How to Advance Your Machining Career: 8 Tips From Machining Pros

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Since we began shining a light on Harvey Performance Company brand customers via “In the Loupe’s,” Featured Customer posts, more than 20 machinists have been asked to share insight relevant to how they’ve achieved success in advancing their machining career. Each Featured Customer post includes interesting and useful information on a variety of machining-related subjects, including prototyping ideas, expanding a business, getting into machining, advantages and disadvantages of utilizing different milling machine types, and more. This post compiles 8 useful tips from our Featured Customers on ways to advance your machining career.

Tip 1: Be Persistent – Getting Your Foot in the Door is Half the Battle

With machining technology advancing at the amazing rate that it is, there is no better time to become a machinist. It is a trade that is constantly improving, and offers so many opportunities for young people. Eddie Casanueva of Nueva Precision first got into machining when he was in college, taking a job at an on-campus research center for manufacturing systems to support himself.

“The research center had all the workings of a machine shop,” Eddie said. “There were CNC mills, lathes, injection molding machines, and more. It just looked awesome. I managed to get hired for a job at minimum wage sweeping the shop floor and helping out where I could.

As a curious student, I would ask a million questions… John – an expert machinist – took me under his wing and taught me lots of stuff about machining. I started buying tools and building out my toolbox with him for a while, absorbing everything that I could.”

One of the best things about becoming a machinist is that there is a fairly low entry barrier. Many machinists start working right out of high school, with 12-18 months of on-the-job training or a one to two year apprenticeship. Nearly 70% of the machinist workforce is over the age of 45. The Bureau of Labor Statistics is predicting a 10% increase in the machinist workforce with opportunities for 29,000 additional skilled machinists by 2024, so it is certainly a great time to get your foot in the door.

Tip 2: Keep an Open Mind – If You Can Think of It, You Can Machine It

Being open-minded is crucial to becoming the best machinist you can be. By keeping an open mind, Oklahoma City-based company Okluma’s owner Jeff Sapp has quickly earned a reputation for his product as one of the best built and most reliable flashlights on the market today. Jeff’s idea for Okluma came to him while riding his motorcycle across the country.

“I had purchased what I thought was a nice flashlight for $50 to carry with me on the trip. However, two days in to the trip the flashlight broke. Of course, it was dark and I was in the middle of nowhere trying to work on my bike. I’m happy to pay for good tools, but that wasn’t what happened. Not only was there no warranty for replacement, there was no way to fix it. It was just made to be thrown away. That whole attitude makes me angry. When I got home, I decided I was going to put my new skills to work and design and build my own flashlight, with the goal of never running into an issue like I had on my trip ever again. I started by making one for myself, then four, then twenty. That was four years ago. Now I have my own business with one employee and two dogs, and we stay very busy.”

An awesome side benefit to working as a machinist is that you have all the resources to create anything you can dream of, like Jeff did with Okluma.

machining career

Image courtesy of Okluma.

Tip 3: Be Patient – Take Time to Ensure Your Job is Setup Correctly before Beginning

The setup process is a huge part of machining, but is often overlooked. Alex Madsen, co- owner of M5 Micro in Minnesota, has been working in manufacturing for more than 11 years. Alex is also a part owner of World Fabrication, and owns his own job shop called Madsen Machine and Design. Alex has spent countless hours perfecting his setup to improve his part times.

“It is certainly challenging to use little tools, but the key is to not get discouraged. You should plan on lots of trial and error; breaking tools is just a part of the game. You may buy ten end mills and break six, but once you dial one in it will last the rest of the job.

You should also make sure to put extra time and effort into understanding your machine when working on micromachining jobs. You need to know where there is any backlash or issues with the machine because with a tiny tool, even an extra .0003” cut can mean the end of your tool. When a difference of one tenth can make or break your job, you need to take your time and be extra careful with your machine, tool inspection, and programming before you hit run.”

Tip 4: Effort Pays Off In Your Machining Career – Long Hours Result in Shop Growth

Success isn’t earned overnight. That is especially true in the machining world. Becoming a good machinist takes a great deal of sacrifice, says Josh from Fleet Machine Co. in Gloucester, MA.

“Opening your own shop involves more than learning how to program and machine. You also need to be willing to sacrifice some of your free time by working long hours to build your business from the ground up. Being a great machinist is important, but you also need to understand the basics of business, and you need to be able to sell your service and maintain a certain level of quality to keep your customers coming back.”

Working hard is a common theme we hear from our featured customers. Brothers Geordan and Nace Roberts of Master Machine Manufacturing have similar advice.

“We often need to work odd hours of the day to maintain the business, but we do it in a way that makes sure we have our family time. There are many times where we will go home, have dinner and hang out with the family, and wait until they are all sleeping to go back to work until two or three a.m. We will get back home later that morning to sleep a little and have breakfast with the family and send them on their way before heading back into the shop.” Starting and growing a business takes time. Every machinist starts from the beginning and through hard work and determination, grows their business.

Liberty Machine cnc mill

Image courtesy of Liberty Machine Inc.

Tip 5: Utilize Tooling from Quality Manufacturers – All Tooling Isn’t Created Equal

When it comes down to it, tooling is singlehandedly the biggest choice you will make in your machining career. Grant Hughson, manufacturing engineer at Weiss Watch Company who works as a manufacturing instructor in his spare time, reflected on the importance of tooling.

“Tool to tool accuracy and performance is vital in this business, especially with our extremely tight tolerances. High quality tools make sure that we get the same performance time after time without needing to scrap parts. This saves us valuable time and money.”

While opting for cheaper tooling can appear to be beneficial when just starting out, before long, machinists are losing time and money because of unpredictability. Jonathan from TL Technologies echoed this point, saying:

“We feel that if we invested so much in these high-end machining centers, it would be criminal to put insufficient tooling and holders into them. We found that by selecting the proper tool with the appropriate sciences behind it we have been able to create products with a cost per cut that is not only competitive, but required to stay current. By keeping the quality as high as possible on the part making side of things, we’ve insured as much ease and reliability into our downstream process as we could. Quality tooling also provides predictability and added safety into the workflow. High-quality carbide tooling is the lifeblood of the business.”

