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Octane Workholding – Featured Customer

Located in Danville, Pennsylvania, Octane Workholding has a long history spanning back to 40 years. This family business started in the 1980s, welding farm equipment and doing general repairs. As time went on, Octane Workholding began shifting toward building bespoke equipment. As the equipment became more complex, machining became a larger part of their business, starting with manual machines and working towards CNC machining. They started to realize the amount of knowledge that they would need to learn to master CNC machining. After machining thousands of parts and gaining experience, they learned what tools were needed to succeed as Machinists and started their journey. They developed value-added products for their own use that are now available for everyone and provide educational materials that are aimed at lessening the steep learning curve of this trade.

Octane Workholding has dedicated years to mastering their CNC abilities. We were able to get in touch with Derek Pulsifer, President of Octane Workholding, to discuss how they got started, current business, and so much more!

How did you get started with Octane Workholding?

Basically, I grew up in our family shop but did not start working full time until after college. Things were heavily fabrication-oriented with only a few manual machines. After a few years running manuals myself, it was decided we would go the CNC route. Teaching myself to be a Machinist was often a struggle with no formal training or peers to reference. Being a family machine shop and working alongside Octane Sr., it could be a lot like an episode of Orange County Choppers. Most of what I share today was learned through thousands of hours of researching and learning the hard way. 

How did you get from welding farm equipment and doing repairs, to manufacturing workholding setups?

Like many things in life, things progressed and customers’ needs shifted. Our fabrication shop has built a lot of equipment for the food, pharmaceutical, and power generation industries for several years. As we gained more customers, things slowly shifted toward more job shop-oriented work. Jobshop work is a surefire way to gain experience quickly. As a Machinist, there were many times I went in search of a solution for common problems we faced. After finding solutions that didn’t fit us, I designed the products we now make today. Thousands of unique parts and decades of experience later, we knew what shops like us were probably encountering as well. Octane Workholding was created to provide solutions to common machining problems. We continue to offer quote-based work to customers through our machine shop in addition to Octane Workholding. We are Craftsmen.

What machines do you currently have in your shop?

We have several manual machines from the classic 1960’s Bridgeport to heavy-duty Cat50 verticals. The machine I actually began on is an old South Bend lathe. Production sawing, Roll Grooving, Shears, Press Brakes, Waterjet Cutting, Welding, and Rolling machines. We also have various new CNC machinery from lathes to verticals. 

What CAM/CAD softwares do you currently use?

I program with both Mastercam and Solidworks. We use Autocad products for 2D applications like Waterjet Cutting. The advent of Fusion 360 has really benefited the industry by bringing affordable software to everyone. I would like to experiment with more CAD/CAM systems to help those who come to us with specific programming questions related to Fusion 360 etc.

What materials are you most often working with?

We primarily work with stainless steel, but no material is too difficult to work with. Materials and SFM are a bit like speed limits on the road, Hastelloy is like a 25 MPH zone, and Aluminum is like the Autobahn. Superalloys require patience and the right recipe.

What sets Octane Workholding apart from the rest of the competition?

I think people appreciate honest companies that actually engage with their customers.  Treating every customer with the same respect, no matter the size of their company. Social media has made helping anyone that needs it, a message away. Whether individuals buy our products or not, we believe the whole industry benefits from the freely available educational materials.

Can you talk about the coolest/most interesting project you have worked on?

We do a lot of neat work but one project especially was great to work on. It is also one of the few that can be made public. Making 11.00″ Custom Scissors for the first time. These Scissors quickly became an obsession once work began on them. Programming them was the first step. Machining them without creating time-consuming custom fixtures was the next challenge. Once they were machined the real fun began.

Having never made Scissors or Knives professionally, I knew the next part would be a learning experience. After ordering some fine grit belts for our sanders, the polishing and sharpening had begun. To begin, I went about polishing the handles and rough sharpening to establish a reference edge on the blades.

Having some paper on hand it was time to give them a try. Success, they cut paper! Now for the real test, they were being created to cut plastic bags. Dread started to creep in as the first cut simply folded the bag in half. This was not good. Ok, what is wrong here? These feel razor-sharp, but they are paperweights at this point. Back to the drawing board. After doing some research on the great UK makers continuing this art, a hollow grind seemed like the solution.

What do we have that can do a hollow grind? A small wheel will put a deep radius if brought back to the blade. I have to make a large wheel so the hollow grind can be shallow. I’ve got it, a faceplate adapter mounted to the Old South Bend, some sandpaper glued to the outside should work! So it began, the journey into learning to hollow grind.

After hours of making things worse and worse, I cannot bring the grind from edge to edge smoothly. Some more research and it seems the technique is to “turn the key”. Wow, it feels unnatural but it works! Finally, a successful hollow grind is performed.

Now for the real art of Scissormaking, the Putter- (fine Scissor Craftsmen which I am not) must sharpen and skillfully assemble them. The final act is to bow the blades carefully such that the edges intersect. They must meet perfectly along the length of the blade as they cross.

One more test, they cut the plastic bag as it passed right through it. This was one of the best moments in my career as a Machinist.

What are your current product offerings?

Our best-selling product is our t-slot cover, The Octane Chip Guard. We also currently offer mounts that offset your Renishaw Tool Setter. Table space is a premium for any milling machine. When the Tool Setter is outside the work envelope, additional work holding or parts can be placed. 

We also offer a T-Slot Drop in Workstop, our drop in workstops can be added at any time, even when access to the end of the t-slot is blocked. This adds a lot of flexibility to set up parts, especially if you forgot to add them beforehand (has happened more than I care to admit). There are a lot of products waiting to be released, but the demand for our t-slot covers has taken priority for now.

Having machined thousands of parts with unique setups, a product that enabled quick changeovers was essential. Cleaning a t-slot is a job Machinists have dreaded for a very long time.  Being silicone, it is extremely easy to trim a piece to fit any setup. Setting up a job for production requires only a few extra minutes to place our t-slot covers. One big problem with vertical machining centers is chip evacuation. Not only does covering the t-slot prevent chips from ever entering the groove, but it actually promotes flushing of every corner of sheet metal. Flood coolant normally is trapped within the grooves, which prevents any chance of the chips being evacuated. Unattended operation is always the goal with any CNC machine, our Chip Guard allows an operator to open the doors to a clean machine. In-process chip fans or automatic washdowns are possible. Safety is also a big issue for any shop. Most Machinists have encountered a chip ricocheting from the t-slots back at their eyes. The color options add a sleek look to any machine. We also offer black for an incognito approach.

Why is high quality tool performance important to you?

Manufacturing is all about process reliability. You may save a few dollars on a tool, but end up paying dividends when said tool fails unexpectedly. A quality tool that increases performance or extends unattended operation, is critical.

Can you talk about a time that Harvey Tool or Helical products really came through and helped you?

