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What To Know About Helical Solution’s Zplus Coating

Non-ferrous and non-metallic materials are not usually considered difficult to machine, and therefore, machinists often overlook the use of tool coatings. But while these materials may not present the same machining difficulties as hardened steels and other ferrous materials, a coating can still vastly improve performance in non-ferrous applications. For instance, materials such as aluminum and graphite can cause machinists headaches because of the difficulty they often create from abrasion. To alleviate these issues in non-ferrous machining applications, a popular coating choice is Helical Solution’s Zplus coating.

zplus coating

What is Helical Solutions’ Zplus Coating?

Helical’s Zplus is a Zirconium Nitride-based coating, applied by a Physical Vapor Deposition (PVD) process. This method of coating takes place in a vacuum and forms layers only microns thick onto the properly prepared tool. Zirconium Nitride does not chemically react to a variety of non-ferrous metals, increasing the lubricity of the tool and aiding in chip evacuation.

zplus coating

When Should a Machinist Use Helical Solution’s Zplus?

Working with Abrasive Materials

While Zplus was created initially for working in aluminum, its hardness level and maximum working temperature of 1,110°F enables it to work well in abrasive forms of other non-ferrous materials, as well. This coating decreases the coefficient of friction between the tool and the part, allowing it to move easier through more abrasive materials. This abrasion resistance decreases the rate of tool wear, prolonging tool life.

Concerns with Efficient Chip Evacuation

One of the primary functions of this coating is to increase the smoothness of the flutes of the tool, which allows for more efficient chip removal. By decreasing the amount of friction between the tool and the material, chips will not stick to the tool, helping to prevent chip packing. The increased lubricity and smoothness provided by the coating allows for a higher level of performance from the cutting tool. Zplus is also recommended for use in softer, gummy alloys, as the smooth surface encourages maximum lubricity within the material – this decreases the likelihood of those gummier chips sticking to the tool while machining.

Large Production Runs

Uncoated tools can work well in many forms of non-ferrous applications. However, to get a genuinely cost-effective tool for your job, the proper coating is highly recommended. Large production runs are known for putting a lot of wear and tear on tools due to their increased use, and by utilizing an appropriate coating, there can be a significant improvement in the tools working life.

When is Zplus Coating Not Beneficial to My Application?

Finishing Applications

When your parts finish is vital to its final application, a machinist may want to consider going with an uncoated tool. As with any coating, ZrN will leave a very minor rounded edge on the tip of the cutting edge. The best finish often requires an extremely sharp tool, and an uncoated tool will have a sharper cutting edge than its coated version.

 

What to Know About Harvey Tool’s TiB2 Coating

Aluminum and magnesium alloys are common materials found in machine shops worldwide, and are known as an “easier” material to machine. However, machinists can still experience hiccups while machining this material if they are not prepared with the proper tooling.. When working with aluminum and magnesium alloys, it is important to choose a coating that will work to extend your tool’s life and aid in the removal of chips. A popular choice for this material bucket is Harvey Tool’s TiB2 coating.

What is Harvey Tool’s TiB2 Coating?

Harvey Tool’s TiB2 coating is a Titanium Diboride, ceramic-based coating that provides superb erosion resistance during machining. TiB2 is added to a tool by a method called Physical Vapor Deposition (PVD), which is conducted in a vacuum where particles are vaporized and applied onto a surface, forming thin layers of material onto the properly-prepped tool. This method enables the coating to be corrosion and tarnish resistant.

TiB2 Specifications

TiB2 is identified in Harvey Tool’s product catalog with a “-C8” following the sku number. It can be found offered in Harvey Tool’s lines of Variable Helix End Mills for Aluminum Alloys, Double Angle Shank Cutters, and Miniature High Performance Drills for Aluminum Alloys.

When Should a Machinist Use TiB2?

Chip Evacuation Concerns

TiB2 has an extremely low affinity to aluminum, which helps with the chip evacuation process. Simply, chips of a material are able to evacuate through chip valleys easier if they don’t have a high affinity to the coating being used. TiB2 coating does not chemically react with aluminum and magnesium, which allows for smoother chip evacuation, as the chips do not stick to the coating and create issues such as chip packing. This is a common machining mishap that can cause both part and tool damage, quickly derailing a machining operation. By using a coating that increases the lubricity of the tool, chips will not have a surface to stick to and will more smoothly evacuate from the flutes of the tool.

Large Production Runs

While an uncoated tool may work fine in some applications, not all applications can succeed without a tool coating. When working with large production runs where the tools need to hold up through the process of machining large numbers of parts, using a coating is always recommended because they extend the life of your tool.

When is TiB2 Coating Not Beneficial to My Application?

Extremely Abrasive Materials

During the PVD coating process, tools can reach a temperature in excess of 500° F, which can cause the toughness of the carbide to drop slightly. This process does not normally compromise the performance of the tool due to the coating being placed over the carbide. The coating then protects the slightly weakened edge and increases tool performance in recommended materials. Micro-fractures only start appearing when the tool is being run incredibly fast through highly abrasive materials, leading to a decrease in the life of the tool.

