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TOMI Engineering INC – Featured Customer

Since its beginning in 1977, brothers Tony and Mike Falbo have made the focal point of TOMI Engineering to deliver quality, competitively-priced parts on time. TOMI Engineering has earned a reputation through the years as being a world-class manufacturer of precision machined components and assemblies for aerospace, defense, commercial and other advanced technology industries. They are fortunate to have the highest level of engineering, quality and programming personnel on staff, and, with over 40 years in the industry, there isn’t a problem TOMI hasn’t experienced.

With all the years of experience, TOMI Engineering has a lot of knowledge to share. We had the pleasure of sitting down with Tony and Mike Falbo to ask them about their experiences, techniques, tooling and a lot more.

How was TOMI Engineering INC started?

TOMI Engineering, Inc. began in 1977 when we (Tony and Mike) teamed up and got a loan from our father to purchase our first machine.  The machine was used in the garage of our parents’ home, which still resides in Tustin, California.  Forty years, 20 current machines, and countless parts later, TOMI Engineering proudly serves the defense, airline, medical and commercial industries.  We machine just about any type of product thrown our way.  Over the years, we have made wing tips for the F16 fighter jet, enclosures for GPS housings, manifolds that help transport fluids, support frames for Gulfstream, cabin brackets for Airbus, ammunition feeders for tanks, and many, many others.

At TOMI Engineering, we aim to be a one-stop shop for our customers.  Once we receive blueprints, we can program, machine, deburr, inspect, process and assemble most parts.  We utilize a mixture of 3-and-4-axis machines in order to increase efficiency, which helps us to cut down costs to our customer.  In our temperature-controlled assembly room, we can assemble bearings, bushings, rivets, nut plates, gaskets and sealants.  We also hope to add additive machining to our repertoire soon.

What machines are you currently using in your shop?

Our 21,250 square foot facility houses 20 CNC machines.  Most of our machines are Kitamura, OKK and Okuma.  The purchase dates of these machines range from 1987 to December of 2019.  With our large machine diversity, we can machine parts smaller than a penny, and as large as 30 x 60 inches. Most of the material that makes its way through our shop is aluminum.  Whether it is 6061 or aircraft grade 7000 series, we aim to have most of our parts be aluminum.  However, we do see a large amount of 6AL-4V titanium, along with 17-4 and 15-5 steel. We are currently utilizing Mastercam 2020 for most of our programming needs and are staying up to date with software upgrades and progression.

What sets TOMI Engineering apart from the rest of the competition?

We believe our greatest asset is our experience.  Here at TOMI, we have been machining parts since 1977.  In those 40-plus years, a lot of parts have come and gone through our doors and we have helped our customers solve a large array of problems.  Most of our machinists have been with us for over 10 years, while some are approaching 20 years!  Our programmers easily boast over 60 years of experience! With so many of our employees working together for so many years, it has really helped everyone to understand what helps us quickly machine our products, while being held accountable to the high standards of AS9100. 

Where did your passion for machining start?

We grew up with machines in our garage and it wasn’t until we needed money to pay for college that our dad realized he could show us the basics of operating a milling machine, which allowed us to pay our tuition while working at home in the evenings and weekends. Machining was more of a necessity than a passion at the time. However, after nearly 40 years in the business, it has been amazing to see the strides in technology from a Bridgeport Mill to the multi-axis lights-out machining that is available today.

My favorite part of the job has always been the flexibility it has allowed me. I had the opportunity to watch my kids grow up and be a part of their lives by going to their school plays, coaching them, and being home at night to help them with anything they needed. Most importantly, I’ve had the opportunity to work with my brother, my business partner, who also shares the same ideals about being with family, so we could always cover for each while the other was gone and spending time with their family. The business would not have worked without both of us understanding the importance of each other’s input. The challenge of running a business keeps me going, and working with all of the different personalities was an added bonus.

Who is the most famous contact that you have worked on a project with? What is the most interesting product youve made?

At TOMI, we do not work with specific individuals, so we can’t really name drop.  However, a vast majority of our work is for Airbus, Boeing, or the military. So it’s pretty gratifying to say that we supply parts to some of the biggest companies in the world and that our work helps to defend this country.

