## How Boring Bar Geometries Impact Cutting Operations

Boring is a turning operation that allows a machinist to make a pre-existing hole bigger through multiple iterations of internal boring. It has a number of advantages over traditional drilling methods:

• The ability to cost-effectively produce a hole outside standard drill sizes
• The creation of more precise holes, and therefore tighter tolerances
• A greater finish quality
• The opportunity to create multiple dimensions within the bore itself

Solid carbide boring bars, such as those offered by Micro 100,  have a few standard dimensions that give the tool basic functionality in removing material from an internal bore. These include:

Minimum Bore Diameter (D1): The minimum diameter of a hole for the cutting end of the tool to completely fit inside without making contact at opposing sides

Maximum Bore Depth (L2): Maximum depth that the tool can reach inside a hole without contact from the shank portion

Shank Diameter (D2): Diameter of the portion of the tool in contact with the tool holder

Overall Length (L1): Total length of the tool

Centerline Offset (F): The distance between a tool’s tip and the shank’s centerline axis

## Tool Selection

In order to minimize tool deflection and therefore risk of tool failure, it is important to choose a tool with a max bore depth that is only slightly larger than the length it is intended to cut. It is also beneficial to maximize the boring bar and shank diameter as this will increase the rigidity of the tool. This must be balanced with leaving enough room for chips to evacuate. This balance ultimately comes down to the material being bored. A harder material with a lower feed rate and depths of cut may not need as much space for chips to evacuate, but may require a larger and more rigid tool. Conversely, a softer material with more aggressive running parameters will need more room for chip evacuation, but may not require as rigid of a tool.

## Geometries

In addition, they have a number of different geometric features in order to adequately handle the three types of forces acting upon the tool during this machining process. During a standard boring operation, the greatest of these forces is tangential, followed by feed (sometimes called axial), and finally radial. Tangential force acts perpendicular to the rake surface and pushes the tool away from the centerline. Feed force does not cause deflection, but pushes back on the tool and acts parallel to the centerline. Radial force pushes the tool towards the center of the bore.

### Defining the Geometric Features of Boring Bars:

Nose Radius: the roundness of a tool’s cutting point

Side Clearance (Radial Clearance): The angle measuring the tilt of the nose relative to the axis parallel to the centerline of the tool

End Clearance (Axial Clearance): The angle measuring the tilt of the end face relative to the axis running perpendicular to the centerline of the tool

Side Rake Angle: The angle measuring the sideways tilt of the side face of the tool

Back Rake Angle: The angle measuring the degree to which the back face is tilted in relation to the centerline of the workpiece

Side Relief Angle: The angle measuring how far the bottom face is tilted away from the workpiece

End Relief Angle: The angle measuring the tilt of the end face relative to the line running perpendicular to the center axis of the tool

### Effects of Geometric Features on Cutting Operations:

Nose Radius: A large nose radius makes more contact with the workpiece, extending the life of the tool and the cutting edge as well as leaving a better finish. However, too large of a radius will lead to chatter as the tool is more exposed to tangential and radial cutting forces.

Another way this feature affects the cutting action is in determining how much of the cutting edge is struck by tangential force. The magnitude of this effect is largely dependent on the feed and depth of cut. Different combinations of depth of cuts and nose angles will result in either shorter or longer lengths of the cutting edge being exposed to the tangential force. The overall effect being the degree of edge wear. If only a small portion of the cutting edge is exposed to a large force it would be worn down faster than if a longer portion of the edge is succumb to the same force. This phenomenon also occurs with the increase and decrease of the end cutting edge angle.

End Cutting Edge Angle: The main purpose of the end cutting angle is for clearance when cutting in the positive Z direction (moving into the hole). This clearance allows the nose radius to be the main point of contact between the tool and the workpiece. Increasing the end cutting edge angle in the positive direction decreases the strength of the tip, but also decreases feed force. This is another situation where balance of tip strength and cutting force reduction must be found. It is also important to note that the angle may need to be changed depending on the type of boring one is performing.

Side Rake Angle: The nose angle is one geometric dimension that determines how much of the cutting edge is hit by tangential force but the side rake angle determines how much that force is redistributed into radial force. A positive rake angle means a lower tangential cutting force as allows for a greater amount of shearing action. However, this angle cannot be too great as it compromises cutting edge integrity by leaving less material for the nose angle and side relief angle.

Back Rake Angle: Sometimes called the top rake angle, the back rake angle for solid carbide boring bars is ground to help control the flow of chips cut on the end portion of the tool. This feature cannot have too sharp of a positive angle as it decreases the tools strength.