Additional Thoughts Regarding Boosting Your Machining Career With Tooling:

Don’t Cheap Out

  • “The additional cost is always worth the payoff in the end knowing that you have a tool that will produce quality parts and shave valuable minutes off your cycle times. The slightly higher cost of the Harvey/Helical product is small change compared to the long term cost savings associated with their performance” – Seth, Liberty Machine

Consistency is Key

  • “We know the performance we are going to get from the tools is consistent, and we can always rely on getting immaculate finishes. While using the Harvey Tool and Helical product, we can confidently walk away from the machine and come back to a quality finished part every time.” – Bennett, RIT Baja SAE

Superior Specialty Tools

  • “One of the greatest things that I’ve experienced over the past year and a half is flexibility. We’ve asked for some specific tools to be made typically, the lead times that we found were beyond what we needed. We went through the Helical specials division and had them built within a couple of weeks. That was a game changer for us.” – Tom, John Force Racing

“Having high quality tooling like Helical is essential. Helical tools help us maintain a much higher machining efficiency because of the outstanding tool life, while also achieving more aggressive run times. In addition, we are able to consistently keep high tolerances, resulting in a better final product.” – Cameron, Koenig Knives

Tip 6: Get With the Times – Join the Social Media Community

Social media is a valuable tool for machinists. With ever-increasing popularity in networks such as Facebook, LinkedIn, Twitter, and Instagram, there will always be an audience to showcase new and unique products to. We asked a few of our featured customers how they incorporated social media into their machining career and the benefits that come along with it.

“A lot of our sales come through Instagram or Facebook, so I would recommend those platforms to anyone who is trying to start a business,” Jeff from Okluma said. “We have also had a lot of success collaborating with others in the community. Typically it is something we couldn’t do ourselves, or they couldn’t do themselves, so we share the labor and collaborate on some really cool items.”

Tip 7: Value Your Customers – Always Put Them First

“In the Loupe’s” featured customers repeatedly emphasized the importance of putting customers first. It’s a simple concept to master, and pays off immensely as you advance in your machining career. Repeat customers tell you that you are doing something right, said Brian Ross, owner of Form Factory.

“We have kept our customers happy and consistently deliver parts on time, so we get a lot of repeat business. Word definitely gets around on how you treat people so we try to treat everyone with respect and honesty which is key to running a good business.” Jeff from Okluma takes great pride in his customer service, saying “we only sell direct to consumers through our website so we can control our lifetime warranty. It has worked really well for us so far, so we have no plans to change that right now. I care more about our customers than any retailer is able to.”

man examining machined part for machining career

Image courtesy of MedTorque.

Tip 8: Never Stop Learning – Ask Questions Whenever You Can as Your Machining Career Advances

Hopefully some of these tips from our featured customers stuck with you in exploring a machining career. To leave you with a quote from of Seth Madore, owner of Liberty Machine, “Don’t stop learning. Keep your ears open and your mouth shut,” “That old guy in the shop has likely forgotten more than you will ever learn. The amount of tools in your Kennedy box doesn’t mean you’re a good machinist. Some of the best toolmakers I knew had small boxes with only the common tools. Learn how to excel with limited resources. Ask questions, and own up to your mistakes.”

When to and Not to Use Drop Hole Allowance

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Dovetail Cutters are cutting tools that create a trapezoidal-type shape, or a dovetail groove, in a part. Due to the form of these tools, special considerations need to be made in order to achieve long tool life and superior results. This is particularly true when machining O-ring grooves, as this operation requires the tool to drop into the part to begin cutting. Using an appropriate tool entry method, specifically understanding when drop hole allowance is (and is not) needed, is important to keep common dovetail mishaps from occurring.

What is a Drop-Hole?

When designing parts featuring O-ring grooves, the consideration of drop-hole allowance is a pivotal first step. A drop-hole is an off-center hole milled during the roughing/slotting operation. This feature allows for a significantly larger, more rigid tool to be used. This is because the cutter no longer has to fit into the slot, but into a hole with a diameter larger than its cutter diameter.

graphic showing holes with and without drop hole allowance

Why consider adding a Drop-Hole?

When compared to tools without drop-hole allowance, tools with drop-hole allowance have a much larger neck diameter-to-cutter diameter ratio. This makes the drop-hole tools far stronger, permitting the tool to take heavy radial depths of cut and fewer step-overs. Using a drop-hole will allow the use of the stronger tool, which will increase production rate and improve tool life.

Machining Operation with Drop-Hole Allowance

5 unique machining operations with drop hole allowance

A maximum of 4 radial passes per side are needed.

When Not to Drop Hole

Drop-holes are sometimes not permitted in a design due to the added stress concentration point it leaves. Common examples for where a drop-hole would not be allowed include:

  • In high pressure applications
  • In seals requiring a high reliability
  • Where dangerous or hazardous fluids are being used

The issue with drop-hole allowance is that the additional clearance used for tool entry can create a weak spot in the seal, which can then become compromised under certain conditions. Ultimately, drop-hole allowance requires approval from the customer to ensure the application allows for it.

Machining Operation Without Drop-Hole Allowance

machining operations without drop hole allowance

A maximum of 20 radial passes per side are needed.

Drop-Hole Placement

When adding a drop-hole to your part, it is important to ensure that the feature is placed correctly to maximize seal integrity. Per the below figure, the drop-hole should be placed off center of the groove, ensuring that only one side of the groove is affected.

proper placement of hole when using drop hole allowance

It is also necessary to ensure that drop-hole features are put on the correct side of the groove. Since O-rings are used as a seal between pressures, it is important to have the drop-hole bordering the high pressure zone. As pressure moves from high to low, the O-ring will be forced into the fully supported side, allowing for a proper seal (See image below).

graphic showing the use of a drop hole for o-ring seals between high and low pressure areas

Chipbreaker vs. Knuckle Rougher End Mills

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Knuckle Roughers and Chipbreakers are common profiles found on roughing end mills that, while fairly similar in appearance, actually serve different functions. Chipbreakers refer to the notches along the cutting edge of a tool that work to break up chips to prevent common evacuation mishaps. Knuckle Roughers refer to the serrated cutting edge of a tool, which works to enhance cutting action for an overall smoother operation.