Aside from Harvey having tools available as standard, which would be a custom item for the majority of companies. We buy chamfer mills regularly for finishing bevels. The angle being accurate is paramount for finishing. If the angle is off at all, a step can be felt on the finished face. Being confident that a tool that is programmed to cut a feature is accurate, saves us a lot of time. We also rough some heavy stainless steel beveled rings. The heavy chips accumulate due to the 2.00” length of cut., so the solution to this problem was the following chipbreaker endmill – 5 FLUTE, CORNER RADIUS – CHIPBREAKER ROUGHER, VARIABLE PITCH (APLUS).  We are all familiar with the corncob style roughing endmills, which actually create chips that are too small, causing those chips to end up getting into the coolant tank. Helical chipbreaker endmills create a swarf that is the perfect size, as it fits neatly into a container for recycling. The other added benefit is tool life. The bevel rings tend to trap the swarf inside themselves, which can lead to recutting chips that were destroying tool life. The chips were able to be evacuated easily which lead to a 4x’s increase in tool life and a process we could walk away from confidently.

We noticed the education section on your website, not too many companies will add these sections, why do you feel it is important to spread knowledge?

The world saw more technological advancement in 100 years than in all recorded history through manufacturing.  While I may not be part of the next great advancement for humanity, perhaps teaching an aspiring Engineer, will lead to one. Providing the tools for brilliant individuals to go out and make an idea a reality, is something we are committed to. Future generations need to understand how critical manufacturing is to our way of life. 

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

Learn cad/cam first. Watching YouTube tutorials and educational content likes ours can help accelerate the learning curve. Becoming proficient as a programmer and designer can lead to higher starting salaries. If you can walk into a shop with some knowledge of programming, you may bypass a lot of the red tape companies might present to a new employee. Machining is often the easiest part, work holding and programming are often the biggest hurdles. Not everything has been invented yet, perhaps your niche will be making ornate pens, flashlights, knives, firearm parts, etc., creative designs are always in demand. Many successful businesses started in a garage with a hobby machine. Designing your own products can lead to a booming business that can sustain your family and eventually your employees’ families. 

Is there anything else you would like to share with the In The Loupe community?

We are adding more and more educational material to our website.  It’s definitely worth bookmarking for anyone interested in learning more about this trade.

  • Speeds and feeds for turning, drilling, surface finish charts, etc.
  • Threading data like you would find in the Machinist’s handbook, but easier to find and read.
  • Educational articles on topics like quoting, lathe education, mill education etc.
  • Fun DIY projects you can make, like a tap follower.
  • Programming examples and curriculum are in progress with more information being added.

To learn more about Octane Workholding find their website here. Also, you can follow them on Instagram @octane_workholding.

Olson Manufacturing – Featured Customer

Featured Image Courtesy of Logan Olson, Olson Manufacturing

Located in northern California, Olson Manufacturing specializes in handcrafted, customizable golf products that are made with utmost attention to detail from the highest quality materials. Logan Olson, its owner, was introduced to the game of golf by his grandparents at a young age and fell in love with the sport, especially how individualized it is, and how one’s own effort and dedication is paramount. It is because of this love of golf that Logan began designing, and making, his own putters. Soon after, Olson Machining was born.

Now with years under his belt, Logan took time to reflect about Olson Manufacturing, his passion for golf, high-quality tooling, and where his inspiration for his designs originated.

Photo Courtesy of: Logan Olson, Olson Manufacturing

How did you get started and learn how to machine?

I got started in manufacturing coincidentally with making putters: A project that went from a solely digital design to learning a CAD program. It turned into something I wanted to bring into tangible space. A friend of mine introduced me to a manual machinist that had a small machine shop at his house. He had just purchased a personal hobby-sized CNC machine and was kind enough to let me hobble my way through learning the fundamentals of machining on it to design a putter. A year later, I held a barely recognizable chattery mess of a putter and my journey was just beginning.

Where does your passion for golf come from?

I was introduced to the game of golf early on by my grandparents. The individual nature of the game, surrounded by the need to depend on your own effort and dedication as a means to success, has really paved the way for me as a business owner. The need for honesty and integrity, even when it might be easier to take the other road out, has allowed me to stick through the challenging aspects of creating a machine shop and allow my business to thrive in this fast pace, ever-changing world.

What is the inspiration in your designs?

From a design aspect, my number one priority is to do my absolute best to execute the task of creating the best putter I can for the end-user. Customization, additional design aspects, as well as other details, are a welcome addition to a putter that will perform at the highest level. When it comes to the design of creating a custom build, I try to forget that the piece I am working on is a putter altogether and pull my inspiration from other places and different crafts.

It’s always fun when people ask what I do as a machinist to tell them I make golf clubs. There’s always a hesitant humorous laugh as they respond with an, “oh that’s nice, or good for you”. That always seems to change as soon as I show them what I actually make.  The following response is usually more on the stream of “you seriously make these, or wow, that’s not at all what I expected.” The detailed craftsmanship of sword makers, clockmakers, and jewelers is where I try to pull my main inspiration from.

 I do a lot of commissioned work for customers ordering a specific putter that they themselves design, however, I think my true voice as an artist and machinist lies with the putters I make where the designs can flow out of my own imagination with no guidelines or restrictions.

What is your favorite putter you’ve designed?

I’ve had the opportunity to create a ton of really cool and unique projects in my years as a putter maker. It’s really hard to pick out a favorite. I try to say that my favorite putter I’ve ever made is the one I’m currently working on or excited about. I could probably make a list of the top 20 maybe, but picking an individualistic favorite would be tough.

Who is the most famous contact that you have worked on a project with?

I’ve been lucky enough to work with a handful of professionals on the PGA tour as well as the LPA tour and Web.com tours. Feedback from this caliber of players is really the driving force of development for what I do. They can offer some of the most keynotes that help drive changes every year. I have a hard time picking apart a favorite project, but every time a professional golfer comes aboard I always seem to learn something new.

What sets Olson Manufacturing apart from the competition?

In a world where mass production and system efficiency control the consumer market, utilizing old world craftsmanship in companion with cutting edge technology, I can create one of a kind personalized and unique products. That’s not a touch you can find buying something off of a shelf. Knowing that only 1 pair of hands might have spent hours, days, even weeks just creating a putter, I think is something a person holds value to once they acquire one of my putters.

What machines do you currently have in your shop and what materials are you machining?

I use all vertical mills at my shop. With the exception of one of my largest machines, having a 4th axis. Everything I run is all 3 axis machining. I really cut everything under the sun. The bulk of my machining consists of stainless steel, mild alloy carbon steel, and aluminum, for fixture making. However, with that said, I do a very large amount of copper as well. The bulk majority of my inlay work is done in superalloys and some exotic blends such as Zirconium-Titanium alloys, Titanium Damascus (Timascus), pre-hardened high carbon Damascus steels, mother of pearl, bronze, and a handful of other materials.

Why is high quality tool performance important to you?

When I’m working in an environment where the part I am making is a one-shot kind of deal or the material is incredibly hard to get/ expensive, not having the ability to remake the part is why customer support and applications engineers are indispensable. When you’re off purchasing a cheap tool from an unknown company you are unlikely to be able to pick up the phone and say “hey, I’ve got a .030” tool going 1” deep in titanium, this tool can’t break haha can you help me out?”