Side and End Relief Angles: Like the end cutting edge angle, the main purpose of the side and end relief angles are to provide clearance so that the tools non-cutting portion doesn’t rub against the workpiece. If the angles are too small then there is a risk of abrasion between the tool and the workpiece. This friction leads to increased tool wear, vibration and poor surface finish. The angle measurements will generally be between 0° and 20°.

## Boring Bar Geometries Summarized

Boring bars have a few overall dimensions that allow for the boring of a hole without running the tool holder into the workpiece, or breaking the tool instantly upon contact. Solid carbide boring bars have a variety of angles that are combined differently to distribute the 3 types of cutting forces in order to take full advantage of the tool. Maximizing tool performance requires the combination of choosing the right tool along with the appropriate feed rate, depth of cut and RPM. These factors are dependent on the size of the hole, amount of material that needs to be removed, and mechanical properties of the workpiece.

## Using Tool Libraries in Autodesk HSM & Fusion 360

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.

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.

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.

### 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.

### 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.

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.

## 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 Name Fusion 360 Name Back Chamfer Cutter Dovetail Mill Chamfer Cutters Chamfer Mill Corner Rounding End Mill – Unflared Radius Mill Dovetail Cutter Dovetail Mill Drill/End Mill Spot Drill Engraving Cutter/Marking Cutter – Tip Radius Tapered Mill Engraving Cutter – Tipped Off & Pointed Chamfer Mill Keyseat Cutter Slot Mill Runner Cutter Tapered Mill Undercutting End Mill Lollipop Mill All Other Specialty Profiles Form 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.

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.

## Fleet Machine Co. – Featured Customer

Fleet Machine Co. was founded in 2010 to dramatically outperform other contract manufacturers by fusing advanced machine tools, automation and custom software to achieve what they call “Zero Manufacturing”. The team at Fleet Machine take pride in their ability to produce zero defects, zero missed delivery dates, carry zero part and material inventory, and maintain zero process inefficiencies. Every strategic decision and investment that they make is based on this philosophy of eliminating waste and human error from the manufacturing process.

For Manufacturing Day 2018, the team at Fleet Machine hosted several shop tours for Harvey Performance Company employees. Employees across all departments from Customer Service and Marketing to Finance and Accounting were given a in-depth tour of Fleet Machine’s manufacturing process. Josh Pregent, co-owner of Fleet Machine, was kind enough to host the tours at his shop and talk to us for this post. We talked with Josh about manufacturing automation, the challenges of obtaining AS9100/ISO9001 certification for your business, and the advantages of different milling machine types.

## Thanks for hosting our team at your shop. It was a great tour! To get started, tell us a little bit about Fleet Machine’s history, and what sort of products you typically manufacture.

Fleet Machine Co. was incorporated in 2010 in Gloucester, MA to manufacture precision components for the Aerospace, Defense, Medical, and Robotics industries. Fleet’s emphasis on quality, customer service, and professionalism quickly distinguished us from other manufacturers and allowed us to outgrow our original location and expand to our current location. Since our inception, we have devoted our company to automating manufacturing and business processes to minimize human interaction and error in the manufacturing process. Our ultimate goal is to completely eliminate all human involvement in production. This may seem like a lofty goal, but you have to have dreams!

## How did you first get involved in manufacturing?

My business partner and I both worked in a machine shop while we were in college and instantly became interested in manufacturing. Over the years, we advanced through the different facets of manufacturing, learning everything we could. In 2010 we seized an opportunity and decided to branch out on our own to start Fleet Machine.

## Do you have any advice for someone who is looking to open their own shop?

Opening your own shop involves more than knowing 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.

## We saw a good mix of machine types while walking around the shop floor. What sort of machines and software do you have here in the shop?

Fleet currently has three two axis turning centers, four three axis VMCs (Vertical Milling), one mill/turn with sub-spindle, and two HMCs (horizontal milling) with sixteen work stations each. It is a long list, but the specific types of machines we have in our facility are listed below. For software, we use a custom Salesforce CRM module, E2 MRP, and Mastercam 2019 for programming.