Extremely Soft Materials

The coating, while only a few microns thick at most, still provides an ever-so-slight rounded edge to the cutting edge of the tools it is placed on. It is important to take this into consideration, as using the sharpest tools possible when working with materials such as soft plastics is recommended. The sharpest edge possible decreases the likelihood of any “pushing” that might occur on the material and increases the likelihood of proper “shearing” when machining.

When Finish Is Vital

If your part’s finish is imperative to the final product, an uncoated tool may work better for your application. A coating, like stated above, creates a microscopic rounded surface to the cutting edge of the tool. When running tools at finishing speeds and feeds in materials like aluminum, a sharp edge can create the difference between a finished part that does – or does not – pass final inspection.

5 Questions to Ask Before Selecting an End Mill

Few steps in the machining process are as important as selecting the best tooling option for your job. Complicating the process is the fact that each individual tool has its own unique geometries, each pivotal to the eventual outcome of your part. We recommend asking yourself 5 key questions before beginning the tool selection process. In doing so, you can ensure that you are doing your due diligence in selecting the best tool for your application. Taking the extra time to ensure that you’re selecting the optimal tool will reduce cycle time, increase tool life, and produce a higher quality product.

Question 1: What Material am I Cutting?

Knowing the material you are working with and its properties will help narrow down your end mill selection considerably. Each material has a distinct set of mechanical properties that give it unique characteristics when machining. For instance, plastic materials require a different machining strategy – and different tooling geometries – than steels do. Choosing a tool with geometries tailored towards those unique characteristics will help to improve tool performance and longevity.

Harvey Tool stocks a wide variety of High Performance Miniature End Mills. Its offering includes tooling optimized for hardened steels, exotic alloys, medium alloy steels, free machining steels, aluminum alloys, highly abrasive materials, plastics, and composites. If the tool you’re selecting will only be used in a single material type, opting for a material specific end mill is likely your best bet. These material specific tools provide tailored geometries and coatings best suited to your specific material’s characteristics. But if you’re aiming for machining flexibility across a wide array of materials, Harvey Tool’s miniature end mill section is a great place to start.

Helical Solutions also provides a diverse product offering tailored to specific materials, including Aluminum Alloys & Non-Ferrous Materials; and Steels, High-Temp Alloys, & Titanium. Each section includes a wide variety of flute counts – from 2 flute end mills to Multi-Flute Finishers, and with many different profiles, coating options, and geometries.

Question 2: Which Operations Will I Be Performing?

An application can require one or many operations. Common machining operations include:

  • Traditional Roughing
  • Slotting
  • Finishing
  • Contouring
  • Plunging
  • High Efficiency Milling

By understanding the operations(s) needed for a job, a machinist will have a better understanding of the tooling that will be needed. For instance, if the job includes traditional roughing and slotting, selecting a Helical Solutions Chipbreaker Rougher to hog out a greater deal of material would be a better choice than a Finisher with many flutes.

Question 3: How Many Flutes Do I Need?

One of the most significant considerations when selecting an end mill is determining proper flute count. Both the material and application play an important role in this decision.

Material:

When working in Non-Ferrous Materials, the most common options are the 2 or 3-flute tools. Traditionally, the 2-flute option has been the desired choice because it allows for excellent chip clearance. However, the 3-flute option has proven success in finishing and High Efficiency Milling applications, because the higher flute count will have more contact points with the material.

Ferrous Materials can be machined using anywhere from 3 to 14-flutes, depending on the operation being performed.

Application:

Traditional Roughing: When roughing, a large amount of material must pass through the tool’s flute valleys en route to being evacuated. Because of this, a low number of flutes – and larger flute valleys – are recommend. Tools with 3, 4, or 5 flutes are commonly used for traditional roughing.

Slotting: A 4-flute option is the best choice, as the lower flute count results in larger flute valleys and more efficient chip evacuation.

Finishing: When finishing in a ferrous material, a high flute count is recommended for best results. Finishing End Mills include anywhere from 5-to-14 flutes. The proper tool depends on how much material remains to be removed from a part.

High Efficiency Milling: HEM is a style of roughing that can be very effective and result in significant time savings for machine shops. When machining an HEM toolpath, opt for 5 to 7-flutes.

end mill selection

Question 4: What Specific Tool Dimensions are Needed?

After specifying the material you are working in, the operation(s) that are going to be performed, and the number of flutes required, the next step is making sure that your end mill selection has the correct dimensions for the job. Examples of key considerations include cutter diameter, length of cut, reach, and profile.

Cutter Diameter

The cutter diameter is the dimension that will define the width of a slot, formed by the cutting edges of the tool as it rotates. Selecting a cutter diameter that is the wrong size – either too large or small – can lead to the job not being completed successfully or a final part not being to specifications.  For example, smaller cutter diameters offer more clearance within tight pockets, while larger tools provide increased rigidity in high volume jobs.

Length of Cut & Reach

The length of cut needed for any end mill should be dictated by the longest contact length during an operation. This should be only as long as needed, and no longer. Selecting the shortest tool possible will result in minimized overhang, a more rigid setup, and reduced chatter. As a rule of thumb, if an application calls for cutting at a depth greater than 5x the tool diameter, it may be optimal to explore necked reach options as a substitute to a long length of cut.