Determining the appropriate style of tool is a very important first step to a successful roughing application.

Increase Your Roughing Efficiency With Helical Solutions’ Chipbreakers

Understanding the Two Styles

Chipbreaker End Mills

To aid chip evacuation, Chipbreaker End Mills feature a notched profile along the cutting edge that break down long chips into smaller, more manageable pieces. These tools are often utilized in aluminum jobs, as long, stringy chips are common with that material.

Each notch is offset flute-to-flute to enhance the surface finish on the part. This works by ensuring that as each flute rotates and impacts a part, following flutes work to clean up any marks or extra material that was left behind by the first pass. This leaves a semi-finished surface on your part.

chipbreaker end mill standing straight up

In addition to improving chip control and reducing cutting resistance, these tools also help in decreasing heat load within the chips. This delays tool wear along the cutting edge and improves cutting performance. Not only are these tools great for hogging out a great deal of material, but they can be utilized in a wide array of jobs – from aluminum to steels. Further, a machinist can take full advantage of the unique benefits this tool possesses by utilizing High Efficiency Milling toolpaths, meant to promote efficiency and boost tool life.

Knuckle Roughers

Knuckle Rougher End Mills have a serrated cutting edge that generates significantly smaller chips than a standard end mill cutting edge. This allows for smoother machining and a more efficient metal removal process, similar to Chipbreaker End Mills. However, the serrations chop the chips down to much finer sizes, which allows more chips into the flutes during the evacuation process without any packing occurring.

straight up black knuckle rougher end mill

Designed for steels, Knuckle Rougher End Mills are built to withstand harder materials and feature a large core. Because of this, these tools are great for roughing out a lot of material. However, due to the profile on the cutting edge, tracks along the wall can sometimes be left on a part. If finish is a concern, be sure to come in with a finishing tool after the roughing operation. Knuckle Roughers have proven the ability to run at higher chip loads, compared to similar end mills, which makes this a highly desired style for roughing. Further, this style of rougher causes a lot of heat and friction within the chips, so it’s important to run flood coolant when running this tool.

Key Differences Between Knuckle Roughers & Chipbreakers

While the two geometries offer similar benefits, it’s important to understand the distinct differences between them. Chipbreakers feature offset notches, which help to leave an acceptable finish on the walls of a part. Simply, the material left on an initial flute pass is removed by subsequent passes. A Knuckle Rougher does not feature this offset geometry, which can leave track marks on your part. Where part finish is of upmost importance, utilize a Knuckle Rougher to first hog out a great deal of steel, and work a final pass with a Finishing End Mill.

A unique benefit of Knuckle Roughers is the grind they possess – a cylindrical grind, compared to a relieved grind of a Chipbreaker End Mill. Because of this, Knuckle Roughers are easier to resharpen. Therefore, instead of buying a new tool, resharpening this profile is often a cheaper alternative.

How Material Specific Tooling Pays Off

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A machinist is faced with many questions while selecting the proper tool for their job. One key decision that must be made is whether a material specific tool is appropriate and necessary for the application that’s going to be performed – whether the benefits of using this type of tool outweigh the higher price tag than that of a tool designed for use in a variety of materials. There are four main categories to consider when deciding whether a material specific tool is your best bet: internal tool geometry, coatings, material removal rates (MRR), and cost.

When to Utilize Material Specific Tooling

Are you a machinist in a shop that deals primarily with one type of material? Or, do you generally change materials frequently throughout the day? Further, how many parts do you make at a time? These are questions you must ask yourself prior to making a tooling decision.

Material Specific Tooling is best utilized where several parts are being machined of the same material. For instance, if your shop is machining 1,000 plastic parts, it would be in your best interest to opt for a tool designed for this material as your tooling would not only last longer but perform better. If machining flexibility is paramount for your shop, if you’re only machining a few parts, or if part finish is not of high importance, a regular end mill may suffice.

Pros and Cons of Material Specific Tooling

There are pros and cons to purchasing a Material Specific Tool.

Pros:

  • Tool geometry designed for the material you’re working in to achieve the best results.
  • Coating optimized for the material you’re cutting.
  • More aggressive speeds and feeds, and boosted MRR as a result.
  • Increased tool life.

Cons:

  • Higher upfront cost, though long term savings are possible if used in proper situations.
  • Less opportunity for flexibility. While most end mills may be suitable for use in many jobs and many machines, Material Specific End Mills are engineered for use in specific materials

Special Benefits of Material Specific Tooling

A Unique Internal Tool Geometry

Many manufacturers supply tooling designed for use in specific material buckets. For instance, Harvey Tool has distinct catalog sections for material specific tooling for Hardened Steels, Exotic Alloys, Medium Alloy Steels, Free Machining Steels, Aluminum Alloys, Plastics, Diamond Tooling for Non-Ferrous Materials, and Composites. The special geometry of tools found in these sections is optimized to allow the tool to perform optimally in its select material group.

For instance, a machinist may be faced with a dilemma while preparing to machine a plastic part. While an end mill found in Harvey Tool’s Miniature End Mill section could certainly machine this material, Harvey Tool’s end mill offering designed to machine plastics feature a high rake, high relief design. This is ideal for plastics because you want to effectively cut and form chips while the strength of the tool is less of a concern. The high rake and high relief creates a sharp cutting edge that would quickly break down in metals. However, in plastics, this effectively shears the material and transfers the heat into the chip to produce a great finish in your part.

single flute end mill for pastics

Harvey Performance Company, LLC.

