Tag Archive for: HEM toolpaths

Axis CNC Inc. – Featured Customer

Featured Image Courtesy of Axis CNC Inc

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.

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.

properly selecting a spindle

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:

Haas spindle horsepower and torque chart
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.

Harvey Performance Company to Participate at Autodesk University 2019

August 20, 2019 (Rowley, MA) – Harvey Performance Company, a leading provider of specialized cutting tools for precision machining applications, is excited to participate as a presenter at Autodesk University – Vegas 2019. This event will take place from November 18-21 in Las Vegas, NV at the Sands Convention Center. Autodesk University – Vegas is a four-day event which connects 10,000+ professionals from construction, manufacturing, architecture, engineering, and media creation.

Harvey Performance Company will host an instructional demo titled Boosting Shop Productivity by Applying High Efficiency Milling Techniques on Wednesday, November 20th from 9:15  – 10:15 AM PST. Scott Tiehen, Vice President of Innovation, and Don Grandt, National Application Engineer, will be on hand to host what is sure to be a great learning experience.

If you have already registered for AU Vegas 2019, you can sign-up for the Harvey Performance Company session by clicking here.

If you have not registered but are interested in learning more about this event, please visit https://www.autodesk.com/autodesk-university/conference/las-vegas/overview

Autodesk University 2019

When to and Not to Use Drop Hole Allowance

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

John Force Racing – Featured Customer

John Force Racing has been dominating the motorsports world for over 30 years, winning 20 championships and hundreds of races in the National Hot Rod Association (NHRA) drag racing series. John Force Racing features both Funny Car and Top Fuel teams, and just recently in 2017 they won both the Funny Car and Top Fuel championships in the same season.

John Force Racing invested in Force American Made to develop and create parts and components that would help drive all the teams to success and safety. The 84,000 square foot shop is located in Brownsburg, Indiana (just outside of Indianapolis) and is the heartbeat of John Force Racing. Thousands of parts are forged by Force American Made and its team of employees every season giving the team a competitive edge that has led to the team’s on-track success.

The Force American Made team has relied on Helical Solutions tooling to get the best performance and quality out of their CNC mills for years. The Harvey Performance Company team was invited out to Indiana to take a tour of Force American Made and spend some time with Tom Warga, Lead Machinist, to talk with him about his experiences with Helical Solutions tooling, his first time trying Machining Advisor Pro, the success they have had using the new Helical tool libraries for Mastercam, and the value their distributor, Dolen Tool, brings to the shop. Check out the video interview below to see the inner-workings of Force American Made and how Helical Solutions tooling has contributed to the success of this motorsports dynasty.

Chipbreaker vs. Knuckle Rougher End Mills

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.

Nueva Precision – Featured Customer

Featured Image Courtesy of Nueva Precision

When it comes to CNC manufacturing services and product development solutions in the Denver, Colorado area, Eddie Casanueva has quickly made a name for himself with his company, Nueva Precision. Eddie has more than 22 years of manufacturing experience and 19 years of business experience, which he uses to help small businesses and entrepreneurs who are looking for product support and development.

Eddie was able to take time out of his busy schedule to talk with us for this Featured Customer post. We covered topics like Eddie’s incredible training and introduction to manufacturing, his experiences using reduced neck end mills, and his suggestions for must-have equipment in any CNC machine shop.

Thanks for taking the time to talk to us for this Featured Customer post. To get started, tell us a little bit about the history behind Nueva Precision and what sort of products you typically manufacture.

Nueva Precision was first incorporated at the end of 2016. Within three months, I was making chips on my own, largely doing prototype work.

I had recently sold my share in another company I co-founded and used that money to move into a larger home in the Denver area that could accommodate a machine shop business. We were lucky enough to find a home with some acreage and an existing oversized garage which was perfect for a shop. Now that I had the building, I had to do things like get the electrical and HVAC up to spec. It required having the city run a stronger electrical line to the building I would use as my shop, but once that was all figured out, we were ready to make some chips.

Nueva Precision

Photo Courtesy of: Nueva Precision

I started by buying a used Haas mill and a used Haas lathe. People initially reached out to me for work because of my quick delivery times. I was able to turn around parts in just a week or two since the business was new. However, within a month of operating those machines, I was already at max capacity with my current equipment. Unfortunately, my lead times had increased to a more standard 4-6 weeks due to the sheer amount of work I was getting. For the rest of 2017, I stuck with my original equipment and just did the best I could to keep up.

nueva precision

Photo Courtesy of: Nueva Precision

Do you have any future plans to expand your shop and capabilities further?

I do! In early 2018 I brought in a brand new VM3 Haas Mill to keep up with demand, but I was curious about how much more revenue that would create. I expected to see a 20-30% increase in revenue, but having another machine ended up doubling my revenue. Luckily my strong relationships with my customers helped me grow the business even as my lead times increased. With that in mind, I just ordered another Haas VM2 at the end of 2018 and am excited to take full advantage of that.