Tool Profile

The most common profile styles for end mills are square, corner radius, and ball. The square profile on an end mill has flutes with sharp corners that are squared off at 90°. A corner radius profile replaces the fragile sharp corner with a radius, adding strength and helping to prevent chipping while prolonging tool life. Finally, a ball profile features flutes with no flat bottom, and is rounded off at the end creating a “ball nose” at the tip of the tool. This is the strongest end mill style.  A fully rounded cutting edge has no corner, removing the mostly likely failure point from the tool, contrary to a sharp edge on a square profile end mill. An end mill profile is often chosen by part requirements, such as square corners within a pocket, requiring a square end mill.  When possible, opt for a tool with the largest corner radius allowable by your part requirements. We recommend a corner radii whenever your application allows for it. If square corners are absolutely required, consider roughing with a corner radius tool and finishing with the square profile tool.

Question 5: Should I use a Coated Tool?

When used in the correct application, a coated tool will help to boost performance by providing the following benefits:

  • More Aggressive Running Parameters
  • Prolonged Tool life
  • Improved Chip Evacuation

Harvey Tool and Helical Solutions offer many different coatings, each with their own set of benefits. Coatings for ferrous materials, such as AlTiN Nano or TPlus, typically have a high max working temperature, making them suitable for materials with a low thermal conductivity. Coatings for non-ferrous applications, such as TiB2 or ZPlus, have a low coefficient of friction, allowing for easier machining operations. Other coatings, such as Amorphous Diamond or CVD Diamond Coatings, are best used in abrasive materials because of their high hardness rating.

Ready to Decide on an End Mill

There are many factors that should be considered while looking for the optimal tooling for the job, but asking the aforementioned five key question during the process will help you to make the right decision. As always, The Harvey Performance Company Technical Service Department is always available to provide recommendations and walk you through the tool selection process, if need be.

Harvey Tool Technical Support: 800-645-5609

Helical Solutions Technical Support: 866-543-5422

Helical Solutions: Behind the Scenes

We have shown our end users bits and pieces of our manufacturing process on our website and via social media, but for the first time we decided to open our own doors to the public and show you every step behind how we manufacture and fulfill the Helical Solutions product. We partnered with John Saunders from NYC CNC to create a “Factory Tour” video, covering topics like our CNC grinding machines and setups, tool manufacturing, and our warehouse organization and fulfillment procedures.

In the video below, we first toured our Gorham, Maine manufacturing plan with Plant Manager Adam Martin. Then, we ran a few tests with the Helical tools on our Haas machine, before heading back to our warehouse in Massachusetts to talk about fulfillment and new products with Fulfillment Manager Megan Townsley.

 

 

7 Facts Revealed in Our Factory Tour (Plus 3 More That Didn’t Make the Cut)

We know you’re busy making amazing parts, and might not have time for the entire video. To save you time, here are some of the most important facts you should know about Helical.

We Take Quality Control Seriously

Our high performance end mills go through an extensive inspection and quality assurance process before they end up in your machine, with multiple inspection points along the manufacturing journey. At the 17 minute mark of the video, you can learn more about how we monitor the quality of the tools in batches as they are manufactured. If you skip ahead to the 29 minute mark, you can see some of our more advanced inspection machines in action.

We Stand Behind Our Tools with Our Renewal Services

Our Tool Renewal service is a great way to maximize your cost-savings and avoid having to re-purchase new tools without sacrificing any aspects of the original design. At Helical, we do not re-sharpen tools. Rather, we restore your tools to their original geometry. We will review the condition of your used tools and return the cutting edge to its original sharpness and strength, allowing the tool to retain its outstanding performance. The renewed tools go through the same rigorous inspection, edge prep, and coating process that we follow for all our of our new tools. To learn more about our Tool Renewal services, head to the 23:30 mark in the video.

Our Tool Coating Is Done In-House

We have multiple tool coating machines in-house which allow us to take the ground tools right off the line and transfer them to our coating room to have Aplus, Zplus, or Tplus coatings added. These machines also have the capability to create roughly 20 different coatings, which are reserved for specials and custom orders. If you want a close-up look at the coating room and learn how the PVD coating process actually works, head to the 35 minute mark.

Our Standard Catalog Items Are Stocked and Ready for Your Machine

We don’t make our standard catalog tools to order. All of our standard tools are stocked and ready to make some chips in your machine. We also introduce hundreds of new tools to our annual catalog to keep providing our customers with the latest in high performance tooling technology. You can check out our new tools for 2018, including our new High Balance Tools and Metric Tooling, by heading to 52:20, or take quick look at our rows of stocked tools in our warehouse by jumping to 56:55.

Diamond Wheels Grind Carbide Tools

Diamond grinding wheels are the essential tool (outside of the machine) when it comes to grinding carbide. We have a unique management system for our diamond wheels, and a redressing process which can see these wheels last up to a year or more before they need replacement. Adam goes through our “frozen wheel” room with John at the 32:45 mark in the video above.

We Track Every Batch of Tools With Laser Etching

Our tools are all laser etched on-site with our logo, phone number, and tool description, but also with a specific batch number. These batch numbers allow us full track-ability of every tool so we can quickly asses any questions or concerns a customer may have about a tool. With these numbers, we are able to track the tool’s journey all the way back to which machine it was made on, which grinding wheel was used, and who ran the program. We have a couple of these laser etching machines in Maine, which you can see in action at the 42 minute mark.