Specific Coatings & Substrates for Optimal Performance

One key benefit of opting for a material specific tool is the ability to utilize the best coating option available for that material. Tool coatings serve many functions, including improved lubricity, increased tool life, and a higher-quality part finish. In addition, coated tools can typically be run around 10% faster than uncoated tools.

While many manufacturers will specially coat a standard end mill at your request, this takes added time and cost. In its Material Specific catalog sections, Harvey Tool offers coated tools stocked and ready to ship. For instance, their Hardened Steels and Exotic Alloys categories utilize AlTiN Nano coating. This is a unique nanocomposite coating that has a max working temperature of 2,100° F and shows improved performance in materials such as Hardened Steels, Titanium Alloys, and Inconel, among others.

Increased Material Removal Rates

Because Material Specific Tooling features optimal tool geometry for a job, running parameters are generally able to be more aggressive. Any machinist knows that Material Removal Rates (MRR), is the metric that’s most closely related to shop efficiency, as the more material removed from a part in a given period of time, the faster parts are made and the higher the shop output.

The following example compares running parameters of end mills from Harvey Tool’s Miniature End Mill and Material Specific End Mill Sections. You can notice that while key geometries between the two tools are identical, and are in use in the same material with the same operation, the chip load (+25%), linear feed rate (+33%), and depth of cut (+43%) are boosted. This allows for more material to be removed in a shorter period of time.

Miniature End Mill

Part Number: 836408

Description: 3 Flute 1/8 inch diameter 3x LOC Square Stub & Standard

Material: 6061 Aluminum

Application: Slotting

Speed: 10,000 RPM

Chip Load: .00124 IPT

Linear Feed: 37.2 IPM

DOC: .04375

harvey tool miniature end mill

Material Specific End Mill

Part Number: 942308

Description: 3 Flute 1/8 inch diameter 3x LOC Square Variable Helix for Aluminum Alloys

Material: 6061 Aluminum

Application: Slotting

Speed: 10,000 RPM

Chip Load: .00165 IPT

Linear Feed: 49.5 IPM

DOC: .0625

harvey tool miniature variable helix end mill

Harvey Performance Company, LLC.

Extensive Cost Savings

The following chart displays a cost analysis breakdown between a tool found in the Miniature End Mill section, item 993893-C3; and a tool found in the Material Specific End Mill section, item 933293-C6. When compared for the machining of 1,000 parts, the overall savings is nearly $2,500.

material specific tooling benefit chart in cost savings

Material Specific Tooling Summarized

In conclusion, Material Specific End Mills have many benefits, but are best utilized in certain situations. While the initial cost of these tools are higher, they can work to save your shop time and money in the long run by lasting longer and producing more parts over a given period of time.

How to Extend the Life of Your End Mill

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Breaking and damaging an end mill is oftentimes an avoidable mistake that can be extremely costly for a machine shop. To save time, money, and your end mill it is important to learn some simple tips and tricks to extend tool life.

Properly Prepare Before the Tool Selection Process

The first step of any machining job is selecting the correct end mill for your material and application. However, this doesn’t mean that there should not be an adequate amount of legwork done beforehand to ensure the right decision on a tool is being made. Harvey Tool, Helical Solutions, Titan USA, and Corehog have thousands of different tools for different operations – a vast selection which, if unprepared – can easily result in selecting a tool that’s not the best for your job. To start your preparation, answer the 5 Questions to Ask Before Selecting an End Mill to help you quickly narrow down your selection and better understand the perfect tool you require.

Understand Your Tooling Requirements

It’s important to understand not only what your tool needs, but also general best practices to avoid common machining mishaps. For instance, it is important to use a tool with a length of cut only as long as needed, as the longer a tools length of cut is, the greater the chance of deflection or tool bending, which can decrease its effective life.

end mill being fed coolant cutting into a workpiece to extend tool life

Another factor to consider is the coating composition on a tool. Harvey Tool and Helical Solutions offer many varieties of tool coatings for different materials. Some coatings increase lubricity, slowing tool wear, while others increase the hardness and abrasion resistance of the tool. Not all coatings increase your tool’s life in every material, however. Be wary of coatings that don’t perform well in your part’s material – such as the use of AlTiN coating in Aluminum (Both coating and material are aluminum-based and have a high affinity for each other, which can cause built-up edge and result in chip evacuation problems).

Consider Variable Helix & Pitch Geometry

A feature on many of our high performance end mills is variable helix or variable pitch geometry, which have differently-spaced flutes. As the tool cuts, there are different time intervals between the cutting edges contacting the workpiece, rather than simultaneously on each rotation. The varying time intervals minimizes chatter by reducing harmonics, increasing tool life and producing better results.

Ensure an Effective Tool Holding Strategy

Another factor in prolonging tool life is proper tool holding. A poor tool holding strategy can cause runout, pullout, and scrapped parts. Generally, the most secure connection has more points of contact between the tool holder and tool shank. Hydraulic and Shrink Fit Tool Holders provide increased performance over other tightening methods.

three different end mills in tool holders

Helical also offers shank modifications to all stocked standards and special quotes, such as the ToughGRIP Shank, which provides added friction between the holder and the shank of the tool for a more secure grip; and the Haimer Safe-Lock™, which has grooves on the shank of the tool to help lock it into place in a tool holder.

massive helical end mill in machinists hand

Trust Your Running Parameters, and their Source

After selecting the correct end mill for your job, the next step is to run the tool at the proper speeds and feeds.

Run at the Correct Speed

Understanding the ideal speed to run your machine is key to prolonging tool life. If you run your tool too fast, it can cause suboptimal chip size, ineffective chip evacuation, or even total tool failure. Adversely, running your tool too slowly can result in deflection, bad finish, or decreased metal removal rates.

Push at the Best Feed Rate

Another critical parameter of speeds and feeds is finding the best possible feed rate for your job, for sake of both tool life and achieving maximum shop efficiency. Pushing your tool too aggressively can result in breakage, but being too conservative can lead to recutting chips and excess heat generation, accelerating tool wear.