The most interesting product we have made here at TOMI is a GPS housing for a defense contractor.  This part encompasses everything that we can do at TOMI: precision machining, complex/multi detail assemblies, gasket assembly, and pressure testing fluid transportation components. 

Why is high quality tool performance important to you?

High quality tool performance is important to us in many ways.  Purchasing high quality tools allow us to constantly achieve premium surface finishes, push our machines to the high speeds and feeds that they are capable of, and enjoy noticeably longer tool life.

Every part, day-in and day-out, is different.   Because of our vast array of products, our tools are always changing.  But when we are picking out Helical End Mills for Aluminum, we always go with their 3-flute variable helix cutters, and we have always been happy with them.

What sort of tolerances do you work in on a daily basis?

The tolerances we typically work with are ± tenths of an inch, as well as very tight true position cal louts. We can hold and achieve these close tolerance dimensions through our very experienced Mastercam programmers, as well as our superior quality department.  Our quality inspectors have over 30 years of experience in the industry and utilize two Zeiss Contura G2 coordinate measuring machines (CMMs).  While in their temperature controlled environment, the CMMs are capable of measuring close tolerance dimensions and are used to generate data for inspection reports.

Are you guys using High Efficiency Milling (HEM) techniques to improve cycle times? What advice do you have for others who want to try HEM?

Yes, we are using HEM techniques to improve cycle times while roughing to increase our MRR while increasing tool life. If you have CAM/CAD software that supports HEM, then go for it!  Machine Advisor Pro (MAP) is VERY helpful with the suggested speeds and feeds as a starting point.  Over time though, and through experience, we have learned that every single machine is a bit different and often needs a different approach with speeds and feeds.  Start with a smaller than suggested RDOC and physically go out to your machine and see how it sounds and what is going on.  Then, start increasing and find that sweet spot that your particular machine runs well on.  Many programmers in the industry will not take the time to go out and watch how their part is sounding and cutting on the machine and going out and doing that is the best way to really find out what you and the machine are capable of achieving.

If you could give one piece of advice to a new machinist ready to take the #PlungeIntoMachining, what would it be?

Ask questions!  Don’t be afraid to talk to programmers and fellow coworkers about what is trying to be achieved and WHY the programmer is holding tolerances a certain way.  Learn from them and watch what every cutter is doing during your cycles.  The more you learn, the more you can contribute to the machining process and move up in your business.  Sometimes it takes just one good suggestion about the machining approach that can change the set-up process from aggravating to very easy.  Lastly, be open minded to new ideas and approaches.  As we said earlier, there are a ton of ways to make good parts in a constantly evolving industry.

Please take the time to check out the TOMI Engineering INC website or follow them on social media!

Benefits & Drawbacks of High and Low Helix Angles

While many factors impact the outcome of a machining operation, one often overlooked factor is the cutting tool’s helix angle. The Helix angle of a tool is measured by the angle formed between the centerline of the tool and a straight line tangent along the cutting edge.

A higher helix angle, usually 40° or more, will wrap around the tool “faster,” while a “slower” helix angle is usually less than 40°.

When choosing a tool for a machining operation, machinists often consider the material, the tooling dimensions and the flute count. The helix angle must also be considered to contribute to efficient chip evacuation, better part finish, prolonged tool life, and reduced cycle times.

Helix Angles Rule of Thumb

One general rule of thumb is that as the helix angle increases, the length of engagement along the cutting edge will decrease. That said,
there are many benefits and drawbacks to slow and high helix angles that can impact any machining operation.

Slow Helix Tool <40°

Benefits

  • Enhanced Strength – A larger core creates a strong tool that can resist deflection, or the force that will bend a tool under pressure.
  • Reduced Lifting – A slow helix will decrease a part from lifting off of the worktable in settings that are less secure.
  • Larger Chip Evacuation – The slow helix allows the tool to create a large chip, great for hogging out material.

Drawbacks

  • Rough Finish – A slow helix end mill takes a large chip, but can sometimes struggle to evacuate the chip. This inefficiency can result in a sub-par part finish.
  • Slower Feed Rate – The increased radial force of a slow helix end mill requires running the end mill at a slower feed rate.