If You Can Dream It, We Have Probably Made It

We have had some crazy tool drawings come in to our custom tool program over the years, including oddly shaped form tools, tools with a crazy long length of cut, “paper cutters”, and more. You can see some cool examples of custom tools we have manufactured by jumping to the 20 minute mark. If you are more interested in how we actually make them, head to the 27 minute mark to see one of our large custom tools being ground on our Walter machines.

Our Technical Resources Are Second To None

We don’t leave you hanging after your purchase of Helical tools. We have a multitude of technical resources and How-Tos available here on our blog, and we also offer the HEM Guidebook, a complete guide to High Efficiency Milling techniques.

If you are looking for information on speeds and feeds, we suggest you try our Machining Advisor Pro application. This application is designed to increase metal removal rates and shop productivity by generating customizable running parameters optimized for your Helical Solutions end mills. You can click here to get started with Machining Advisor Pro today.

You Will Always Get a Real Person When You Call Helical

If you have technical questions about an upcoming job, a special application, or tooling selection, you can contact Helical by phone at 866-543-5422. Our technical experts are available over the phone Monday-Friday from 8 AM to 5 PM EST, and you will always get a real person to talk to with no automated systems to navigate through. You can also reach our team by email at [email protected].

Questions about where to buy Helical tools? You can give our team a call, or you can find your local distributor by using the “Find a Distributor” tool on our website. Simply choose your state to see a complete list of authorized distributors in your area.

We’re Hiring!

We have a current list of our open opportunities on our website! Open jobs include CNC Machinist, Quality Control Inspector, and Customer Service Representative.

Shining a Light on Diamond End Mills

Diamond tooling and diamond-coated end mills are a great option when machining highly abrasive materials, as the coating properties help to significantly increase tool life relative to uncoated carbide tools. Diamond tools and diamond-like coated tools are only recommended for non-ferrous applications, including highly abrasive materials ranging from graphite to green ceramics, as they have a tendency to break down in the presence of extreme heat.

Understanding the Properties of Diamond Coatings

To ensure proper diamond tooling selection, it’s critical to understand the unique properties and makeup of the coatings, as there are often several diamond coating variations to choose from. Harvey Tool, for example, stocks Amorphous Diamond, CVD Diamond, and PCD Diamond End Mills for customers looking to achieve significantly greater tool life when working in non-ferrous applications.

Diamond, the hardest known material on earth, obtains its strength from the structure of carbon molecules. Graphite, a relatively brittle material, can have the same chemical formula as diamond, but is a completely different material; while Graphite has a sp2 bonded hexagonal structure, diamond has a sp3 bonded cubic structure. The cubic structure is harder than the hexagonal structure as more single bonds can be formed to interweave the carbon into a stronger network of molecules.

diamond tool coatings

Amorphous Diamond Coating

Amorphous Diamond is transferred onto carbide tools through a process called physical vapor deposition (PVD). This process spreads a mono-layer of DLC coating about 0.5 – 2.5 microns thick onto any given tool by evaporating a source material and allowing it to condense onto that tool over the course of a few hours.

amorphous diamond coating

Chemical Vapor Deposition (CVD)

Chemical Vapor Deposition (CVD) is a coating process used to grow multiple layers of polycrystalline diamond onto carbide tooling. This procedure takes much longer than the standard PVD coating method. During the coating process, hydrogen molecules are dissociated from the carbon molecules deposited onto the tool, leaving a diamond matrix under the right temperature and pressure conditions. Under the wrong conditions, the tool may be simply coated in graphite. 6% cobalt carbide blanks allow for the best adhesion of diamond and a substrate. CVD diamond coated end mills have a typical thickness of coating that is between 8 and 10 microns thick.

CVD Diamond Coating

Polycrystalline Diamond (PCD)

Polycrystalline Diamond (PCD) is a synthetic diamond, meaning it is grown in a lab and contains mostly cubic structures. Diamond hardness ranges from about 80 GPa up to about 98 GPa. PCD end mills have the same diamond structure as CVD diamond tools but the binding technique is different. The diamond starts in a powdery form that is sintered onto a carbide plate using cobalt as a solvent metal substrate. This is done at an extreme temperature and pressure as the cobalt infiltrates the powder, causing the grains to grow together. This effectively creates a thick diamond wafer, between 010” and .030” in width, with a carbide base. This carbide base is then brazed onto the head an end mill and sharpened.

PCD Diamond CoatingHow Diamond Coatings Differ

Coating Hardness & Thickness

Polycrystalline tools (CVD or sintered) have a much higher hardness, thickness, and max working temperature than Amorphous Diamond oated tools. As mentioned previously, a PCD tool consists of a diamond wafer brazed to a carbide body while a CVD tool is a carbide end mill with a relatively thick layer of polycrystalline diamond grown into it. This grown layer causes the CVD tools to have a rounded cutting edge compared to PCD and Amorphous Diamond coated tools. PCD tools have the thickest diamond layer that is ground to a sharp edge for maximum performance and tool life. The difference between PCD tools and CVD coated tools lies in the thickness of this coat and the sharpness of the cutting edge. Amorphous Diamond tools maintain a sharper edge than CVD coated tools because of their thin coating.