I can count back just in the last year at least a dozen times I’ve spoken with a Harvey Tool rep on one of my micro tools for a cutting recipe recommendation for an application that kept me out of the dog house. I think we could all talk about coating, cutting life, and tool performance all day long, but I could argue that being able to make a phone call and have an engineer reassure you something will work, is the most important thing of all when it comes to quality tool performance.

What is the smallest Harvey tool you have used and the largest Helical tool?

I’ve used a .02” diameter 3 flute tool for stainless and carbon steel, which would likely be the smallest. I regularly store a .04” tool in my tool changer for pocketing on small inlay work. I used to be scared to sneeze on them in fear of them breaking, now they’re as dependable as any tool in my library and I require them daily for all kinds of machine work. The largest tool I run from Helical is a 6 flute ½” endmill for HEM roughing. I find that’s really as large as I need to go.

If heavier cutting is necessary I’ll lean on an insert tool. I really think some people would be amazed though, at the MRR you can get with a ½” tool. These modern toolpaths are incredibly powerful in comparison to some of the older style machining strategies. Give me a ½” tool in stainless full depth at 250 inches a minute and I can move some metal.

Can you talk about a time that Harvey Tool or Helical products really came through and helped your business?

This would go back to one of my earlier answers for the customer support argument. I was running a billet of pre-hardened Damascus steel for a putter I was making. I don’t know if you’re familiar with Damascus at all, but if you picture high carbon steel blended, smashed, and forged together with a nickel alloy, then hardened, I think you can paint a picture. Oh yeah, and nickel alloys are famously fun to machine… think Inconel, Monel, and Hastelloy… fun stuff. So take that billet and make a putter out of it haha.

Anyways, this stuff is harder than a coffin nail and is eating my 80 dollar endmills for breakfast like it skipped dinner the night before. I was down to my last ½” tool that could do the machine work on this putter and didn’t know what I was going to do. I called up Helical, and an applications engineer not only gave me a recipe that ended up saving me but sent me the skew for a tool that worked way better than the one I had in the spindle. I ordered a package of them, and ever since that day, they are my go-to in Damascus.

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

My biggest piece of advice would be to learn as much as you can. In today’s world, the internet is an incredibly powerful tool and platform for the machining community. There is basically a video out there somewhere you can watch that can probably answer any question you might have. It’s insane. I’m 24 years old and started as a machinist at 19-20. There is absolutely no way I could have gotten to where I am today without countless hours of YouTube scrolling and video binge-watching. It’s great stuff and you should soak it in like a sponge as fast as you can. 30 years ago the machinists would look at the stuff we are doing today and call it Wizardry. We truly are living in an incredible time. Live, learn and love what you do.

To see more of Logan and Olson Manufacturing, you can follow him on Instagram @olsonmfg

R & S Machining – Featured Customer

Featured Image Courtesy of R & S Machining

Located in St. Louis, Missouri, R & S Machining specializes in 4 & 5 axis machining and manufacturing of aerospace components. Since R & S was founded in 1992, they have instilled a spirit of hard work and determination to exceed customer expectations. Equipped with up-to-date machines and automation, R & S Machining has high-quality equipment to keep them as efficient as possible to stay ahead of the competition. The highly skilled men and women operating the manufacturing facility are committed to a high quality standard to meet all customer requirements. Because of this commitment, R & S Machining has been able to expand its facilities in the past four years by more than 225,000 square feet.

We were able to get in touch with Matthew Roderick, the lead programmer for R & S Machining. Matthew took some time out of his busy schedule to answer some questions about R & S Machining, and how the company continues to grow.

Photo Courtesy of: R & S Machining

Can you tell us a little about R & S Machining?

R & S Machining is dedicated to continual improvement and growth. We strive to buy very high quality machines and tooling. We also equip most of our machines with automation. Whether it is a bar feeder, pallet changer, FMS, or robot, nearly all our machines have some form of automation to increase our lights out production. In the past 4 years, we have built a new facility and purchased a new facility. We have grown by more than 225,000 square feet and 35 employees in this timespan. With the backing of our ownership, continued success and relationships with our customers, very dedicated employees, and high-quality reliable manufacturing equipment, we are in a league of our own and continue to strive towards our goal of becoming the powerhouse manufacturing company of the Midwest.

R & S Machining currently uses Hermie, Okuma, Makino, and Kenichi machines in the facility, while utilizing CAM/CAD software such as Siemens NX, Catia, and Mastercam.

How did R & S get into Aerospace and Defense Manufacturing?

Our president worked at Boeing for 10 years. When he left to start his own company, we were given an opportunity with the Boeing Company to manufacture aerospace and defense components based on the quality of work that our President produced during his time with them. We continued to produce high quality products with an emphasis on on-time delivery and the rest is history.

Photo Courtesy of: R & S Machining

What sets R & S apart from the rest of the competitors?

We take on all the work that our competitors no quote or refuse to do. The complexity of parts that flow through this shop is like no other place. We believe there is no other company that can produce the complexity level of parts that we make in the time frames we are given by our customers.

Customer satisfaction is maintained through effectively applying the quality system. Continued training and process review enable R & S Machining to meet customers’ ever-changing requirements. 

What is your favorite project you have had come through the shop?

We manufacture Inlet Ducts for a variety of Fighter Jets. The complexity of these parts is unmatched and the creativity in programming the parts in the CAM system has to be at its peak. Some of these parts require programs of 600+ toolpaths with a majority of them being full 5axis simultaneous paths. Then, when you get to see the machine throwing a 1,100 pound block around like it’s nothing at 2000 IPM in full 5axis simultaneous motion, it’s pretty humbling.

Photo Courtesy of: R & S Machining

What is your connection with the Missouri SkillsUSA Competition?

SkillsUSA is a nonprofit national education association that serves middle school, high school, and college/postsecondary students preparing for careers in trade, technical, and skilled service (including health) occupations. SkillsUSA’s mission is to empower its members to become world class workers, leaders, and responsible American citizens. It emphasizes total quality at work—high ethical standards, superior work skills, lifelong education, and pride in the dignity of work.

Over the past 4 years, we have had many of our employees participate and win in the competition. We have had 5 employees win the district championship, 5 employees win the state championship, and 3 employees win the national championship.

Photo Courtesy of: R & S Machining

Why is high quality tool performance important to you?

We rely on high quality tool performance to meet the tolerancing demands of our customers. Our tolerances range from hole tolerances of +.002″/-.001″, thickness tolerances of +-.01″, profile tolerances of .03″, critical hole tolerances of +-.0002″, and critical hole true position tolerances of .007″. We also rely heavily on lights-out run time overnight, so having a high quality tool that you know is still going to be cutting effectively in the morning and throughout the night is critical to our operation.

We had a 50+ quantity stainless steel job that we were only getting 2-3 parts per tool using tools from a different manufacturer. We changed our tool to a Helical endmill and left everything else the same and made over 30 parts before having to change out the tool.

Photo Courtesy of: R & S Machining

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

There are tons of cool and flashy things out there, but you can not skip the fundamentals. They are the building block to your entire career and they are the concepts you will use every single day. Use the technology to further your skills, not the basis of your skills. At the end of the day, you always have to know feeds and speeds, depth of cuts, work holding, and what you can get away with.