High Helix Tool >40°

Benefits

  • Lower Radial Force – The tool will run quieter and smoother due to better shearing action, and allow for less deflection and more stability in thin wall applications.
  • Efficient Chip Evacuation – As the helix angle increases, the length of cutting edge engagement will decrease, and the axial force will increase. This lifts chips out and away, resulting in efficient chip evacuation.
  • Improved Part Finish – With lower radial forces, high helix tools are able to cut through material much more easily with a better shearing action, leaving an improved surface finish.

Drawbacks

  • Weaker Cutting Teeth – With a higher helix, the teeth of a tool will be thinner, and therefore thinner.
  • Deflection Risk – The smaller teeth of the high helix tool will increase the risk of deflection, or the force that will bend a tool under pressure. This limits how fast you can push high helix tools.
  • Increased Risk of Tool Failure – If deflection isn’t properly managed, this can result in a poor finish quality and tool failure.

Helix Angle: An Important Decision

In summary, a machinist must consider many factors when choosing tools for each application. Among the material, the finish requirements, and acceptable run times, a machinist must also consider the helix angle of each tool being used. A slow helix end mill will allow for larger chip formation, increased tool strength and reduce lifting forces. However, it may not leave an excellent finish. A high helix end mill will allow for efficient chip evacuation and excellent part finish, but may be subject to increased deflection, which can lead to tool breakage if not properly managed.

Machining Advisor Pro Updated With New Improvements

Harvey Performance Company is excited to announce that Machining Advisor Pro, a cutting edge resource for generating custom CNC running parameters, has been updated with new features and improvements with the release of version 1.5.

Thousands of users have enjoyed the benefits of using Machining Advisor Pro (MAP) to dial in their running parameters for their Helical Solutions high-performance end mills, and with version 1.5, the Harvey Performance Company team has made customizing your speeds and feeds easier than ever. Much of the work done on MAP version 1.5 was the direct result of excellent user feedback, including some of the most innovative updates to the user experience since the launch of Machining Advisor Pro in 2018.

The new improvements to MAP include:

Improved Speed and Feed Sliders (Desktop)

The speed and feed sliders in the “Recommendations” section are now percentage-based. This allows users to more precisely adjust their running parameters while fine-tuning numbers for increased production or longer tool life. Previously, users could adjust their speed and feed values with dials, but without an exact measurement of the increase or decrease. With the new sliders, users can be more accurate, adjusting their speed and feed values by +/- 20% in one percent increments. Users can also type in percentage values to automatically adjust the sliders to their desired number.

machining advisor pro

Locking Depths of Cut

Inside of the “Parameters” section, users will now see a new button that allows them to lock their depths of cut. With this new feature, users have more control over the customization of their running parameters. In the past, the radial and axial depths of cut would adjust dynamically with each other based on the user adjustments to one of the values. Now users can lock the radial depth of cut (RDOC) and adjust the axial depth of cut (ADOC) without affecting the RDOC value, and vice versa.

Machining Advisor Pro Update

Enhanced Summary Section (Mobile)

On mobile devices, users will now see an enhanced “Summary” section at the completion of their job. The summary section will now include key metrics like material removal rate (MRR), as well as important parameters that apply to trochoidal slotting toolpaths. The summary section for chamfering toolpaths has also been updated to better reflect the necessary parameters for those tools.

Machining Advisor Pro Mobile

Smoother User Experience

In MAP version 1.5, users will be greeted with a much smoother user experience throughout the application. Due largely to user feedback, the Harvey Performance Company team has been hard at work to make sure that the major pain points within the application have been addressed. Much of the feedback centered around the “Tooling” section and the “Material” section and significant improvements have been made to each.

In the tooling section, MAP will now automatically select a tool for you if you enter a valid EDP once you navigate outside of that section. If an invalid EDP number is entered, the intrusive error message has been removed and now will display “no results found” in the drop-down menu.

In the material section, MAP requires that a material condition be selected in order to generate accurate running parameters. In the past, this was not immediately clear and could lead some users to believe that the application was malfunctioning. In version 1.5, once a user leaves the material section without selecting a condition, a message will display in the material section to alert users of the missing material condition.

Open in MAP from HelicalTool.com

On the new HelicalTool.com website, users can now import a tool into MAP from the Tool Details page. Users reach the Tool Details page by clicking on a SKU in a product table, or searching for an EDP in the search bar. Once on the Tool Details page, users can select “Open in Machining Advisor Pro” under the Resources section, and MAP will open in a new window and import the tool’s information directly into MAP.