Use Parameters from Your Tooling Manufacturer

A manufacturer’s speeds and feeds calculations take into account every tool dimension, even those not called out in a catalog and readily available to machinists. Because of this, it’s best to rely on running parameters from tooling manufacturers. Harvey Tool offers speeds and feeds charts for every one of its more than 21,000 tools featured in its catalog, helping machinists to confidently run their tool the first time.

Harvey Performance Company offers the Machining Advisor Pro application, a free, cutting-edge resource that generates custom running parameters for optimized machining with all of Helical Solutions’ and Harvey Tool’s products.

machining advisor pro graphic for pc, laptops, and other devices

Opt for the Right Milling Strategy: Climb vs Conventional

There are two ways to cut material when milling: Climb Milling and Conventional Milling. In conventional milling, the cutter rotates against the feed. In this method, chips will start at theoretical zero and increase in size. Conventional milling is usually recommended for tools with higher toughness, or for breaking through case hardened materials.

In Climb Milling, the cutter rotates with the feed. Here, the chips start at maximum width and decrease, causing the heat generated to transfer into the chip instead of being left in the tool or work piece. Climb milling also produces a cleaner shear plane, causing less rubbing, decreasing heat, and improving tool life. When climb milling, chips will be removed behind the cutter, reducing your chances of recutting.

Utilize High Efficiency Milling

High Efficiency Milling (HEM), is a roughing technique that uses the theory of chip thinning by applying a smaller radial depth of cut (RDOC) and a larger axial depth of cut (ADOC). The parameters for HEM are similar to that of finishing, but with increased speeds and feeds, allowing for higher material removal rates (MRR). HEM utilizes the full length of cut instead of just a portion of the cutter, allowing heat to be distributed across the cutting edge, maximizing tool life and productivity. This reduces the possibility of accelerated tool wear and breakage.

Decide On Coolant Usage & Delivery

Coolant can be an extremely effective way to protect your tool from premature wear and possible tool breakage. There are many different types of coolant and methods of delivery to your tool. Coolant can come in the form of compressed air, water-based, straight oil-based, soluble oil-based, synthetic or semi-synthetic. It can be delivered as mist, flood, high pressure or minimum quantity lubricant.

Appropriate coolant type and delivery vary depending on your application and tool. For example, using a high pressure coolant with miniature tooling can lead to tool breakage due to the fragile nature of extremely small tools. In applications of materials that are soft and gummy, flood coolant washes away the long stringy chips to help avoid recutting and built-up edge, preventing extra tool wear.

Extend Your Tool’s Life

The ability to maximize tool life saves you time, money and headaches. To get the best possible outcome from your tool, you first need to be sure you’re using the best tool for your job. Once you find your tool, ensure that your speeds and feeds are accurate and are from your tooling manufacturer. Nobody knows the tools better than they do. Finally, think about how to run your tool: the rotation of your cutter, whether utilizing an HEM approach is best, and how to introduce coolant to your job.

Using Tool Libraries in Autodesk HSM & Fusion 360

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The days of modeling your tools in CAM are coming to an end. Harvey Performance Company has partnered with Autodesk to provide comprehensive Harvey Tool and Helical Solutions tool libraries to Fusion 360 and Autodesk HSM users. Now, users can access 3D models of every Harvey and Helical tool with a quick download and a few simple clicks. Keep reading to learn how to download these libraries, find the tool you are looking for, how to think about speeds and feeds for these libraries, and more.

Downloading Tool Libraries

On the Autodesk HSM Tools page, you will find Harvey Tool and Helical Solutions tool libraries. Clicking either of the previous links will bring you to that brand’s tool libraries. Right now, all of the two brands more than 27,000 tools are supported in the tool libraries.

Once on the page, there will be a download option for both Fusion and HSM. Select which software you are currently using to be prompted with a download for the correct file format.

From there, you will need to import the tool libraries from your Downloads folder into Fusion 360 or HSM. These tool libraries can be imported into your “Local” or “Cloud” libraries in Fusion 360, depending on where you would like them to appear. For HSM, simply import the HSMLIB file you have downloaded as you would any other tool library.

Curt Chan, Autodesk MFG Marketing Manager, takes a deeper dive into the process behind downloading, importing, and using CAM tool libraries to Fusion in the instructional video below.

For HSM users, jump to the 2:45 mark in this video from Autodesk’s Lars Christensen, who explains how to download and import these libraries into Autodesk HSM.

Selecting a Tool

Once you have downloaded and imported your tool libraries, selecting a specific tool or group of tools can be done in several ways.

Searching by Tool Number

To search by tool number, simply enter the tool number into the search bar at the top of your tool library window. For example, if you are looking for Helical Tool EDP 00015, enter “00015” into the search bar and the results will narrow to show only that tool.

Fusion 360 Tool Libraries

In the default display settings for Fusion 360, the tool number is not displayed in the table of results, where you will find the tool name, flute count, cutter diameter, and other important information. If you would like to add the tool number to this list of available data, you can right click on the top menu bar where it says “Name” and select “Product ID” from the drop down menu. This will add the tool number (ex. 00015) to the list of information readily available to you in the table.

Harvey Tool Tool Libraries

Searching by Keyword

To search by a keyword, simply input the keyword into the search bar at the top of the tool library window. For example, if you are looking for metric tooling, you can search “metric” to filter by tools matching that keyword. This is helpful when searching for Specialty Profile tools which are not supported by the current profile filters, like the Harvey Tool Double Angle Shank Cutters seen in the example below.

Fusion 360 Tool Libraries

Searching by Tool Type

To search by tool type, click the “Type” button in the top menu of your tool library window. From there, you will be able to segment the tools by their profile. For example, if you only wanted to see Harvey Tool ball nose end mills, choose “Ball” and your tool results will filter accordingly.