Is there anything else you would like to share with the In The Loupe community?

Helical tooling is unmatched in the HEM hard metal category. These tools have changed the way we manufacture parts and give us the confidence we need to accomplish our high precision and complex parts.

If you want to see what is next for R & S Machining or reach out and ask them some questions, you can follow them on Instagram @randsmachine.

The Secret Mechanics of High Feed End Mills

A High Feed End Mill is a type of High-Efficiency Milling (HEM) tool with a specialized end profile that allows the tool to utilize chip thinning to have dramatically increased feed rates. These tools are meant to operate with an extremely low axial depth so that the cutting action takes place along the curved edge of the bottom profile. This allows for a few different phenomena to occur:

  • The low lead angle causes most of the cutting force to be transferred axially back into the spindle. This amounts to less deflection, as there is much less radial force pushing the cutter off its center axis.
  • The extended curved profile of the bottom edge causes a chip thinning effect that allows for aggressive feed rates.

The Low Lead Angle of a High Feed End Mill

As seen in Figure 1 below, when a High Feed End Mill is properly engaged in a workpiece, the low lead angle, combined with a low axial depth of cut, transfers the majority of the cutting force upward along the center axis of the tool. A low amount of radial force allows for longer reaches to be employed without the adverse effects of chatter, which will lead to tool failure. This is beneficial for applications that require a low amount of radial force, such as machining thin walls or contouring deep pockets.

high feed mill roughing
Figure 1: Isometric view of a feed mill engaged in a straight roughing pass (left), A snapshot front-facing view of this cut (right)

Feed Mills Have Aggressive Feed Rates

Figure 1 also depicts an instantaneous snapshot of the chip being formed when engaged in a proper roughing tool path. Notice how the chip (marked by diagonal lines) thins as it approaches the center axis of the tool. This is due to the curved geometry of the bottom edge. Because of this chip thinning phenomenon, the feed of the tool must be increased so that the tool is actively engaged in cutting and does not rub against the workpiece. Rubbing will increase friction, which in turn raises the level of heat around the cutting zone and causes premature tool wear. Because this tool requires an increased chip load to maintain a viable cutting edge, the tool has been given the name “High Feed Mill.”

high feed end mill ad

Other Phenomena Due to Curved Geometry of Bottom Edge

The curved geometry of the bottom edge also sanctions for the following actions to occur:

  • A programmable radius being added to a CAM tool path
  • Scallops forming during facing operations
  • Different-shaped chips created during slotting applications, compared to HEM roughing

Programmable Radius

Helical Solutions’ High Feed End Mills has a double radius bottom edge design. Because of this, the exact profile cannot be easily programmed by some CAM software. Therefore, a theoretical radius is used to allow for easy integration.  Simply program a bullnose tool path and use the theoretical radius (seen below in Figure 2) from the dimensions table as the corner radius.

high feed mill programmable radius
Figure 2: Programmable radius of a double radius profile tool

Managing Scallops

A scallop is a cusp of material left behind by cutting tools with curved profiles. Three major factors that determine the height and width of scallops are:

  1. Axial Depth of Cut
  2. Radial Depth of Cut
  3. Curvature of Bottom Edge or Lead Angle

Figure 3 below is a depiction of the scallop profile of a typical roughing cut with a 65% radial step over and 4% axial depth of cut. The shaded region represents the scallop that is left behind after 2 roughing passes and runs parallel to the tool path.

roughing cut scallop profile
Figure 3: Back view of roughing cut with a 65% radial step over

Figures 4 and 5 show the effects of radial and axial depth of cuts on the height and width of scallops. These figures should be viewed in the context of Figure 3. Percentage by diameter is used rather than standard units of measurement to show that this effect can be predicted at any tool size. Figure 4 shows that a scallop begins to form when the tool is programmed to have a radial step over between 35% and 40%. The height increases exponentially until it is maximized at the axial depth of cut. Figure 5 shows that there is a linear relationship between the radial step over and scallop width. No relationship is seen between scallop width and axial depth of cut as long as ADOC and the radius of curvature of the bottom cutting edge remains consistent.

graph of scallop height versus depth of cut
Figure 4: Graph of Scallop Height vs. Depth of Cut
graph of scallop width versus depth of cut
Figure 5: Scallop Width vs. Depth of Cut

From the graphs in Figures 4 and 5 we get the following equations for scallop dimensions.

Notes regarding these equations:

  • These equations are only applicable for Helical Solutions High Feed End Mills
  • These equations are approximations
  • Scallop height equation is inaccurate after the axial depth of cut is reached
  • RDOC is in terms of diameter percentage (.55 x Diameter, .65 x Diameter, etc…)

Shop Helical Solutions’ Fully Stock Selection of High Feed End Mills

Curvature of the Bottom Edge of High Feed End Mills

The smaller the radius of curvature, the larger the height of the scallop. For example, the large partial radius of the Helical Solutions High Feed End Mill bottom cutting edge will leave a smaller scallop when compared to a ball end mill programmed with the same tool path. Figure 6 shows a side by side comparison of a ball end mill and high feed mill with the same radial and axial depth of cut. The scallop width and height are noticeably greater for the ball end mill because it has a smaller radius of curvature.

feed mill versus ball end mill
Figure 6: Scallop diagram of High Feed Mill and Ball End Mill with the same workpiece engagement

Full Slotting

When slotting, the feed rate should be greatly reduced relative to roughing as a greater portion of the bottom cutting edge is engaged. As shown in Figure 7, the axial step down does not equate to the axial engagement. Once engaged in a full slot, the chip becomes a complex shape. When viewing the chip from the side, you can see that the tool is not cutting the entirety of the axial engagement at one point in time. The chip follows the contour on the slot cut in the form of the bottom edge of the tool. Because of this phenomenon, the chip dips down to the lowest point of the slot and then back up to the highest point of axial engagement along the side. This creates a long thin chip that can clog up the small flute valleys of the tool, leading to premature tool failure. This can be solved by decreasing the feed rate and increasing the amount of coolant used in the operation.

high feed mill chip formation
Figure 7: Formation of a chip when a feed mill is engaged in a full slotting operation.

In summary, the curved profile of the bottom edge of the tool allows for higher feed rates when high feed milling, because of the chipping thinning effect it creates with its low lead angle. This low lead angle also distributes cutting forces axially rather than radially, reducing the amount of chatter that a normal end mill might experience under the same conditions. Machinists must be careful though as the curved bottom edge also allows for the formation of scallops, requires a programmable radius when using some CAM packages, and make slotting not nearly as productive as roughing operations.

Hybrid Machining – Featured Customer

Featured Image Courtesy of Jeff Robinson, Hybrid Machining

Located in Holland, MI, Hybrid Machining uses machining skills combined with 3 different 3D printing technologies to manufacture complex projects. Hybrid Machining is a manufacturing company that can take the customer’s design from start to finish, allowing customers to dictate their path. Rather than focusing on a single product, Hybrid has listened to customer needs and presented solutions that, in many cases, customers didn’t know were possible. Jeff Robinson, the owner, took some time out of his day to answer some questions about Hybrid Machining.