Helical Machining Advisor Pro


Users will see these updates immediately upon their next log-in to the application on a desktop computer and will need to ensure their app is updated to the latest version from the App Store or Google Play to see these changes reflected on mobile.

To get started with Machining Advisor Pro, click here to create an account.

To stay up-to-date on all of the latest improvements and news on Machining Advisor Pro and the Harvey Performance Company brands, join our email list.

If you have any feedback or questions about MAP, please contact Harvey Performance Company at [email protected].

Simplify Your Cutting Tool Orders

With the launch of the new Helical Solutions website, Harvey Performance Company is proud to introduce a new way to order Helical cutting tools. Now, users of our new website are able to send a “shopping cart” of Helical tools they’re interested in directly to their distributor to place an order, or share it with a colleague. Let’s dive into the details about this functionality and learn how you can take advantage of the time savings associated with sending a “shopping cart” to your distributor for simplified ordering.

Get Started with a HelicalTool.com Account

First, you must create an account on HelicalTool.com. Having an account on the Helical website allows you to save and edit “shopping carts,” which can be sent to a distributor to place an order; choose a preferred distributor; auto-fill your information in any important forms; and to manage your shipping information.

Create Helical Account

 

Now that you have an account, it is time to start creating your first “shopping cart.”

Creating a “Shopping Cart”

To begin creating a new shopping cart, simply click on the “My Carts” text in the top right menu. This will take you to the management portal, where you can add a new “shopping cart” by selecting “Create New Shopping Cart.”

Helical Solutions Order

Once complete, you can name your “shopping cart” anything you would like. One example might be creating a collection of tools for each of your jobs, or for different machines in the shop. In this case, we will name it “Aluminum Roughing Job.” You can create as many different “shopping carts” as you would like; they’ll never be removed from your account unless you choose to delete them, allowing you to go back to past tooling orders whenever you’d like.

Helical Solutions Website

Now that you have a “shopping cart” created, it is time to start adding tools to it!

Adding Tools to Your “Shopping Cart”

There are multiple ways to add tooling to your “shopping cart,” but the easiest method is by heading to a product table. In this example, we will be adding tooling from our 3 Flute, Corner Radius – 35° Helix product line. We want to add a quantity of 5 of EDP #59033 to our “shopping cart.” To do this, simply click on the “Add To Cart” icon located in the table row next to pricing and tool descriptions. This will open up a small window where we can manage our selection. The first step will be to choose which “shopping cart” we want to add this tool to, so we will select our “Aluminum Roughing Job” collection.

Helical Online Ordering

Since this tool is offered uncoated and Zplus coated, we need to select which option we would like from the drop down menu. For this example, we will select the Zplus coated tool. Now, we simply need to update our quantity to “5”, and click “Add To Cart.” That tool will now appear in your “shopping cart” in the quantity selected.

If you need more information on a tool, you can click on an EDP number to be brought to the tool details page, where you can also add that EDP to your collection.

If you know the EDP number you need and want to check stock levels, use our Check Stock feature to check quantities on hand, and then add the tools to your “shopping cart” right from the Check Stock page.

check stock

Now, it is time to send the “shopping cart” to place an order with your distributor!

Placing An Order With Your Distributor

Once you have completed adding tools to your “shopping cart,” navigate back to the My Carts page to review it. From here, you can update quantities, see list pricing, and access valuable resources.

On the right side of the My Cart screen, you will see an option to “Send to Distributor.” Click on the text to expand the drop down. If you have previously added a preferred distributor from your account page and they are participating in our Shopping Cart Program, you will see their information in this area.

If you have not yet selected a preferred distributor, select “Update My Distributor.” This will bring you to a new page where you can select your state and see all participating distributors in your area. Select one distributor as your preferred distributor, and then head back to the My Cart page.

Now that you have a distributor selected, you can do a final review of the “shopping cart,” and then simply click “Send Cart.” This will send an email order directly to your distributor with all of your shipping information, your list of tools and requested quantities, and your contact information. You will also receive a copy of this email for your records.

Helical Distributor

Within 1 business day, the distributor will follow up with you to confirm the order, process payment, and get the tools shipped out and on the way to your shop. No more phone calls or emails – just a single click, and your order is in the hands of our distributor partners.