CAM Tool Libraries

As more specialty profiles are added, these filters will allow you to filter by profiles such as chamfer, dovetail, drill, threadmill, and more. However, some specialty profile tools do not currently have a supported tool type. These tools show as “form tools” and are easier to find by searching by tool number or name. For example, there is not currently a profile filter for “Double Angle Shank Cutters” so you will not be able to sort by that profile. Instead, type “Double Angle Shank Cutter” into the search bar (see “Searching by Keyword”) to filter by that tool type.

Searching by Tool Dimensions

To search by tool dimensions, click the “Dimensions” button in the top menu of your tool library window. From there, you will be able to filter tools by your desired dimensions, including cutter diameter, flute count, overall length, radius, and flute length (also known as length of cut). For example, if you wanted to see Helical 3 flute end mills in a 0.5 inch diameter, you would check off the boxes next to “Diameter” and “Flute Count” and enter the values you are looking for. From there, the tool results will filter based on the selections you have made.

CAM Tool Libraries

Using Specialty Profile Tools

Due to the differences in naming conventions between manufacturers, some Harvey Tool/Helical specialty profile tools will not appear exactly as you think in Fusion 360/HSM. However, each tool does contain a description with the exact name of the tool. For example, Harvey Tool Drill/End Mills display in Fusion 360 as Spot Drills, but the description field will call them out as Drill/End Mill tools, as you can see below.

Below is a chart that will help you match up Harvey Tool/Helical tool names with the current Fusion 360 tool names.

Tool NameFusion 360 Name
Back Chamfer CutterDovetail Mill
Chamfer CuttersChamfer Mill
Corner Rounding End Mill – UnflaredRadius Mill
Dovetail CutterDovetail Mill
Drill/End MillSpot Drill
Engraving Cutter/Marking Cutter – Tip RadiusTapered Mill
Engraving Cutter – Tipped Off & PointedChamfer Mill
Keyseat CutterSlot Mill
Runner CutterTapered Mill
Undercutting End MillLollipop Mill
All Other Specialty ProfilesForm Mill

Speeds and Feeds

To ensure the best possible machining results, we have decided not to pre-populate speeds and feeds information into our tool libraries. Instead, we encourage machinists to access the speeds and feeds resources that we offer to dial accurate running parameters based on their material, application, and machine capabilities.

Harvey Tool Speeds & Feeds

To access speeds and feeds information for your Harvey Tool product, head to http://www.harveytool.com/cms/SpeedsFeeds_228.aspx to find speeds and feeds libraries for every tool.

If you are looking for tool specific speeds and feeds information, you will need to access the tool’s “Tech Info” page. You can reach these pages by clicking any of the hyperlinked tool numbers across all of our product tables. From there, simply click “Speeds & Feeds” to access the speeds and feeds PDF for that specific tool.

If you have further questions about speeds and feeds, please reach out to our Technical Support team. They can be reached Monday-Friday from 8 AM to 7 PM EST at 800-645-5609, or by email at [email protected].

Helical Solutions Speeds & Feeds

To access speeds and feeds information for your Helical Solutions end mills, we recommend using our Machining Advisor Pro application. Machining Advisor Pro (MAP) generates specialized machining parameters by pairing the unique geometries of your Helical Solutions end mill with your exact tool path, material, and machine setup. MAP is available free of charge as a web-based desktop app, or as a downloadable application on the App Store for iOS and Google Play.

machining advisor pro

To learn more about Machining Advisor Pro and get started today, visit www.machiningadvisorpro.com. If you have any questions about MAP, please reach out to us at [email protected].

If you have further questions about speeds and feeds, please reach out to our Technical Support team. They can be reached Monday-Friday from 8 AM to 7 PM EST at 866-543-5422, or by email at [email protected].

For additional questions or help using tool libraries, please send an email to [email protected]. If you would like to request a Harvey Performance Company tool library be added to your CAM package, please fill out the form here and let us know! We will be sure to notify you when your CAM package has available tool libraries.

Main Differences Between Engravers & Marking Cutters

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Understanding the Distinctions

While similar on the surface, Half-round Engraving Cutters and Marking Cutters are actually very different. Both tools are unique in the geometries they possess, the benefits they offer, and the specific purposes they’re used for. Below are the key differences that all machinists must know, as the engraving on a part is often a critical step in the machining process.

harvey tool marking cutters ad

Engravers & Marking Cutters Serve Different Purposes

All Marking Cutters are Engraving Cutters, but not all Engraving Cutters are Marking Cutters. This is because Marking Cutters are a “type” of engraving tool. By virtue of their sturdier geometry, these tools are suited for applications requiring repetition such as the engraving of serial numbers onto parts. Harvey Tool has been able to customize specific tool geometries for ferrous and non-ferrous applications, offering Marking Cutters for material specific purposes.

harvey tool marking cutter

Engraving Cutters, on the other hand, are meant for finer detailed applications that require intricate designs such as engraving a wedding band or a complex brand design.

harvey tool doubled ended engraving cutter

These Tools Have Unique Geometry Features

Historically, Engraving Cutters have been made as a half round style tool. This tool allows for a true point, which is better for fine detail, but can easily break if not run correctly. Because of this, these tools have performed well in softer materials such as aluminum and wood, especially for jobs that require an artistic engraving with fine detail.

Marking cutters are not as widely seen throughout the industry, however. These tools hold up in harder-to-machine materials exceedingly well. Marking Cutters are a form of Engraving Cutter that contain 2 flutes and a web at the tip, meaning that the tool has a stronger tip and is less susceptible to breakage.

tip details of an engraver versus marking cutter

While these tools do not contain a true point (due to their web), they do feature shear flutes for better cutting action and the ability to evacuate chips easier when compared to a half-round engraver.

Harvey Tool Product Offering

Harvey Tool offers a wide variety of both Engraving Cutters and Marking Cutters. Choose from a selection of pointed, double-ended, tip radius, and tipped-off Engraving Cutter styles in 15 included angles ranging from 10° to 120°.

types of cnc engraver tips, pointed, radiused, and tipped-off

Marking Cutters are fully stocked in tip radius or tipped-off options, and are designed specifically for either ferrous or non-ferrous materials. They are are offered in included angles from 20° to 120°.