How did you get into manufacturing?  

I started working in an architectural shop during my high school years.  I quickly realized that there was a more advanced part of the industry that I was missing out on. Therefore, I started researching CNC Routing.  I fell in love with the technology and have been studying it ever since. 

What sort of machines and materials do you use in your shop?

We currently run a Datron Neo, Fanuc Robodrill, and a CR Onsrud 5-axis Router. We work primarily with wood, plastic, and non-ferrous materials. We currently use Autodesk Fusion 360, FeatureCAM, Powermill, Vectric Aspire, and AlphaCAM for CAM.  For CAD, we run Fusion 360, Inventor, and Solidworks.

hybrid machining datron neo
Photo Courtesy of: Jeff Robinson, Hybrid Machining

When did you start using 3D printing and how has it benefitted you?

I have been 3D printing for just over a year.  It was the first technology that we initiated here at Hybrid Machining, and it has allowed us to provide the best solution to the customer no matter what the requirements are. By expanding into 3D printing, we can help the customer decide which technology will work the best for their part. Many times, we take the “Hybrid” approach and use both additive and subtractive technologies together.

How have you adapted during the Covid-19 outbreak and how has it changed your business?

We started by stopping normal production to form a non-profit called 3DC19 with other local, small business owners with the sole purpose of 3D printing and assembling plastic face shields.  Hybrid Machining became the distribution center for the efforts.  Collectively, we produced and donated 75K articles of PPE to local hospitals, nursing homes, doctor offices, and first responders.  You can learn more about the efforts at www.3DC19.com. We have also been machining a lot of acrylic face guards for customers so that we can help them to get their office staff back to work safely. 

fanuc robodrill machine
Photo Courtesy of: Jeff Robinson, Hybrid Machining

What sets Hybrid Machining apart from the rest of the manufacturing community? 

We have a serious passion for educating our youth and local businesses on the rapid changes currently happening in the manufacturing industry and preparing them for the impact that Industry 4.0 will have on our lives in the future.  We want to produce knowledgeable people just as much as we produce products, and we do this in our unique Learning Lab.  We team up with local schools, vocational schools, and community colleges to help them spread the word about manufacturing.  We also intend to do ‘Lunch and Learns’ with local businesses to help them understand what other manufacturing methods and advanced materials are available on the market today.

What is the coolest project you have had come through the shop?

Many years ago, at my previous shop, we worked on the presidential handrail that the last three presidents stood behind during the inauguration.

hybrid machining metal business card
Photo Courtesy of: Jeff Robinson, Hybrid Machining

Are you using HEM techniques to improve cycle times? 

Yes, we use a couple of the fastest and most nimble machines on the market: the Datron NEO and the Fanuc Robodrill.  We leverage the machine’s tools’ high accelerations and deceleration rates, along with HEM, to drastically reduce cycle times for our customers.  This allows us to be competitive against over-seas importers.

What do you have to lose other than cycle time? You purchased the entire tool, not just the tip, so use it!  You will be surprised how the different the machine will sound and you can get parts done faster with less tool wear.

Why is high quality tool performance important to you?

The tooling is super important to the success of a project because the tool is what is doing the work.  I like to tell people, “Why would you buy a high-end sports car with all bells and whistles and then put crappy tires on it?  All that power and handling is worthless unless you have good tires.”  The same goes for tooling.  You can have a half-million-dollar machine that is super-fast and accurate and yet still produce a terrible part with cheap tooling. 

When was a time that Harvey Tool, Helical Solutions, or Micro 100 saved the day?

Harvey Tool helped me get through some tough composite projects in the past.  Their technical support team was extremely knowledgeable on the subject matter and helped me pick the right tool and parameters to get the job done. 

machined metal part from hybrid machining
Photo Courtesy of: Jeff Robinson, Hybrid Machining

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

NEVER STOP LEARNING.  Things may be going great at first and you think you have it all figured out, but then a new technology comes and swipes you off your feet.  Spend your spare time studying industry trends, talking to other business leaders, new and old, and preparing for the future.

 Is there anything else you would like to share with the “In The Loupe” community?

We are extremely thankful that Harvey Tool spends a lot of time developing ‘material-specific’ tooling.  We spend 90% of our time in that section of the catalog.  We recently tested out the new wood cutters and are extremely happy. We pushed these tools at speeds and feeds that are unbelievable.  We also use the Harvey Tool plastic cutters on a regular basis. 

Here at Hybrid Machining, we are blending the lines between routing and milling.  For many decades, the line had been fairly clear. There were certain types of jobs you ran on certain types of machines.  We are blurring those lines and are using the best tools for the jobs.  For instance, we use the 24K RPM spindle on the Robodrill to run it more like a router than a mill.  Therefore, we call it the “RoboRouter”.  We can produce wood and plastic parts at unbelievable speeds while achieving surface finishes that are off the charts.  This is not conventional practice, but the team at Hybrid Machining is willing to blaze the path forward for others to follow.

To check out more about Hybrid Machining go to their website or follow them on social media!

Achieving Success in CNC Woodworking

Developing a Successful Cutting Direction Strategy

There are a number of factors that can affect the machining practices of wood in woodworking. One that comes up a lot for certain hardwoods is the cutting direction, specifically in relation to the grain pattern of the wood. Wood is an anisotropic material. This means that different material properties are exhibited in different cutting directions. In terms of lumber, there are different structural grades of wood related to grain orientation. If the average direction of the cellulose fibers are parallel to the sides of the piece of lumber, then the grains are said to be straight. Any deviation from this parallel line and the board is considered to be “cross-grain”. Figure 1 below depicts a mostly straight grain board with arrows indicating the different axes. Each of these axes exhibits different sets of mechanical properties. Because of these differences, one must be conscious of the tool path in woodworking and minimize the amount of cutting forces placed on the cutter in order to maximize its tool life.

straight grain wood board with woodworking axes
Figure 1: Mostly straight grain board with arrows indicating different axes

Cutting perpendicular to the grain is known as cutting “across the grain” in woodworking. In Figure 1 above, this would be considered cutting in the radial or tangential direction. Cutting parallel to the grain is known as cutting “along the grain” (longitudinally in terms of Figure 1). The closer you are to cutting at 90° to the grain of the wood in any direction, the larger the cutting force will be. For example, a tool with its center axis parallel to the tangential direction and a tool path along the longitudinal direction would have less wear than a tool with the same center axis but moving in the radial direction. The second type of tool orientation is cutting across more grain boundaries and therefore yields greater cutting forces. However, you must be careful when cutting along the grain as this can cause tear-outs and lead to a poor surface finish.

The Proper Formation of Wood Chips With CNC Woodworking

When cutting wood parallel to the grain, there are three basic types of chips that are formed. When cutting perpendicular to the grain, the chip types generally fall into these same 3 categories, but with much more variability due to the wide range in wood properties with respect to the grain direction.