To get started with this exciting new way to shop for Helical cutting tools, click here to begin creating an account on HelicalTool.com!

Axis CNC Inc. – Featured Customer

Axis CNC Inc was founded in 2012 in Ware, Massachusetts, when Dan and Glenn Larzus, a father and son duo, decided to venture into the manufacturing industry. Axis CNC Inc has provided customers with the highest quality manufacturing, machining, and programming services since they’ve opened. They specialize in manufacturing medical equipment and have a passion for making snowmobile parts.

We sat down with Axis CNC Inc to discuss how they got started and what they have learned over there years in the manufacturing world. Watch our video below to see our full interview.

Show Us What You #MadeWithMicro100

Are you proud of the parts you #MadeWithMicro100? Show us with a video of the parts you are making, the Micro 100 Tool used, and the story behind how that part came to be, for a chance to win a $1,000 Amazon gift card grand prize!

With the recent addition of the Micro 100 brand to the Harvey Performance Company family, we want to know how you have been utilizing its expansive tooling offering. Has Micro 100’s Micro-Quik™ system helped you save time and money? Do you have a favorite tool that gets the job done for you every time? Has Micro 100 tooling saved you from a jam? We want to know! Send us a video on Instagram and show us what you #MadeWithMicro100!

How to Participate

Using #MadeWithMicro100 and @micro_100, tag your video of the Micro 100 tools machining your parts on Instagram or Facebook. Remember, don’t share anything that could get you in trouble! Proprietary parts and trade secrets should not be on display.

Official Contest Rules

Contest Dates:

  • The contest will run between December 5, 2019 to January 17, 2020. Submit as many entries as you’d like! Entries that are submitted before or after the contest period will not be considered for the top prizes (But we’d still like to see them!)

The Important Stuff:

  1. Take a video of your Micro 100 tool in action, clear and visible.
  2. Share your video on social media using #MadeWithMicro100 and tagging @Micro_100.
  3. Detail the story behind the project (tool number(s), operation, running parameters, etc.)

Prizes

All submissions will be considered for the $1,000 Amazon gift card grand prize. Of these entries, the most impressive (10) will be put up to popular vote. All entries put up to vote will be featured on our new customer testimonial page on our website with their name, social media account, and video displayed for everybody to see.

We’ll pick our favorites, but the final say is up to you. Public voting will begin on January 21, 2020, and a winner will be announced on January 28, 2020.

The top five entries will be sent Micro 100’s Micro-Quik™ tool change system with a few of our quick change tools. The top three entries will be offered a spot as a “Featured Customer” on our “In The Loupe” blog!

The Fine Print:

  • Please ensure that you have permission from both your employer and customer to post a video.
  • All entries must be the original work of the person identified in the entry.
  • No purchase necessary to enter or win. A purchase will not increase your chances of winning.
  • On January 28, 2020, the top 5 winners will be announced to the public. The Top 5 selected winners will receive a prize. The odds of being selected depend on the number of entries received. If a potential winner cannot be contacted within five (5) days after the date of first attempt, an alternative winner may be selected.
  • The potential winners will be notified via social media. Each potential winner must complete a release form granting Micro 100 full permission to publish the winner’s submitted video. If a potential winner cannot be contacted, or fails to submit the release form, the potential winner forfeits prize. Potential winners must continue to comply with all terms and conditions of these official contest rules, and winning is contingent upon fulfilling all requirements.
  • Participation in the contest constitutes entrants’ full and unconditional agreement to and acceptance of these official rules and decisions. Winning a prize is contingent upon being compliant with these official rules and fulfilling all other requirements.
  • The Micro 100 Video Contest is open to residents in US and Canada who are at least 18 years old at the time of entry.

Selecting the Right Chamfer Cutter Tip Geometry

A chamfer cutter, or a chamfer mill, can be found at any machine shop, assembly floor, or hobbyist’s garage. These cutters are simple tools that are used for chamfering or beveling any part in a wide variety of materials. There are many reasons to chamfer a part, ranging from fluid flow and safety, to part aesthetics.

Due to the diversity of needs, tooling manufacturers offer many different angles and sizes of chamfer cutters, and as well as different types of chamfer cutter tip geometries. Harvey Tool, for instance, offers 21 different angles per side, ranging from 15° to 80°, flute counts of 2 to 6, and shank diameters starting at 1/8” up to 1 inch.