While Engraving Cutters are offered uncoated or in AlTiN, AlTiN Nano, or Amorphous Diamond coatings, Marking Cutters are fully stocked in uncoated, AlTiN, or TiB2 coated styles.

Add Fine Details to Your Parts With Harvey Tool’s Expansive Selection of Marking Cutters

Choosing the Right Tool

While both Engraving Cutters and Marking Cutters can accomplish similar tasks, each tool has its own advantages and purpose. Selecting the correct tool is based largely on preference and applicability to the job at hand. Factors that could impact your selection would be final Depth of Cut, Width of Cut, the angle needing to be achieved, and the desired detail of the engraving.

Effective Ways to Reduce Heat Generation

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Any cutting tool application will generate heat, but knowing how to counteract it will improve the life of your tool. Heat can be good and doesn’t need to totally be avoided, but controlling heat will help prolong your tool life. Sometimes, an overheating tool or workpiece is easy to spot due to smoke or deformation. Other times, the signs are not as obvious. Taking every precaution possible to redirect heat will prolong your tool’s usable life, avoid scrapped parts, and will result in significant cost savings.

Reduce Heat Generation with HEM Tool Paths

High Efficiency Milling (HEM), is one way a machinist should explore to manage heat generation during machining. HEM is a roughing technique that uses the theory of chip thinning by applying a smaller radial depth of cut (RDOC) and a larger axial depth of cut (ADOC). HEM uses RDOC and ADOC similar to finishing operations but increases speeds and feeds, resulting in greater material removal rates (MRR). This technique is usually used for removing large amounts of material in roughing and pocketing applications. HEM utilizes the full length of cut and more effectively uses the full potential of the tool, optimizing tool life and productivity. You will need to take more radial passes on your workpiece, but using HEM will evenly spread heat across the whole cutting edge of your tool, instead of building heat along one small portion, reducing the possibility of tool failure and breakage.

heat generation in standard versus hem milling and their associated depths of cut

Chip Thinning Awareness

Chip thinning occurs when tool paths include varying radial depths of cut, and relates to chip thickness and feed per tooth. HEM is based off of the principal of chip thinning. However, if not properly executed, chip thinning can cause a lot of heat generation. When performing HEM, you effectively reduce your stepover and increase your speeds and feeds to run your machine at high rates. But if your machine isn’t capable of running high enough speeds and feeds, or you do not adjust accordingly to your reduced stepover, trouble will occur in the form of rubbing between the material and tool. Rubbing creates friction and mass amounts of heat which can cause your material to deform and your tool to overheat. Chip thinning can be good when used correctly in HEM, but if you fall below the line of reduced stepover without higher speeds and feeds, you will cause rubbing and tool failure. Because of this, it’s always important to be aware of your chips during machining.

infographic showcasing chip thinning in relation to step over

Consider Climb Milling

There are two ways to cut materials when milling: conventional milling and climb milling. The difference between the two is the relationship of the rotation of the cutter to the direction of feed. In climb milling, the cutter rotates with the feed, as opposed to conventional milling where the cutter rotates against the feed.

When conventional milling, chips start at theoretical zero and increase in size, causing rubbing and potentially work hardening. For this reason, it’s usually recommended for tools with higher toughness or for breaking through case hardened materials.

In climb milling, the chip starts at maximum width and decreases, causing the heat generated to transfer into the chip instead of the tool or workpiece. When going from max width to theoretical zero, heat will be transferred to the chip and pushed away from the workpiece, reducing the possibility of damage to the workpiece. Climb milling also produces a cleaner shear plane which will cause less tool rubbing, decreasing heat and improving tool life. When climb milling, chips are removed behind the cutter, reducing your chances of re-cutting. climb milling effectively reduces heat generated to the tool and workpiece by transferring heat into the chip, reducing rubbing and by reducing your chances of re-cutting chips.

infographic showing climb versus conventional milling in feed path and end mill direction

Utilize Proper Coolant Methods

If used properly, coolant can be an extremely effective way to keep your tool from excessive heat generation. There are many different types of coolant and different ways coolant can be delivered to your tool. Coolant can be compressed air, water-based, straight oil-based, soluble oil-based, synthetic or semi-synthetic. It can be delivered as mist, flood, high pressure or minimum quantity lubricant.

Different applications and tools require different types and delivery of coolant, as using the wrong delivery or type could lead to part or tool damage. For instance, using high pressure coolant with miniature tooling could lead to tool breakage. In materials where chip evacuation is a major pain point such as aluminum, coolant is often used to flush chips away from the workpiece, rather than for heat moderation. When cutting material that produces long, stringy chips without coolant, you run the risk of creating built-up edge from the chips evacuating improperly. Using coolant will allow those chips to slide out of your toolpath easily, avoiding the chance of re-cutting and causing tool failure. In materials like titanium that don’t transfer heat well, proper coolant usage can prevent the material from overheating. With certain materials, however, thermal shock becomes an issue. This is when coolant is delivered to a very hot material and decreases its temperature rapidly, impacting the material’s properties. Coolant can be expensive and wasteful if not necessary for the application, so it’s important to always make sure you know the proper ways to use coolant before starting a job.

Importance of Controlling Heat Generation

Heat can be a tool’s worst nightmare if you do not know how to control it. High efficiency milling will distribute heat throughout the whole tool instead of one small portion, making it less likely for your tool to overheat and fail. By keeping RDOC constant throughout your toolpath, you will decrease the chances of rubbing, a common cause of heat generation. Climb milling is the most effective way to transfer heat into the chip, as it will reduce rubbing and lessen the chance of re-chipping. This will effectively prolong tool life. Coolant is another method for keeping temperatures moderated, but should be used with caution as the type of coolant delivery and certain material properties can impact its effectiveness.