How has your family reacted to you running a business out of your home?

My family has been extremely supportive throughout the whole process. My wife Leandra in particular helps out a lot. She was a teacher for 19 years, but resigned from that profession to work on Nueva Precision. She has started to help out on the business side of things and has also started to help run machines and make parts. My oldest son Jaden (16) is interested in manufacturing and he has started working and making simple parts for us when he is available. All in all, we have a pretty good thing going here.

Eddie and Leandra Nueva Precision

Eddie and Leandra Photo Courtesy of: Nueva Precision

Jaden nueva precision

Jaden working on parts Photo Courtesy of: Nueva Precision

How did you first get involved in CNC machining and advanced manufacturing?

I am essentially self-taught in CNC machining. I got started in engineering and manufacturing as a student at the New Jersey Institute of Technology (NJIT) in the Mechanical Engineering program. It was a state school, so tuition costs weren’t bad but I still needed to support myself. I was going to school during the day and pumping gas at night to pay the bills. In my second year in school I came across an opportunity to work at an on-campus research center for manufacturing systems. It was funded by the state of New Jersey to help promote New Jersey industry. The job didn’t have much to do with my curriculum, but they supported some campus research and worked closely with the college on various projects.

The research center had all the workings of a machine shop. 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 of all the machinists and try to do more and more than the usual student employee. John – a talented toolmaker and experienced 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. Next thing I know, they’re handing me prints and I am making parts. A few months down the road the machinists started teaching me programming on a Mazak controller. This went on for a year or so and I just soaked it all in.

nueva precision

Photo Courtesy of: Nueva Precision

Sounds like great experience! Where did you land your first full-time position in manufacturing?

I actually landed my first full-time job at the same manufacturing research center. The center had a CNC machinist programmer resign at the facility, so there was a job opening posted. I went to the director of the center and said I was interested in the position. I knew I had to work a lot to pay my tuition, and if I worked for the university I could get my tuition paid for while also making some real money. The director recommended me for the position, so I interviewed and landed the job. All of a sudden, I had benefits, vacation, real responsibilities, and full-time pay. I flipped my schedule around so I could go to school during nights and work during the day.

I learned so much about machining in my first job because of the unique situation I was in. Companies like Blaser Swisslube, Kennametal, and GibbsCAM were supplying us with product and support to work on process improvements for large New Jersey corporations like BF Goodrich Aerospace, US Can, etc. It progressed to the point where GibbsCAM was actually sending me to seminars to train me on different industry topics to further my education and improve the reports we were outputting.

nueva precision

Photo Courtesy of: Nueva Precision

I was in an amazing position to get all this training and I learned so much in the next 4-5 years. We had equipment like a Fadal 5-Axis CNC Machine and other high tech machines at my disposal, which were very hard to find at the time (mid-1990s). Nobody outside of the most elite machine shops were working in 5-axis, so I had a head start because of this unique job experience.

I actually never finished my degree and instead dove head first into manufacturing. I started my own business on the side and kept working at the research center until 2001 when I left to focus full-time on my new business, Spidertrax Offroad.

Can you tell us more about your experience with Spidertrax Offroad?

Spidertrax Offroad is a manufacturer of drivetrain parts for off-roading vehicles. I started Spidertrax with a partner whom I met in college. The company actually started making our first parts at the research center I was employed at. I asked my boss if I could start making parts off the clock on my own time, and he agreed to let me use the shop. This would have been around 1998, and by 2001 I was ready to take off on my own. My partner and I built that company up to 20 employees, and we were (and they still are) a well-respected brand in the off-roading community.

The hardest part about operating my own business and watching it grow was losing the ability to get out in the shop and actually do what I love, which is making parts. As the business grew, I had to take on more responsibility as a “business man,” and let go of many of the things I enjoyed doing as a machinist. I was very proud of what we had built, but I really wanted to get back to basics. So, in early 2017 I sold my half of Spidertrax Offroad to my partner and took that money to buy the new house and open Nueva Precision, Inc.

What sort of machines and CAM software do you have in your new shop?

Right now for CNC machines I have a 2018 Haas VM3, a 2018 Hass VM2, a 2012 Haas VF2, and a 2012 Haas TL2. I also have an engine lathe, a Bridgeport knee mill, Kaeser screw compressor, which I absolutely love, and a couple of Jet saws.

For software, I still use GibbsCAM. I have been using GibbsCAM since 1996 and have had countless hours of training and experience using it, so I think I’m a lifer.

haas vf2

Photo Courtesy of: Nueva Precision

Outside of tooling, what are some key components of your machining setup that you would recommend to others?