Flute Styles

Harvey Tool’s line of PCD end mills are all straight fluted, CVD coated tools are all helically fluted, and Amorphous Diamond tools are offered in a variety of options. The contrast between straight fluted and helically fluted can be seen in the images below, PCD (top) and CVD (bottom). Electrical discharge machining, grinding or erosion are used cut the PCD wafer to the specifications. The size of this wafer limits the range of diameters that can be achieved during manufacturing. In most situations a helically fluted tool would be preferred over a straight fluted tool but with true diamond tooling that is not the case. The materials that PCD tools and CVD coated tools are typically used to cut produce a powdery chip that does not require the same evacuation that a metallic or plastic chip necessitates.

PCD Diamond end mill

PCD Ball End Mill

CVD Diamond end mill

CVD Ball End Mill

Proper Uses

CVD tools are ideally suited for abrasive material not requiring a sharp cutting edge – typically materials that produce a powdery chip such as composites and graphite. Amorphous Diamond tools have a broad range of non-ferrous applications spanning from carbon fiber to precious metals but ceramics are typically outside their range as they can be too abrasive and wear away the coating. PCD tools overlap their CVD and DLC coated counterparts as they can be used for any non-ferrous abrasive material.

Cut to the Point

Harvey Tool carries physical vapor deposition diamond-like carbon coated tools, chemical vapor deposition diamond tools and polycrystalline diamond tools. PCD tools are composed of the thickest diamond wafer brazed onto a carbide shank and are ground to a sharp edge. CVD coated tools have the diamond grown into a carbide end mill. Amorphous Diamond coated tools have the DLC coated onto them through the PVD process. For more information on the diamond coating best suited for your operation, contact a Harvey Tool Tech Team Member for immediate help.

Attacking Aluminum: A Machining Guide

Aluminum is one of the most commonly machined materials, as most forms of the material feature excellent machinability, and is thus a commonly used material in manufacturing. Because of this, the competition for aluminum machining can be intense. Understanding the basics behind tool selection, running parameters, and advanced milling techniques for aluminum can help machinists earn a competitive advantage.

Material Properties

Aluminum is a highly formable, workable, lightweight material. Parts made from this material can be found in nearly every industry. Additionally, Aluminum has become a popular choice for prototypes due to its low-cost and flexibility.

Aluminum is available in two basic forms: Cast and Wrought. Wrought Aluminum is typically stronger, more expensive, and contains a lower percentage of outside elements in its alloys. Wrought Aluminum is also more heat-resistant than Cast and has a higher level of machinability.

Cast Aluminum has less tensile strength but with a higher flexibility. It costs less, and has higher percentages of outside elements (silicon, magnesium, etc.) in its alloys, making it more abrasive than Wrought.

Tool Geometry

There are a few coating options available for Aluminum tooling, including the popular gold-colored ZrN (Zirconium Nitride) and the lesser known but highly effective TiB2 (Titanium Diboride). Uncoated tooling can also provide solid machining performance. However, the real key to high performance machining in Aluminum is knowing the proper flute count and helix angle required for your operation.

Flute Count

End mills for aluminum are often available in either 2 flute or 3 flute styles. With higher flute counts, it would become difficult to evacuate chips effectively at the high speeds at which you can run in aluminum. This is because aluminum alloys leave a large chip, and chip valleys become smaller with each additional flute on an end mill.

flute count for aluminum

Traditionally, 2 flute end mills have been the preferred choice for Aluminum. However, 3 flute end mills have proven to be more successful in many finishing operations, and with the right parameters they can also work successfully as roughers. While much of the debate between 2 and 3 flute end mills for Aluminum boils down to personal preference, the operation, rigidity, and desired material removal rates can also have an effect on tool selection.

Helix Angles

The helix angle of a tool is measured by the angle formed between the centerline of the tool and a straight line tangent along the cutting edge. Cutting tools for aluminum typically feature higher helix angles than standard end mills. Specialized helix angles for Aluminum are typically either 35°, 40°, or 45°. Variable helix tools are also available and make a great choice for reducing chatter and harmonics while also increasing material removal rates.

Aluminum Machining

A helix angle of 35° or 40° is a good choice for traditional roughing and slotting applications. A 45° helix angle is the preferred choice for finishing, but also for High Efficiency Milling toolpaths as the high helix angle wraps around the tool faster and makes for a more aggressive cut.

Tooling Options

When machining aluminum, standard 2 or 3 flute tools will often get the job done. However, for certain applications and machine setups there are some more tooling options to consider for even better performance.

Chipbreaker Tooling

One of the most important things to consider when machining aluminum (and many other materials) is effective chip evacuation. Standard 2-3 flute end mills running at recommended speeds and feeds and proper chip loads can evacuate chips fairly well. However, 3 flute chipbreaker tooling can run at increased speed and feed rates for even better performance. The unique offset chip breaker geometry creates smaller chips for optimal evacuation while still leaving a semi-finished surface.

Chipbreaker Aluminum

These tools are excellent for more advanced toolpaths like High Efficiency Milling, which is another important tool for a successful aluminum machining experience.

High Balance End Mills

High balance end mills are designed to significantly increase performance in highly balanced machining centers capable of elevated RPMs and feed rates. These tools are precision balanced specifically for high velocity machining in aluminum (up to 33,000 RPM).