Workholding Styles & Considerations

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Machinists have a number of variables to consider when setting up devices for a machining operation. When it comes to cnc workholding, there are some major differences between holding a loosely toleranced duplicate part with a 10-minute cycle time and holding a tightly toleranced specialized part with a 10-hour cycle time. Determining which method works best for your machining job is essential to maintaining an efficient operation.

CNC Workholding Devices

Ideal workholding devices have easily repeatable setups. For this reason, some machines have standard workholding devices. Vises are generally used with milling machines while chucks or collets are used when running a lathe machine. Sometimes, a part may need a customized cnc workholding setup in order to secure the piece properly during machining. Fixtures and jigs are examples of customized devices.

Fixtures and Jigs

A jig is a work holding device that holds, supports and locates a workpiece and guides the cutting tool into a specific operation (usually through the use of one or more bushings). A fixture is essentially the same type of device, but the main difference is that it does not guide the cutting tool into a specified operation. Fixtures are typically used in milling operations while jigs are generally used in drilling, reaming, tapping and boring. Jigs and fixtures are more precise relative to standard cnc workholding devices, which leads to tighter tolerances. They can also be indexable, allowing them to control the cutting tool movement as well as workpiece movement. Both jigs and fixtures are made up of the same basic components: fixture bodies, locators, supports, and clamps.

The 4 Fixture Bodies

There are 4 basic types of fixture bodies: faceplates, baseplates, angle plates, and tombstones.

Faceplates: Typically used in lathe operations, where components are secured to the faceplate and then mounted onto the spindle.

Baseplates: Common in milling and drilling operations and are mounted to the worktable.

Angle plates: Two plates perpendicular to each other but some are adjustable or customized to change the angle of the workpiece.

Tombstones: Large vertically oriented rectangular fixtures that orients a workpiece perpendicular to the worktable. Tombstones also have two sides to accommodate multiple parts.

cnc tombstone work holding fixture body

Locators

Locators are characterized by four criteria: assembled, integral, fixed, and adjustable. Assembled locators, can be attached and removed from the fixture, which is contrary to integral locators that are built into the fixture. Fixed locators allow for no moving components, while adjustable locators permit movement through the use of threads and/or springs, and can adjust to a workpiece’s size. These can be combined to provide the appropriate rigidity-assembly convenience ratio. For example, a V-locator fixture is the combination of assembled and fixed locators. It can be secured to a fixture but has no moving components.

cnc workholding showcasing a workpiece in v-locator

Supports

Supports do exactly what their name suggests, they support the workpiece during the machining process to avoid workpiece deformation. These components can double as locators and also come fixed, adjustable and integral, or assembled. Generally, supports are placed under the workpiece during manufacturing but this also depends on the geometry of the workpiece, the machine being operated and where the cutting tool will make contact. Supports can come in different shapes and sizes. For example, rest buttons are smaller support components used in series either from underneath the workpiece or from the sides. Concurrently, parallel supports are placed on either side of the part to provide general support.

cnc material support with parallel supports and rest buttons

Clamps

Clamps are devices used for strengthening or holding things together, and come in different shapes, sizes and strengths. Vises and chucks have movable jaws and are considered standard clamps. One atypical example is the toggle clamp, which has a pivot pin that acts as a fulcrum for a lever system. One of the more convenient types is a power clamping system. There are two type of power clamping methods: hydraulic and pneumatic.

cnc workholding clamps

Example of a standard fixture setup.

Hydraulic Workholding Systems

Hydraulic Systems create a gripping force by attaining power from compressing a liquid. This type of power clamp is generally used with larger workpieces as it usually takes up less space relative to pneumatic clamps.

Pneumatic clamps

Pneumatic clamps attain their gripping force from the power created by a compressed gas (usually air). These systems are generally bulkier and are used for smaller workpieces that require less room on the worktable. Power clamping offers a few advantages over conventional clamping. First, these systems can be activated and deactivated quickly to save on changeover time. Second, they place uniform pressure on the part, which help prevent errors and deformation. A significant disadvantage they pose is the cost of a system but this can be quickly offset by production time saved.

Key Guidelines to Follow

Lastly, there are a few guidelines to follow when choosing the appropriate CNC workholding fixture or jig setup.

Ensure Proper Tolerancing

The tolerances of the workholding device being used should be 20%-50% tighter than those of the workpiece.

Utilize Acceptable Locating & Supporting Pieces

Locating and supporting pieces should be made of a hardened material to prevent wear and allow for several uses without the workpieces they support falling out of tolerance. Supports and locators should also be standardized so that they can be easily replaced.

Place Workholding Clamps in Correct Locations

Clamps should be placed above the locations of supports to allow the force of the clamp to pass into the support without deforming the workpiece. Clamps, locators and supports should also be placed to distribute cutting forces as evenly as possible throughout the part. The setup should allow for easy clamping and not require much change over time

Maximize Machining Flexibility

The design of the fixture or jigs should maximize the amount of operations that can be performed in one orientation. During the machining operation, the setup should be rigid and stable.

Bottom Line

Workholding can be accomplished in a number of different ways and accomplish the same task of successfully gripping a part during a machining operation with the end result being in tolerance. The quality of this workholding may differ greatly as some setups will be more efficient than others. For example, there is no reason to create an elaborate jig for creating a small slot down the center of a rectangular brick of aluminum; a vise grip would work just fine. Maximizing the efficiency and effectiveness of an operators’ cnc workholding setup will boost productivity by saving on changeover, time as well as cost of scrapped, out of tolerance parts.

5 Questions to Ask Before Selecting an End Mill

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Few steps in the machining process are as important as proper end mill selection. 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.

Shop Harvey Tool’s Massive Offering of Fully Stocked Miniature End Mills

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 during end mill selection 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.

graphic showcasing the tool face of end mills from 2 to 12 flutes

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.

end mill graphic with dimension callouts

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.

multiple end mills after being coated, zoomed in on cutting faces

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