I started Nueva Precision without any sort of probing system in place, and using an umbrella style tool changer. I found out quickly that my time, especially being alone, is worth a lot. I highly recommend getting a solid probing system as well as a side mount tool changer. I added all of that to my VM3 and the effect was immediately noticeable. It is so much more efficient and faster.

Keeping software up-to-date is also key. It can be expensive, but it speaks for itself in just a few months. Any time I invest in technology, it seems to pay off pretty quick.

5th axis workholding

Photo Courtesy of: Nueva Precision

I also feel strongly about having solid workholding. I have a couple of the 5th Axis self-centering vises which are great, and a handful of Kurt vises, as well. I am also a big fan of the MMM-USA guys and their vise jaws and handles. For my shop, flexibility is key because I never know what can come through the door. I don’t do a lot of production work and spend much more time on prototype work, so flexibility is key. Having good quality workholding that I don’t need to worry about lets me swap parts in and out with ease.

As for tool holding, I ran into an issue last year where I was starting to see a lot of tool pullout and was scrapping too many parts as a result of aggressive roughing. I had to find a better solution, and I came across the REGO-FIX PowRgrip system. It might seem expensive compared to other simpler tool holder, but I think the upfront investment isn’t too bad considering the other options in that space. Again, I invested in technology, and immediately saw better results. I currently use the PowRgrip for finishing passes where I need good runout and heavy roughing where there is the highest risk of tool pullout.

REGO powRgrip

Photo Courtesy of: Nueva Precision

You use a lot of Helical’s Reduced Neck end mills. What are some tips or tricks you have learned by using these tools that you could share with others?

My experience with these tools is really new, but I find myself using more and more of them these days. In the beginning, I was afraid of end mills with a longer length of cut singing like crazy in the machine. I started experimenting with the reduced neck tools from Helical and was blown away by the rigidity. The tool pressure remains consistent throughout the part, so you will get the same great results on the top of the part as on the bottom.

I don’t know how many people are currently using them but it makes so much stuff possible. I have gone as large as ¾” diameter with the 5” reach and have never had an issue. Maintaining the low levels of runout is definitely key with these tools, which again comes back to having solid toolholding. Now that I have the REGO-FIX system, I am getting much better runout and plan to start pushing the reduced neck tools even harder.

helical reduced neck end mill

Photo Courtesy of: Nueva Precision

Most of my reduced neck end mills are the standard style, but the chipbreaker with the reduced neck has been a powerhouse for me as well. No matter what I tried with Helical’s reduced neck tooling, I have had success, so I would recommend the entire line if the situation calls for it. Just be careful with runout and make sure to double check your clearance!

What are some of your key Helical products that you use on a daily basis?

My main workhorse is Helical EDP 29422 – the ½” 45 Degree Chipbreaker for Aluminum. I swear I use that tool every single day across all of my machines. That tool is gold for me; it is night and day compared to standard roughers. It has a long enough flute length to be versatile or aggressive, depending on the situation. It is just a great tool. You will need a good holder for sure to keep it from pulling out when you get aggressive, but again my new software and tool holding helps with that.

helical solutions

Photo Courtesy of: Nueva Precision

Outside of performance, I love getting the smaller chips that the chipbreaker tools create. It is so much easier to clean a machine with small chips than long, stringy ones, which saves me time. I do all my roughing with chipbreakers. If you are making stringy chips while running HEM toolpaths, they can be a major pain to deal with.

My customers love the finish that Helical gives me as well. The wiper flat on the bottom of the H40ALV-3 end mill stands out as one of my favorite features on any of my tools. That tool gets me compliments on the floor finishes of pockets and enclosures all the time. Across the board, tool life and finish has been awesome with my Helical end mills. I currently use the Zplus coating for all my aluminum tools and have no complaints.

part finish

Photo Courtesy of: Nueva Precision

This summer I had the privilege of working on some aerospace parts that will be going up into space!  Most all parts were being machined from pre-hardened stainless steels and exotic alloys.  The Helical 5-flute and 7-flute endmills with the Aplus coating proved to be great tools to have in the arsenal.

What are your “go-to” Harvey Tool products?

For Harvey Tool, I use a lot of the full radius Keyseat Cutters to surface mill areas you can’t get to with a ball nose end mill. This saves me valuable time because I can avoid flipping the part to surface mill both sides by doing it all in one operation with the Keyseat Cutter.

keyseat cutter

Photo Courtesy of: Nueva Precision

Outside of the keyseats, I use a lot of miniature end mills with reduced shanks and chamfers mills in a variety of angles. I also use lollipops (undercutting end mills) to surface mill parts with hard-to-reach holes.

Overall, being able to look through a single catalog and find tons of options for neck diameters and cutter diameters is what sells me on the Harvey Tool product. It is really neat to have all those different tools available to me in one place – it’s a great catalog.


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

Effective Ways to Reduce Heat Generation

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

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.