine, 3D printer) and the parts being made. (Other examples of tooling include material forming devices like molds and dies, and cutting tools such as drill bits.)

More specifically, both jigs and fixtures — but especially fixtures — can be considered workholding devices: items used to keep a workpiece (the in-progress part being made) stable and secure during manufacturing.

What is a jig?

We’ll start our explanation of jigs and fixtures with jigs. In short, a jig is a tool used to control or guide the movement of a cutting tool such as a drill (and sometimes to simultaneously hold the workpiece).

So why do manufacturers use jigs? By introducing a tool that precisely guides the movement of a cutting tool, a manufacturer can, for example, guarantee repeatability: ensuring the same cut is made in exactly the same place on several duplicates of a part. The same jig can be used over and over, resulting in the same outcome with each use.

Since their purpose is primarily to guide and direct cutting tools, jigs are most commonly used for manual work, i.e. manual machining and drilling. (CNC machines are less dependent on jigs, since they are designed to provide micron-level precision without assistance; their cutting tools are “guided” by computer instructions.)

Types of jig:

• Template jig: A simple jig that can be fitted onto the workpiece, it has holes through which a cutting tool (e.g. drill) can be guided.
• Plate jig: Similar to a template jig but with drill bushes instead of just holes.
• Angle-plate jig: Used to prop up the workpiece at an angle to facilitate the drilling of e.g. diagonal holes.
• Leaf jig: A jig with a hinged leaf that can be swung open and closed for faster loading or unloading.
• Diameter jig: Used to enable the drilling of rounded workpieces that cannot easily be secured in other types of jig.

What is a fixture?

Fixtures have a few features in common with jigs, but their purpose is essentially different. The sole function of a fixture is to keep a workpiece stable and secure during manufacturing; a fixture is therefore a workholding device in the truest sense.

Fixtures can perform several functions. By keeping a workpiece fully secure, they ensure accuracy and repeatability. They can also be adjusted to hold a workpiece at a specific angle, allowing for cutting operations in a range of directions. Fixtures also minimize errors and guarantee the safety of workers by preventing the workpiece from being accidentally flung from the work table. Like jigs, fixtures are often used in machining operations.

You are likely to see fixtures in use on CNC machining centers and other automated manufacturing equipment. CNC machines can direct their cutting tools without the use of jigs, but they will not work properly if the workpiece cannot be kept secure.

While jigs are typically held in place with fasteners or even held manually by the machine operator, fixtures have a variety of clamping options, including hydraulic, pneumatic, and vacuum systems for applying the requisite force.

Types of fixture:

• Turning fixture: Typically mounted on the machine spindle or a face plate, turning fixtures are useful for more complex lathe-made parts.
• Milling fixture: Typically secured to the work table with fasteners, these fixtures enable a variety of milling operations.
• Drilling fixture: Comprising hole and bushing, drilling fixtures are sometimes used in place of (or in addition to) jigs.
• Grinding fixture: Used to support a workpiece during grinding operations.

The difference between jigs and fixtures

Are jigs and fixtures the same thing? No, they are not: although both are types of tooling used in manufacturing, and although they share some of the same traits, they are distinct objects.

The main difference between a jig and a fixture is that a jig plays some role in controlling the position or movement of another tool, generally a cutting tool, while a fixture is concerned with the position of the workpiece (the piece of material being turned into a new part).

A jig sometimes performs two roles, controlling the position of both the workpiece and another tool, while a fixture performs one.

In practice, this means that jigs and fixtures are often used in different situations. Applications of jigs are often found in manual work, where humans need help to move a cutting tool to the exact point required (to ensure that a drill makes a hole in exactly the right spot, for example). On the other hand, applications of fixtures are found in both manual and automated work: cutting tools do not always need guidance, but a workpiece always needs to be secured to ensure precision and safety.

Other differences between jigs and fixture include:

• Jigs are often fairly lightweight, while fixtures must be heavy enough to provide stability
• Jigs can be held in place manually, while fixtures are mechanically secured to the table
• Jigs may require more intricate design, while fixtures are typically more straightforward

Advantages of jigs and fixtures

The use of jigs and fixtures during manufacturing can lead to significant benefits in terms of production and part quality. The main benefits include:

• Increased production rate
• Eliminates need for manual measurement and alignment
• Consistency and accuracy across multiple parts
• Reduced dependence on manual skill of machinist
• Reduced dependence on post-manufacturing quality control measures
• Improved safety for workers
• Allows machinist to adjust feeds and speeds for faster production

Components of jigs and fixtures

Jigs and fixtures may look like simple tools, but they are typically made up of several sections. These sections are:

Body: The bulk of a jig or fixture is its body, typically a solid piece of metal strong enough to withstand significant forces.

Clamping devices: The clamping devices of a jig or fixture are used to hold a workpiece secure and resist cutting forces.

Locating devices: Typically made from hardened steel, locating devices such as pins are used to put the jig or fixture in the right place.

Bushings: Typically made of tool steel, bushings are used in some jigs to guide the machine tool in its operation.

How to make jigs and fixtures

There are a few different options when it comes to manufacturing jigs and fixtures. While CNC machining has been the dominant method for some time, 3D printing is now a viable alternative.

Although jig and fixture materials are typically metal — more specifically steels such carbon steels, mild steels, and die steels — it is also viable to make plastic jigs and fixtures if low clamping forces are required. Nylon is a common plastic used in jig and fixture production.

Design considerations

• Jigs and fixtures should be foolproof to prevent misplacement
• Cost of production should be less than predicted cost savings
• Location points should be clear (and ideally adjustable) to minimize idle time
• Clamping arrangements should not be complicated
• Jigs and fixtures should be robust enough for use but lightweight enough for easy handling
• Tools should have ample clearance
• There must be adequate space for chip clearance

CNC machining jigs and fixtures

Best for: Robust steel jigs and fixtures, simple geometries

At present, CNC machining is the dominant method for making jigs and fixtures. This is because CNC machining is cost-efficient for small quantities (and jigs and fixtures tend to be custom built for specific parts).

CNC machined jigs and fixtures are ideal when the jigs and fixtures need to be robust but not especially complex in terms of their geometry. Most steel jigs and fixtures are CNC machined.

3D printing jigs and fixtures

Best for: Rapid and plastic jigs and fixtures, complex geometries

3D printing or additive manufacturing is an alternative to CNC machining for rapidly making jigs and fixtures. Like CNC machines, 3D printers are efficient at fabricating one-off items.

3D printed jigs and fixtures can have more complex geometries than machined ones, and 3D printing may be a more affordable option for plastic jigs and fixtures (via SLS, for example). In most cases, however, machined jigs and fixtures have superior strength.