### CNC MILLING

• (2) Akari-Seiki 450i HMC 27 x 26 x 25 X, Y, Z Travel, dual 400mm pallets, 15,000 RPM, through spindle coolant, 80 tools
• (2) Mori-Seiki MV-40E VMC 22 x 16 x 18” X, Y, Z Travel, 20 tools, 8000 RPM
• (1) Mori-Seiki MV-40B VMC 31 x 16 x 20” X, Y, Z Travel, 20 tools, 8000 RPM
• (1) Haas VF-2 VMC 30 x 16 x 20” X, Y, Z Travel, 25 tools, 10,000 RPM

### CNC TURNING

• (1) Mori-Seiki SL-15 5000 RPM, 9” maximum turning diameter x 16” maximum length
• (1) Yama-Seiki GA-2000 6000 RPM, 13” maximum turning diameter x 20” maximum length, programmable tailstock, tool setter
• (1) Doosan Puma 240MSB 6000 RPM, 11” maximum turning diameter, 18” maximum length, dual spindle, live tooling, C-axis milling, tool setter, part catcher/part conveyor
• (1) Mori-Seiki CL-200 4000 RPM, 11” Maximum turning diameter, 12” maximum length

## How has the mill/turn CNC machine helped you speed up production? Would you recommend it to others?

Our mill/turn machine has helped us increase production by reducing our setup time. There is no longer a need to remove a turned part, get it over to a mill, and set everything up again. Most basic milling operations can be performed on the mill/turn machine, so it is a great time saver.

We would definitely recommend this type of machine to other shops. Ultimately, we highly recommend any machine/software/process/ancillary equipment that eliminates or reduces human labor. Manufacturing is a ruthlessly competitive, tech-driven industry and the failure to invest in technology of this type exposes you to over reliance on expensive, scarce, and potentially unreliable human labor and possible obsolescence.

## You also have both horizontal milling centers (HMCs) and vertical milling centers (VMCs). What has been your experience with both, and do you prefer one style over the other?

In my opinion, HMCs are superior to VMCs in every respect due to the additional axis, superior chip evacuation, greater load capacity, and the ability to run unattended with pallet pools. VMCs are still useful for simple jobs and rapid prototyping, but for high production runs we lean on the HMCs to get the job done.

## What have been some of your keys to success for expanding the business and growing your shop to take on more work?

Fleet Machine provides a superior product in terms of quality and value and uses automation and poke yoke techniques to streamline processes and eliminate the possibility of error.

## We noticed the banner hanging in the shop celebrating your AS9100/ISO9001 certification. How important has that been in your manufacturing process?

Having an AS9100/ISO9001-certified quality system will improve every aspect of your organization while eliminating waste, improving product quality, and improving OTD. Imposing the discipline required to attain certification on your company will reveal inefficiencies that you never realized existed.

## Do you have any advice for shops looking to try and get their AS9100/ISO9001 certification?

It is easily worth the investment but it requires attention to detail, extensive documentation, focus on constant improvement, and a real commitment from all employees. It needs to govern every aspect of your business, from the quoting process to shipping. If you don’t have someone who is extremely organized and enjoys data collection, measurement, and documentation, or employees who aren’t compliant or don’t understand the value of certification, it probably isn’t for you.

## Who are some of your key customers?

Some of our key customers (the ones we can name) include Hill-Rom, United Technologies Corp, Rockwell, and B/E Aerospace. We do work under NDAs for some projects so we cannot reveal all of our customers, but they are heavily skewed to the Aerospace, Medical, Robotics, and Defense industries.

## How do Harvey Tool products help Fleet Machine stay at the top of their game?

Harvey Tool products are an integral part of what we do, from the quoting process through finishing. Fleet relies on the tooling engineers and technical support team at Harvey to help us produce parts that we wouldn’t otherwise be able to make.

## What skills or qualities do you look for when hiring a new machinist?

Fleet Machine has a robust training program for all new employees. We look for important soft skills such as good written and verbal communication, reliability, a positive attitude, the ability to work as part of team, and basic computer skills. We have found that people with this combination of attributes rapidly surpass people with machining skills who lack these qualities.

Being well-rounded is important as an employee in any business, but as manufacturing progresses to become more and more technology-based it will be important to hire machinists with computer skills and technological know-how to stay ahead of your competitors.

Would you like to be considered for a future “Featured Customer” blog? Click here to submit your information.

## 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.

## What is Contouring?

Contouring a part means creating a fine finish on an irregular or uneven surface. Dissimilar to finishing a flat or even part, contouring involves the finishing of a rounded, curved, or otherwise uniquely shaped part.

## Contouring & 5-Axis Machining

5-axis machines are particularly suitable for contouring applications. Because contouring involves the finishing of an intricate or unique part, the multiple axes of movement in play with 5-axis Machining allow for the tool to access tough-to-reach areas, as well as follow intricate tool paths.