Type 1 Chips

Type 1 chips are formed when wood splits ahead of the cutting edge through cleavage until failure in bending occurs as a cantilever beam. A large force perpendicular to the shear plane is produced, causing the wood ahead of the cutting edge to split, forming this tiny cantilever beam. When the upward force finally exceeds the strength of this tiny beam, it breaks off.  These types of chips cause comparatively little wear compared to types 2 and 3, as the material is splitting before coming in contact with the pointed edge. End mills with either extremely high rake or very low rake angles often produce type 1 chips. This is especially true when machining against grain slopes that are greater than 25°. Woods with moisture content less than 8%form discontinuous chips and are at a higher risk of tear-out.

Type 2 Chips

Type 2 chips are the most desirable of the three types in terms of surface finish. They are a result of material failure along a diagonal shear plane, extending from the cutting edge to the workpiece surface. Type 2 chips form when there is a proper balance between the properties of the wood, cutting parameters, and cutter geometry. Woods with a moisture content between 8% and 20%have a much higher chance of forming continuous type 2 chips while leaving a good surface finish.

Type 3 Chips

The last type of chip forms when the rake angle of a cutter is much too low. In this scenario, the cutting force is almost parallel to the direction of travel. This causes a soft material, such as wood, to be crushed rather than sheared away, leaving a poor surface finish. Generally, the surface left behind looks like tiny bundles of wood elements, a surface defect commonly known as “fuzzy grain.” This type of chip occurs more frequently in softwoods as the crushing situation is compounded in low-density woods.

types of wood chips in woodworking
Figure 2: Different types of wooden chips

Extending Tool Life When Woodworking

Speeds & Feeds Rules of Thumb

There are several different categories of tool wear that occur when cnc woodworking. General rules of machining still apply as RPM has the greatest influence on wear rate. Over-feeding can increase tool wear exponentially and also cause tool breakage. As with most machining operations, a balance between these two is essential. If you are looking to increase your productivity by increasing your speed, you must increase your feed proportionally in order to maintain a balance that keeps the tool properly engaged in the material.

Proper Management of Heat

When cutting tools are exposed to high heat, they begin to wear even faster, due to corrosion. The cobalt binder within most carbide tools on the market begins to oxidize and break free of the cutting edge. This sets off a chain reaction, as when the binder is removed, the tungsten carbide breaks away, too. Different species of wood and types of engineered wood have different corrosive behaviors at high temperatures. This is the most consistent type of wear that is observed when machining MDF or particleboard. The wear is due to the chlorine and sulfate salts found in adhesives as this accelerates high-temperature corrosion.  As with aluminum, when the silica content of a wood increases, so too does its corrosiveness.

Generally, increased tool wear is observed in wood with high moisture content. This trait is due to the increased electro-chemical wear caused by the extractives in wood., Moisture content in wood includes substances such as resins, sugars, oils, starches, alkaloids, and tannins in the presence of water. These molecules react with the metallic constitutes of the cutting tool and can dull the cutting edge. Carbide is more resistant to this type of wear compared to high-speed steel.

Best Coatings for Extended Tool Life in Wood

If you want a longer-lasting tool that will maintain its sharp cutting edge (and who doesn’t), you may want to consider an Amorphous Diamond coating. This is an extremely abrasive resistant coating meant for non-ferrous operations in which the temperature of the cutting zone does not exceed 750 °F. This coating type is one of Harvey Tool’s thinnest coatings, therefore minimizing the risk of any edge rounding and maximizing this edge’s durability.

Avoiding Common Woodworking Mishaps

Tear Out

Tear out, sometimes called chipped grain or splintering, is when a chunk of the wood material being machined tears away from the main workpiece and leaves an unappealing defect where it used to be. This is one of the most common defects when machining wood products. There are many different reasons that tear out occurs. Material characteristics are something to be considered. Tear out is more likely to occur if the grain orientation is less than 20°relative to the tool path, the moisture content of the wood is too low, or the density of the wood is too low. Figure 4 shows the grain orientation angle relative to the tool path. In terms of machining parameters, it can also occur if either the chip load, depth of cut, or rake angle is too high.

woodworking grain in relation to tool path
Figure 4: Example of grain orientation angle relative to the tool path

Fuzzy Grain Finish

Fuzzy grain looks like small clumps of wood attached to the newly machined face and occurs when the wood fibers are not severed properly. Low rake or dull cutting tools indent fibers until they tear out from their natural pattern inside, causing type 3 chips to form, resulting in a poor finish. This can be exacerbated by a low feed or depth of cut as the tool is not properly engaged and is plowing material rather than shearing it properly. Softer woods with smaller and lesser amounts of grains are more susceptible to this type of defect. Juvenile wood is known to be particularly liable for fuzzy grain because of its high moisture content.

fuzzy grain wood finish
Figure 5: Example of a fuzzy grain finish

Burn Marks

Burn Marks are a defect that is particularly significant in the case of machining wood, as it is not generally a concern when machining other materials. Dwelling in a spot for too long, not engaging enough of the end mill in a cut, or using dull tools creates an excessive amount of heat through friction, which leaves burn marks. Some woods (such as maple or cherry) are more susceptible to burn marks, therefore tool paths for these types should be programmed sensibly. If you are having a lot of trouble with burn marks in a particular operation, you may want to try spraying the end mill with a commercial lubricant or paste wax. Be careful not to use too much as the excess moisture can cause warping. Increasing your tool engagement or decreasing RPM may also combat burn marks.

burn marks from wood cutter
Figure 6: Example of burn marks

Chip Marks

Chip marks are shallow compressions in the surface of the wood that have been sprayed or pressed into the surface. These defects can swell with an increase in moisture content, worsening the finish even more. This type of blemish is generally caused by poor chip evacuation and can usually be fixed by applying air blast coolant to the cutting region during the operation.

Raised Grain

Raised grain, another common defect of woods, is when one or more portions of the workpiece are slightly lower than the rest. This blemish is particularly a problem when machining softer woods with dull tools as the fibers will tear and deform rather than be cleanly sheared away. This effect is intensified when machining with slow feeds and the wood has a high moisture content. Variations in swelling and shrinking between damaged and undamaged sections of wood exacerbate this flaw. It’s for this reason that raised grain is a common sight on weather-beaten woods. Work holding devices that are set too tight also have a chance of causing raised grain.

Differentiating Harvey Tool Wood Cutting & Plastic Cutting End Mills

Machinists oftentimes use Plastic Cutting End Mills for woodworking, as this tool has very similar internal geometries to that of an End Mill for Wood. Both tools have large flute valleys and sharp cutting edges, advantageous for the machining of both plastic and wood. The main difference between the Harvey Tool plastic cutters and the woodcutters is the wedge angle (a combination of the primary relief and rake angle). The woodcutter line has a lower rake but still has a high relief angle to maintain the sharpness of the cutting edge. The lower rake is designed to not be as “grabby” as the plastic cutters can be when woodworking. It was meant to shear wood and leave a quality surface finish by not causing tear-out.

Harvey Tool’s offering of End Mills for Wood includes both upcut and downcut options. The upcut option is designed for milling natural and engineered woods, featuring a 2-flute style and a wedge angle engineered for shearing wood fiber materials without causing tear out or leaving a fuzzy grain finish. The downcut offering is optimized for milling natural and engineered woods and helps prevent lifting on vacuum tables.