High Balance Tools for Aluminum

Helical Solutions offers high balance tooling in standard 2 flute styles, as well as coolant-through 3 flute styles for reduced heat, enhanced chip evacuation, and increased material removal rates. These tools, like the chipbreakers, are also an excellent choice for High Efficiency Milling toolpaths.

Running Parameters

Setting the right parameters for aluminum applications is vital to optimizing productivity and achieving better machining results. Since aluminum is an easier material to machine, pushing your machine to its limits and getting the most out of your tool is vital to stay ahead of the competition and keep winning business.

While there are many factors that go into the parameters for every job, there are some general guidelines to follow when machining aluminum. For cast aluminum alloys (i.e. 308, 356, 380), a surface footage of 500-1000 SFM is recommended, with RPMs varying based on cutter diameter. The basic calculation to find a starting point for RPMs would be (3.82 x SFM) / Diameter.

In wrought aluminum alloys (i.e. 2024, 6061, 7075), a surface footage of 800-1500 SFM is recommended, with the same calculation being used to find a starting point for RPMs.

High Efficiency Milling

High Efficiency Milling, commonly known as HEM, is a strategy that is rapidly gaining popularity in the manufacturing industry. Many CAM programs are now including HEM toolpaths, and while virtually any machine can perform HEM, the CNC controller must feature a fast processor to keep up with the additional lines of code. A great example of High Efficiency Milling toolpaths in Aluminum can be seen below.

At its core, HEM is a roughing technique that utilizes a low Radial Depth of Cut (RDOC) and a high Axial Depth of Cut (ADOC) to take full advantage of the cutting edge of the tool. To learn more about how High Efficiency Milling can increase your efficiency, extend your tool life to keep costs down, and get greater performance for aluminum (and other materials), click here to download the HEM Guidebook.

In Summary

Aluminum is a versatile material with a high level of machinability, but it should not be overlooked. Understanding the best ways to tackle it is important for achieving the desired results. Optimizing your tool crib, machine setups, and toolpaths for aluminum is essential to stay ahead of the competition and make your shop more efficient.

Selecting the Right Harvey Tool Miniature Drill

Among Harvey Tool’s expansive holemaking solutions product offering are several different types of miniature tooling options and their complements. Options range from Miniature Spotting Drills to Miniature High Performance Drills – Deep Hole – Coolant Through. But which tools are appropriate for the hole you aim to leave in your part? Which tool might your current carousel be missing, leaving efficiency and performance behind? Understanding how to properly fill your tool repertoire for your desired holemaking result is the first step toward achieving success.

Pre-Drilling Considerations

Miniature Spotting Drills

Depending on the depth of your desired machined hole and its tolerance mandates, as well as the surface of the machine you will be drilling, opting first for a Miniature Spotting Drill might be beneficial. This tool pinpoints the exact location of a hole to prevent common deep-hole drilling mishaps such as walking, or straying from a desired path. It can also help to promote accuracy in instances where there is an uneven part surface for first contact. Some machinists even use Spotting Drills to leave a chamfer on the top of a pre-drilled hole. For extremely irregular surfaces, however, such as the side of a cylinder or an inclined plane, a Flat Bottom Drill or Flat Bottom Counterbore may be needed to lessen these irregularities prior to the drilling process.

spotting drill

Tech Tip: When spotting a hole, the spot angle should be equal to or wider than the angle of your chosen miniature drill. Simply, the miniature drill tip should contact the part before its flute face does.

spotting drill correct angle

Selecting the Right Miniature Drill

Harvey Tool stocks several different types of miniature drills, but which option is right for you, and how does each drill differ in geometry?

Miniature Drills

Harvey Tool Miniature Drills are popular for machinists seeking flexibility and versatility with their holemaking operation. Because this line of tooling is offered uncoated in sizes as small as .002” in diameter, machinists no longer need to compromise on precision to reach very micro sizes. Also, this line of tooling is designed for use in several different materials where specificity is not required.

miniature drill

Miniature High Performance Drills – Deep Hole – Coolant Through

For situations in which chip evacuation may be difficult due to the drill depth, Harvey Tool’s Deep Hole – Coolant Through Miniature Drills might be your best option. The coolant delivery from the drill tip will help to flush chips from within a hole, and prevent heeling on the hole’s sides, even at depths up to 20 multiples of the drill diameter.

miniature drill coolant through

Miniature High Performance Drills – Flat Bottom

Choose Miniature High Performance Flat Bottom Drills when drilling on inclined and rounded surfaces, or when aiming to leave a flat bottom on your hole. Also, when drilling intersecting holes, half holes, shoulders, or thin plates, its flat bottom tool geometry helps to promote accuracy and a clean finish.

flat bottom drill

Miniature High Performance Drills – Aluminum Alloys

The line of High Performance Drills for Aluminum Alloys feature TiB2 coating, which has an extremely low affinity to Aluminum and thus will fend off built-up edge. Its special 3 flute design allows for maximum chip flow, hole accuracy, finish, and elevated speeds and feeds parameters in this easy-to-machine material.

drill for aluminum

 