After finding a tool with the exact angle they’re looking for, a customer may have to choose a certain chamfer cutter tip that would best suit their operation. Common types of chamfer cutter tips include pointed, flat end, and end cutting. The following three types of chamfer cutter tip styles, offered by Harvey Tool, each serve a unique purpose.

Three Types of Harvey Tool Chamfer Cutters

Type I: Pointed

This style of chamfer cutter is the only Harvey Tool option that comes to a sharp point. The pointed tip allows the cutter to perform in smaller grooves, slots, and holes, relative to the other two types. This style also allows for easier programming and touch-offs, since the point can be easily located. It’s due to its tip that this version of the cutter has the longest length of cut (with the tool coming to a finished point), compared to the flat end of the other types of chamfer cutters. With only a 2 flute option, this is the most straightforward version of a chamfer cutter offered by Harvey Tool.

Type II: Flat End, Non-End Cutting

Type II chamfer cutters are very similar to the type I style, but feature an end that’s ground down to a flat, non-cutting tip. This flat “tip” removes the pointed part of the chamfer, which is the weakest part of the tool. Due to this change in tool geometry, this tool is given an additional measurement for how much longer the tool would be if it came to a point. This measurement is known as “distance to theoretical sharp corner,” which helps with the programming of the tool. The advantage of the flat end of the cutter now allows for multiple flutes to exist on the tapered profile of the chamfer cutter. With more flutes, this chamfer has improved tool life and finish. The flat, non-end cutting tip flat does limit its use in narrow slots, but another advantage is a lower profile angle with better angular velocity at the tip.

Type III: Flat End, End Cutting

Type III chamfer cutters are an improved and more advanced version of the type II style. The type III boasts a flat end tip with 2 flutes meeting at the center, creating a center cutting-capable version of the type II cutter. The center cutting geometry of this cutter makes it possible to cut with its flat tip. This cutting allows the chamfer cutter to lightly cut into the top of a part to the bottom of it, rather than leave material behind when cutting a chamfer. There are many situations where blending of a tapered wall and floor is needed, and this is where these chamfer cutters shine. The tip diameter is also held to a tight tolerance, which significantly helps with programing it.

In conclusion, there could be many suitable cutters for a single job, and there are many questions you must ask prior to picking your ideal tool. Choosing the right angle comes down to making sure that the angle on the chamfer cutter matches the angle on the part. One needs to be cautious of how the angles are called out, as well. Is the angle an “included angle” or “angle per side?” Is the angle called off of the vertical or horizontal? Next, the larger the shank diameter, the stronger the chamfer and the longer the length of cut, but now, interference with walls or fixtures need to be considered. Flute count comes down to material and finish. Softer materials tend to want less flutes for better chip evacuation, while more flutes will help with finish. After addressing each of these considerations, the correct style of chamfer for your job should be abundantly clear.

How to Select a Spindle

When trying to develop efficient processes, many machinists and programmers turn to tool selection first. It is true that tooling can often make a big difference in machining time, and speeds and feeds, but did you know that your machine’s spindle can have an equally impactful effect? The legs of any CNC machine, spindles are comprised of a motor, a taper for holding tools, and a shaft that will hold all of the components together. Often powered by electricity, spindles rotate on an axis which receives its input from the machine’s CNC controller.

Why is Choosing the Right Spindle Important?

Choosing the right spindle to machine your workpiece with is of very high importance to a successful production run. As tooling options continue to grow, it is important to know what tooling your spindle can utilize. Large diameter tools such as large end mills or face mills typically require slower spindle speeds and take deeper cuts to remove vast amounts of material. These applications require supreme machine rigidity and require a spindle with high torque.

Contrastingly, smaller diameter tools will need a higher-speed spindle. Faster speeds and feeds deliver better surface finishes and are used in a variety of applications. A good rule of thumb is that an end mill that is a half inch or smaller will run well with lower torque.

Types of CNC Spindles

After finding out what you should look for in a spindle, it is time to learn about your different options. Spindles typically vary by the type, style of the taper, or its size. The taper is the conical portion of the tool holder that fits inside of the opening of the spindle. Every spindle is designed to mate with a certain taper style and size.