For more help on achieving a successful machining operation, or more information on Harvey Tool’s offering of End Mills for Wood, please contact Harvey Tool’s team of engineers at 800-645-5609.

Harvey Performance Company Opens New 79,000-Square-Foot Manufacturing Plant in Gorham

GORHAM, ME (October 13, 2020) – Harvey Performance Company, the parent company of the Harvey Tool, Helical Solutions, and Micro 100 industrial cutting tool brands, last month opened the doors to a new, 79,000-square-foot, state-of-the-art manufacturing facility in Gorham, Maine, to support the tremendous growth and product demand its brands continue to experience.

Harvey Performance Company was quickly outgrowing its Sanford Drive facility in Gorham, Maine, where Helical Solutions products have been manufactured for more than 15 years. The new manufacturing facility, which is just 5 minutes away on Raceway Drive, will become home to Helical Solutions product manufacturing and will serve as an innovation hub for all Harvey Performance Company brands.

“We couldn’t be more excited about this new facility,” said Harvey Performance Company Senior Vice President of Sales Jerry Gleisner. “We’re quite literally opening the doors to countless opportunities for us to serve our customers in ways unmatched in the industry.”

“This new facility is an exciting step for our business, as this investment will create opportunities for us to continue to grow,” said Harvey Performance Company Vice President of Operations Steve Vatcher. “In light of the COVID-19 Pandemic, we worked closely with state and local officials to ensure that the completion of our new facility was done in a way that prioritized the health and safety of all involved. I couldn’t be more proud of how everyone came together to make this facility a reality during these unprecedented times.

“When it is safe to do so, we look forward to hosting the Gorham community, our neighbors for more than 15 years, at our new home for a ribbon cutting ceremony to share this exciting milestone with us.”

Harvey Performance Company’s New Manufacturing Plant Will:

  • Expand upon its current research and development capabilities to design, test, and manufacture innovative and high performing cutting tools.
  • Accelerate Harvey Performance Company’s new product growth while maintaining its in-stock status and same-day shipping options for all catalog standard items.
  • Host its distributor partners and customers in a state-of-the-art setting that showcases its capabilities.
  • Meet the needs of the market by scaling the size of Harvey Performance Company’s business in the future, through added machines and personnel.
  • Attract, recruit, and retain high-quality employees, engineers, and operators with a high-class work environment.

Schon DSGN – Featured Customer

Featured Image Courtesy of Ian Schon, Schon DSGN

In 2012, engineer Ian Schon wanted to put his skill for design to the test. He decided to challenge himself by designing a normal, everyday item: a pen. His goal was to take the pen from the design concept to manufacturing it within his own shop. Ian designed his pen how he thought a pen should be: durable, reliable, compact, leak-proof, and easy to use. Most of all, though, he wanted the pen to be of a superior quality, not something easily lost or thrown away.

With the design concept in place, Ian started his work on engineering and manufacturing his new pen. He made many prototypes, and with each discovered new features and additions to better his design. Today, Ian manufacturers his pens through local fabrications in Massachusetts, using local supplies. He makes them from 6061 Aluminum, unique in that it molds to its users’ hand, over time. His pens are designed to outlast its user and be passed on through generations.

Ian was kind enough to take time out of his busy schedule to answer some questions about his manufacturing success.

Schon DSGN silver wrist watch with black band
Photo Courtesy of: Ian Schon, Schon DSGN

What sets Schon DSGN apart from competition?

I think I have a unique approach to designing and manufacturing. I design things that I like, and make them the way that I want to.  I don’t rush things out the door. I’m not thinking about scale, growth, making a big shop, etc. I just want to live a simple life where I make cool objects, sell them, and have enough time in the week to sneak out into the woods and ride my bike. This ethos takes the pressure off a lot, and that makes the workflow freer without as much stress as I had in my past career as a product development engineer.

This workflow isn’t for everyone. it’s not a winning combo for massive business success, per se, and if you audited me you would tell me I’m holding back by not scaling and hiring, but I like it. I see myself as a hybrid between artist and entrepreneur. I love doing things start to finish, blank paper to finished part on the machine. Owning that entire workflow allows for harmony of engineering, machining, tooling, finishing, R+D, marketing, etc. Further, it ensures that I don’t miss critical inflection points in the process that are ripe for process evolution and innovation, resulting in a better product in the end.

I’m sure the way I do things will change over time, but for now I’m still figuring things out and since I work largely alone (I have one amazing helper right now assisting with assembly, finishing, and shipping) I have lots of flexibility to change things and not get stuck in my ways.

Also, by working alone, I control the music. Key!

schon dsgn turning metal on lathe
Photo Courtesy of: Ian Schon, Schon DSGN

Where did your passion for pens come from?

My friend Mike had a cool pen he got from a local shop and I was like “man I like that,” so I made one with some “improvements.” At the time, in my mind, they were improvements, but I have learned now that they were preferences, really. I made a crappy pen on a lathe at the MIT MITERS shop back in 2010, and that summer I bought a Clausing lathe on craigslist for $300 and some tooling and started figuring it all out. I made a bunch of pens, wrote with them, kept evolving them, and eventually people asked me to make pens for them.  I didn’t really intend to start a business or anything, I just wanted to make cool stuff and use it. Bottle openers, knives, bike frames, etc. I made lots of stuff. Pens just stuck with me and I kept pushing on it as a project for my design portfolio. Eventually it became something bigger. Turns out my pen preferences were shared with other people.

Schon dsgn gold and copper metal pens
Photo Courtesy of: Ian Schon, Schon DSGN

What is the most difficult product you have had to make and why?

Making watch cases – wow. What an awful part to try and make on a desktop Taig 3 axis mill and a Hardinge lathe in my apartment! I started working on machining watch cases in 2012, and I finished my first one in my apartment in 2015 (to be fair, I was working on lots of other stuff during that time! But yeah, years…). What a journey. Taught me a lot. Biting off more than you can chew is a great way to learn something. 

What is the most interesting product you’ve made?

When I worked at Essential Design in Boston I worked on the front end of a Mass Spectrometer. The requirements on the device were wild. We had high voltage, chemical resistance, crazy tolerances, mechanism design, machining, injection molding – truly a little bit of everything! It was a fun challenge that I was fortunate to be a part of. Biomolecule nanoscale analysis device. Try saying that ten times fast.

I have something fountain pen related in the works now that I find more interesting, and very, very complex, but it’s under wraps a bit longer. Stay tuned. 

Schon dsgn gold and copper metal pens
Photo Courtesy of: Ian Schon, Schon DSGN

Who is the most famous contact that you have worked on a project with?

I have made watches for some incredible customers, but I unfortunately cannot talk about who they are. Most of my watch work outside of my own parts is also under NDA which is a bummer, but hey it was great work regardless.

Same thing with the pens. I know that some of my pen are in the touring cases of a few musicians, one of which is in the rock and roll hall of fame. But I have to keep it tight!