Miniature High Performance Drills – Hardened Steels

Miniature High Performance Drills – Hardened Steels features a specialized flute shape for improved chip evacuation and maximum rigidity. Additionally, each drill is coated in AlTiN Nano coating for hardness, and heat resistance in materials 48 Rc to 68 Rc.

drill for hardened steel

Miniature High Performance Drills – Prehardened Steels

As temperatures rise during machining, the AlTiN coating featured on Harvey Tool’s Miniature High Performance Drills – Prehardened Steels creates an aluminum oxide layer which helps to reduce thermal conductivity of the tool and helps to promote heat transfer to the chip, as well as improve lubricity and heat resistance in ferrous materials.

drill for prehardened steel

Post-Drilling Considerations

Miniature Reamers

For many operations, drilling the actual hole is only the beginning of the job. Some parts may require an ultra-tight tolerance, for which a Miniature Reamer (tolerances of +.0000″/-.0002″ for uncoated and +.0002″/-.0000″ for AlTiN Coated) can be used to bring a hole to size. miniature reamer

Tech Tip: In order to maintain appropriate stock removal amounts based on the reamer size, a hole should be pre-drilled at a diameter that is 90-94 percent of the finished reamed hole diameter.

Flat Bottom Counterbores

Other operations may require a hole with a flat bottom to allow for a superior connection with another part. Flat Bottom Counterbores leave a flat profile and straighten misaligned holes. For more information on why to use a Flat Bottom Counterbore, read 10 Reasons to Use Flat Bottom Tools.

flat bottom counterbores

Key Next Steps

Now that you’re familiar with miniature drills and complementary holemaking tooling, you must now learn key ways to go about the job. Understanding the importance of pecking cycles, and using the correct approach, is vital for both the life of your tool and the end result on your part. Read this post’s complement “Choosing the Right Pecking Cycle Approach,” for more information on the approach that’s best for your application.

Choosing The Right Pecking Cycle Approach

Utilizing a proper pecking cycle strategy when drilling is important to both the life of your tool and its performance in your part. Recommended pecking cycles vary depending on the drill being used, the material you’re machining, and your desired final product.

What are Pecking Cycles?

Rather than drill to full drill depth in one single plunge, pecking cycles involve several passes – a little at a time. Pecking aids the chip evacuation process, helps support tool accuracy while minimizing walking, prevents chip packing and breakage, and results in a better all around final part.

Recommended Pecking Cycles / Steps

Miniature Drills

miniature drill pecking cycles

High Performance Drills – Flat Bottom

pecking cycles

High Performance Drills – Aluminum & Aluminum Alloys

aluminum pecking cycles

Note: For hole depths 12x or greater, a pilot hole of up to 1.5X Diameter is recommended.

High Performance Drills – Hardened Steels

hardened steels pecking cycles
High Performance Drills – Prehardened Steels

prehardened steels pecking cycles

Key Pecking Cycle Takeaways

From the above tables, it’s easy to identify how recommended pecking cycles change based on the properties of the material being machined. Unsurprisingly, the harder the material is, the shorter the recommended pecking depths are. As always, miniature drills with a diameter of less than .010″ are extremely fragile and require special precautions to avoid immediate failure. For help with your specific job, contact the Harvey Tool Technical Team at 800-645-5609 or [email protected]

8 Ways You’re Killing Your End Mill

1. Running It Too Fast or Too Slow

Determining the right speeds and feeds for your tool and operation can be a complicated process, but understanding the ideal speed (RPM) is necessary before you start running your machine. Running a tool too fast can cause suboptimal chip size or even catastrophic tool failure. Conversely, a low RPM can result in deflection, bad finish, or simply decreased metal removal rates. If you are unsure what the ideal RPM for your job is, contact the tool manufacturer.

2. Feeding It Too Little or Too Much

Another critical aspect of speeds and feeds, the best feed rate for a job varies considerably by tool type and workpiece material. If you run your tool with too slow of a feed rate, you run the risk of recutting chips and accelerating tool wear. If you run your tool with too fast of a feed rate, you can cause tool fracture. This is especially true with miniature tooling.

3. Using Traditional Roughing

high efficiency milling

While traditional roughing is occasionally necessary or optimal, it is generally inferior to High Efficiency Milling (HEM). HEM is a roughing technique that uses a lower Radial Depth of Cut (RDOC) and a higher Axial Depth of Cut (ADOC). This spreads wear evenly across the cutting edge, dissipates heat, and reduces the chance of tool failure. Besides dramatically increasing tool life, HEM can also produce a better finish and higher metal removal rate, making it an all-around efficiency boost for your shop.

4. Using Improper Tool Holding

tool holding

Proper running parameters have less of an impact in suboptimal tool holding situations. A poor machine-to-tool connection can cause tool runout, pullout, and scrapped parts. Generally speaking, the more points of contact a tool holder has with the tool’s shank, the more secure the connection. Hydraulic and shrink fit tool holders offer increased performance over mechanical tightening methods, as do certain shank modifications, like Helical’s ToughGRIP shanks and the Haimer Safe-Lock™.

5. Not Using Variable Helix/Pitch Geometry

variable helix

A feature on a variety of high performance end mills, variable helix, or variable pitch, geometry is a subtle alteration to standard end mill geometry. This geometrical feature ensures that the time intervals between cutting edge contact with the workpiece are varied, rather than simultaneous with each tool rotation. This variation minimizes chatter by reducing harmonics, which increases tool life and produces superior results.