Advanced CAM software can now write the G-Code (the step-by-step program needed to create a finished part) for a machinists application, which has drastically simplified contouring applications. Simply, rather than spend several hours writing the code for an application, the software now handles this step. Despite these advances, most young machinists are still required to write their own G-Codes early on in their careers to gain valuable familiarity with the machines and their abilities. CAM software, for many, is a luxury earned with time.

#### Benefits of Advanced CAM Software

1. Increased Time Savings
Because contouring requires very specific tooling movements and rapidly changing cutting parameters, ridding machinists of the burden of writing their own complex code can save valuable prep time and reduce machining downtime.

2. Reduced Cycle Times
Generated G-Codes can cut several minutes off of a cycle time by removing redundancies within the application. Rather than contouring an area of the part that does not require it, or has been machined already, the CAM Software locates the very specific areas that require machining time and attention to maximize efficiency.

3. Improved Consistency
CAM Programs that are packaged with CAD Software such as SolidWorks are typically the best in terms of consistency and ability to handle complex designs. While the CAD Software helps a machinist generate the part, the CAM Program tells a machine how to make it.

## Contouring Tips

#### Utilize Proper Cut Depths

Prior to running a contouring operation, an initial roughing cut is taken to remove material in steps on the Z-axis so to leave a limited amount of material for the final contouring pass. In this step, it’s pivotal to leave the right amount of material for contouring — too much material for the contouring pass can result in poor surface finish or a damaged part or tool, while too little material can lead to prolonged cycle time, decreased productivity and a sub par end result.

The contouring application should remove from .010″ to 25% of the tool’s cutter diameter. During contouring, it’s possible for the feeds to decrease while speeds increases, leading to a much smoother finish. It is also important to keep in mind that throughout the finishing cut, the amount of engagement between the tool’s cutting edge and the part will vary regularly – even within a single pass.

#### Use Best Suited Tooling

Ideal tool selection for contouring operations begins by choosing the proper profile of the tool. A large radius or ball profile is very often used for this operation because it does not leave as much evidence of a tool path. Rather, they effectively smooth the material along the face of the part. Undercutting End Mills, also known as lollipop cutters, have spherical ball profiles that make them excellent choices for contouring applications. Harvey Tool’s 300° Reduced Shank Undercutting End Mill, for example, features a high flute count to benefit part finish for light cut depths, while maintaining the ability to reach tough areas of the front or back side of a part.

#### Fact-Check G-Code

While advanced CAM Software will create the G-Code for an application, saving a machinist valuable time and money, accuracy of this code is still vitally important to the overall outcome of the final product. Machinists must look for issues such as wrong tool call out, rapids that come too close to the material, or even offsets that need correcting. Failure to look G-Code over prior to beginning machining can result in catastrophic machine failure and hundreds of thousands of dollars worth of damage.

Inserting an M01 – or a notation to the machine in the G-Code to stop and await machinist approval before moving on to the next step – can help a machinist to ensure that everything is approved with a next phase of an operation, or if any redundancy is set to occur, prior to continuation.

## Contouring Summarized

Contouring is most often used in 5-axis machines as a finishing operation for uniquely shaped or intricate parts. After an initial roughing pass, the contouring operation – done most often with Undercutting End Mills or Ball End Mills, removes anywhere from .010″ to 25% of the cutter diameter in material from the part to ensure proper part specifications are met and a fine finish is achieved. During contouring, cut only at recommended depths, ensure that G-Code is correct, and use tooling best suited for this operation.

## Helical Solutions Engineers Featured in Strausak Video

Helical Solutions Director of Engineering Brian McKahan and Senior Manufacturing Engineer Forrest Thurston were featured in an April 2, 2017 Strausak video entitled “Stäubli robots at Strausak, to improve machine autonomy,” in which Helical’s use of this robot arm and its production benefits are discussed.

“We just picked up the Strausak machine in October specifically for our specialty form tools.” Thurston said in the video.

“I will have all of our carbide blanks in pallets, and once the job is set up, the robot will pick up the blank and it will put it in the machine in the holder. And when the tool is finished, it will place the finished tool in a different pallet and load the next part completely unattended.”

Due in large part to the Stäubli Robots and their ability to help maximize machine potential, production levels at Helical have grown tremendously since 2016.

“As anybody knows in the manufacturing industry, the floor space is critical,” McKahan said. “You want the smallest footprint you can get and the maximum value from the machine.”

View the Video