CAT and BT Holders

This is the most widely utilized holder for milling in the United States. Referred to as “V-flange holders,” both of these styles need a retention knob or pull stud to be secured within the machine spindle. The BT (metric style) is popular overseas.

HSK Holders

This type of holder is a German standard known as “hollow shank taper.” The tapered portion of the holder is much shorter than its counterparts. It also engages the spindle in a different way and does not require a pull stud or retention knob. The HSK holder is utilized to create repeatability and longer tool life – particularly in High Efficiency Milling (HEM) applications.

All of these holders have benefits and limitations including price, accuracy, and availability. The proper selection will depend largely on your application requirements.

Torque vs. Horsepower

Torque is defined as force perpendicular to the axis of rotation across a distance. It is important to have high torque capabilities when using an end mill larger than ½ inch, or when machining a difficult material such as Inconel. Torque will help put power behind the cutting action of the tool.

Horsepower refers to the amount of work being done. Horsepower is important for smaller diameter end mills and easy-to-machine materials like aluminum.

You can think of torque as a tractor: It can’t go very fast, but there is a lot of power behind it. Think of horsepower as a racecar: It can go very fast but cannot pull or push.

Torque-Horsepower Chart

Every machine and spindle should come with a torque horsepower chart. These charts will help you understand how to maximize your spindle for torque or horsepower, depending on what you need:

Image Source: HAAS Machine Manual

Proper Spindle Size

The size of the spindle and shank taper corresponds to the weight and length of the tools being used, as well as the material you are planning to machine. CAT40 is the most commonly used spindle in the United States. These spindles are great for utilizing tools that have a ½ inch diameter end mill or smaller in any material. If you are considering using a 1 inch end mill in a material like Inconel or Titanium, a CAT50 would be a more appropriate choice. The higher the taper angle is, the more torque the spindle is capable of.

While choosing the correct tool for your application is important, choosing a tool your spindle can utilize is paramount to machining success. Knowing the amount of torque required will help machinists save a lot of headaches.

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.

 

The Geometries and Purposes of a Slitting Saw

When a machinist needs to cut material significantly deeper than wide, a Slitting Saw is an ideal choice to get the job done. A Slitting Saw is unique due to its composition and rigidity, which allows it to hold up in a variety of both straightforward and tricky to machine materials.

What is a Slitting Saw?

A Slitting Saw is a flat (with or without a dish), circular-shaped saw that has a hole in the middle and teeth on the outer diameter. Used in conjunction with an arbor, a Slitting Saw is intended for machining purposes that require a large amount of material to be removed within a small diameter, such as slotting or cutoff applications.

Other names for Slitting Saws include (but are not limited to) Slitting Cutters, Slotting Cutters, Jewelers Saws, and Slitting Knives. Both Jewelers Saws and Slitting Knives are particular types of Slitting Saws. Jewelers Saws have a high tooth count enabling them to cut tiny, precise features, and Slitting Knives are Slitting Saws with no teeth at all. On Jewelers Saws, the tooth counts are generally much higher than other types of saws in order to make the cuts as accurate as possible.

Key Terminology

Why Use a Slitting Saw?

These saws are designed for cutting into both ferrous and non-ferrous materials, and by utilizing their unique shape and geometries, they can cut thin slot type features on parts more efficiently than any other machining tool.

Common Applications:

  1. Separating Two Pieces of Material
    1. If an application calls for cutting a piece of material, such as a rod, in half, then a slitting saw will work well to cut the pieces apart while increasing efficiency.
  2. Undercutting Applications
    1. Saws can perform undercutting applications if mounted correctly, which can eliminate the need to remount the workpiece completely.
  3. Slotting into Material
    1. Capable of creating thin slots with a significant depth of cut, Slitting Saws can be just the right tool for the job!

When Not to Use a Slitting Saw

While it may look similar to a stainless steel circular saw blade from a hardware store, a Slitting Saw should never be used with construction tools such as a table or circular saw.  Brittle saw blades such as slitting saws will shatter when used on manual machines, and can cause injury when not used on the proper set up.

In Conclusion

Slitting Saws can be beneficial to a wide variety of machining processes, and it is vital to understand their geometries and purpose before attempting to utilize them in the shop. They are a great tool to have in the shop and can assist with getting jobs done as quickly and efficiently as possible.