6. Choosing the Wrong Coating

end mill coatings

Despite being marginally more expensive, a tool with a coating optimized for your workpiece material can make all the difference. Many coatings increase lubricity, slowing natural tool wear, while others increase hardness and abrasion resistance. However, not all coatings are suitable to all materials, and the difference is most apparent in ferrous and non-ferrous materials. For example, an Aluminum Titanium Nitride (AlTiN) coating increases hardness and temperature resistance in ferrous materials, but has a high affinity to aluminum, causing workpiece adhesion to the cutting tool. A Titanium Diboride (TiB2) coating, on the other hand, has an extremely low affinity to aluminum, and prevents cutting edge build-up and chip packing, and extends tool life.

7. Using a Long Length of Cut

optimal length of cut

While a long length of cut (LOC) is absolutely necessary for some jobs, especially in finishing operations, it reduces the rigidity and strength of the cutting tool. As a general rule, a tool’s LOC should be only as long as needed to ensure that the tool retains as much of its original substrate as possible. The longer a tool’s LOC the more susceptible to deflection it becomes, in turn decreasing its effective tool life and increasing the chance of fracture.

8. Choosing the Wrong Flute Count

flute count

As simple as it seems, a tool’s flute count has a direct and notable impact on its performance and running parameters. A tool with a low flute count (2 to 3) has larger flute valleys and a smaller core. As with LOC, the less substrate remaining on a cutting tool, the weaker and less rigid it is. A tool with a high flute count (5 or higher) naturally has a larger core. However, high flute counts are not always better. Lower flute counts are typically used in aluminum and non-ferrous materials, partly because the softness of these materials allows more flexibility for increased metal removal rates, but also because of the properties of their chips. Non-ferrous materials usually produce longer, stringier chips and a lower flute count helps reduce chip recutting. Higher flute count tools are usually necessary for harder ferrous materials, both for their increased strength and because chip recutting is less of a concern since these materials often produce much smaller chips.

What You Need to Know About Coolant for CNC Machining

Coolant in purpose is widely understood – it’s used to temper high temperatures common during machining, and aid in chip evacuation. However, there are several types and styles, each with its own benefits and drawbacks. Knowing which coolant – or if any – is appropriate for your job can help to boost your shop’s profitability, capability, and overall machining performance.

Coolant or Lubricant Purpose

Coolant and lubricant are terms used interchangeably, though not all coolants are lubricants. Compressed air, for example, has no lubricating purpose but works only as a cooling option. Direct coolants – those which make physical contact with a part – can be compressed air, water, oil, synthetics, or semi-synthetics. When directed to the cutting action of a tool, these can help to fend off high temperatures that could lead to melting, warping, discoloration, or tool failure. Additionally, coolant can help evacuate chips from a part, preventing chip recutting and aiding in part finish.

Coolant can be expensive, however, and wasteful if not necessary. Understanding the amount of coolant needed for your job can help your shop’s efficiency.

Types of Coolant Delivery

Coolant is delivered in several different forms – both in properties and pressure. The most common forms include air, mist, flood coolant, high pressure, and Minimum Quantity Lubricant (MQL). Choosing the wrong pressure can lead to part or tool damage, whereas choosing the wrong amount can lead to exhausted shop resources.

Air: Cools and clears chips, but has no lubricity purpose. Air coolant does not cool as efficiently as water or oil-based coolants. For more sensitive materials, air coolant is often preferred over types that come in direct contact with the part. This is true with many plastics, where thermal shock – or rapid expansion and contraction of a part – can occur if direct coolant is applied.

Mist: This type of low pressure coolant is sufficient for instances where chip evacuation and heat are not major concerns. Because the pressure applied is not great in a mist, the part and tool do not undergo additional stresses.

Flood (See Video Below): This low pressure method creates lubricity and flushes chips from a part to avoid chip recutting, a common and tool damaging occurrence.

High Pressure (See Video Below): Similar to flood coolant, but delivered in greater than 1,000 psi. This is a great option for chip removal and evacuation, as it blasts the chips away from the part. While this method will effectively cool a part immediately, the pressure can be high enough to break miniature diameter tooling. This method is used often in deep pocket or drilling operations, and can be delivered via coolant through tooling, or coolant grooves built into the tool itself. Harvey Tool offers Coolant Through Drills and Coolant Through Threadmills.

Minimum Quantity Lubricant (MQL): Every machine shop focuses on how to gain a competitive advantage – to spend less, make more, and boost shop efficiency. That’s why many shops are opting for MQL, along with its obvious environmental benefits. Using only the necessary amount of coolant will dramatically reduce costs and wasted material. This type of lubricant is applied as an aerosol, or an extremely fine mist, to provide just enough coolant to perform a given operation effectively.

In Conclusion

Coolant is all-too-often overlooked as a major component of a machining operation. The type of coolant or lubricant, and the pressure at which it’s applied, is vital to both machining success and optimum shop efficiency. Coolant can be applied as compressed air, mist, in a flooding property, or as high pressure. Certain machines also are MQL able, meaning they can effectively restrict the amount of coolant being applied to the very amount necessary to avoid being wasteful.