Before leaving to work for myself, I was part of a design team at IDEO in Cambridge that designed the new Simplisafe Home Security System. As an engineer and designer, I got listed on the patents. That wasn’t machining and was more design and engineering of injection molded plastic assemblies,  but it was still cool, though! Cutting my teeth in the design industry before machining helps me a lot with the creative process in the workshop. Lots of overlap.

What capabilities does your shop have?

I utilize Citizen L series sliding headstock machines to run my company. These are Swiss Machines (though made in Japan) with twin spindles and have live tooling for milling operations. I got into this type of machining after getting advice from friends in the industry and subcontracting my work to shops with these style of machines for 7 years.

Beyond the Swiss Machines, I have a new Precision Matthews Manual Mill, a Southbend Model A, a Hardinge Cataract Lathe, and a bunch of smaller Derbyshire lathes and mills. Most of these are for maintenance related tasks – quick mods and fixtures and my watchmaking/R&D stuff. I also have a Bantam Tools Desktop CNC machine on the way, a nice machine for quick milled fixtures in aluminum and nonferrous materials. I tested this machine during their development phases and was really impressed.

What CAM/CAD software are you using?

I use Fusion 360 for quick milled stuff, but most of my parts are programmed by hand since the lathe programming for Swiss work can be done without much CAM. I’m sure I could be doing things better on the programming side, but hey, every day I learn something new. Who knows what I’ll be doing a year or two from now?

schon dsgn turning wrist watch on lathe
Photo Courtesy of: Ian Schon, Schon DSGN

What is your favorite material to work with and why?

Brass and Copper. The chips aren’t stringy, it’s easy to cut quickly and the parts have this nice hefty feel to them. Since I make pens, the weight is a big piece of the feeling of a pen. The only downside is I’m constantly figuring out ways to not dent the parts as they are coming off the machines! My brass parts are like tiny brass mallets and they LOVE to get dinged up in the ejection cycles. I ended up making custom parts catchers and modifying the chutes on the machines to navigate this. I might have some conveyors in my future….yeah. Too many projects!

schon dsgn disassembled wrist watch
Photo Courtesy of: Ian Schon, Schon DSGN

Why is high quality tool performance important to you?

It’s not just important, it’s SUPER important. As a solo machinist running my own machines, being able to call a tooling company and get answers on how I should run a tool, adjust its RPM, feed, DOC, or cutting strategy to get a better result is invaluable. I find that as much as I’m paying for tool performance, I’m also paying for expertise, wisdom and answers. Knowing everything is cool and all (and I know some of you out there know everything under the sun), but since I don’t know everything, it’s so nice to be able to pick up a phone and have someone in my corner. These tech support people are so crucial. Being humble and letting support guide me through my tooling challenges has helped me grow a lot. It’s like having a staff of experienced machinists working at my company, for free! Can’t beat that. Micro 100 and Helical have helped me tons with their great support.

schon dsgn multicolored fountain pens
Photo Courtesy of: Ian Schon, Schon DSGN

When was a time that Harvey, Helical or Micro product really came through and helped your business?

The Helical team (shout out to Dalton) helped me nail some machining on some very wild faceted pens I was working on this month. When I switched to Helical, my finishes got crazy good. I just listened to recommendations, bought a bunch of stuff, and kept trying what Dalton told me to. Eventually, that led to a good recipe and manageable tool wear. It was great!

I also like how representatives from the Harvey/Helical/Micro family often cross reference each other and help me find the right solution, regardless of which company I’m getting it from. Nice system.

The quiet hero in my shop is my Micro 100 quick change system. It just works great. Fast to swap tools, easy to setup, cannot argue with it! Too good. 

Schon DSGN silver wrist watch with black band
Photo Courtesy of: Ian Schon, Schon DSGN

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

Find a mentor who supports you and challenges you. Find a good tooling company, or good tooling companies, and make good relationships with their tech support so you can get answers. Make good relationships with service technicians who can help you fix your machines. Be a good person. Don’t let yourself become a hot head under the pressure of this industry (since it can be hard at times!), cooler heads prevail, always. Be open to seeing things from other viewpoints (in life and in machining), don’t be afraid to flip a part around and start over from square one.

To learn more about Ian and Schon DSGN, follow them @schon_dsgn and @the_schon on Instagram and check out his website. And, to learn more about how Ian got his start in the manufacturing industry, check out this video.

Rennscot LLC – Featured Customer

Featured Image Courtesy of David Bamforth, Rennscot LLC

David Bamforth is the founder and CEO of Rennscot LLC, a manufacturing company based out of Woburn, Massachusetts, which was created to meet product design demands of both individual and commercial clients. From idea to prototype, and eventually to final product, Rennscot LLC prides itself on its ability to make part ideas come to life. David took some time to talk with us about Rennscot LLC, his company’s machining capabilities, and much more.

Assortment of end mills and tool holders at Rennscott LLC
Photo Courtesy of: David Bamforth, Rennscot LLC

What capabilities does your shop have?

We are mostly a mill shop with two verticals and one 5-axis machine. We also have a small bar fed lathe, a larger sub-spindle live-tooling lathe, and some design tools like a Faro Design Scan Arm. We work predominantly with aluminum, but sometimes see brass, stainless, titanium, and steel alloy jobs come through. We use Fusion 360 for everything and currently all 4 of our machines are Haas.

What sets Rennscot LLC apart from the competition?

We are a bit different from most shops because, in addition to machining services, we also offer design services. A lot of our jobs are won because we are a one-stop-shop from idea to producing the final product. Recently we have been making a lot of parts for vehicle restoration. Typically, we are just handed a part and asked to reproduce it.

What is your favorite part of the job?

Problem solving and learning new skills. We are a pretty young team and love being challenged by new projects. We also pride ourselves on being pretty innovative with our machining strategies to help reduce lead times and cost for our customers.

cnc machined metal part from Rennscot LLC
Photo Courtesy of: David Bamforth, Rennscot LLC

Where did your passion for automobiles come from?

Like many, I have always been passionate about cars. I have some great memories of going to car shows with my dad and watching any TV show with a car in it as a kid. Nowadays, I spend my personal time taking our shop development car, a Porsche Cayman, to the track.

What is the coolest product you have made?

We have had some pretty unusual characters bring us some really cool projects. Currently, we are working with a guy from Connecticut on laser scanning a model Mercedes C10 Le Mans car that we will CAD model, so a full-sized car body can be reproduced. It’s a really interesting project, trying to take a 1:43 car and blow it up to full size. Eventually, we will help design and manufacture many of the machined components on this car. Also, we once made a custom billet alternator mount in just 5 days for a 996 Porsche GT3 with a Chevy LS engine in it. We really enjoyed being part of that project and the V8 sounded amazing on track!

cnc machined metal part from Rennscot LLC
Photo Courtesy of: David Bamforth, Rennscot LLC

What is the most difficult product you have made?

We once worked on an enclosure for a handheld x-ray machine. The part was only about 1”x 1.25” x4” and only had .040” walls all around. The main pocket was machined with our go-to Helical ¼” reduced shank end mill. It also had #0-80 taps all along the top edge of the enclosure, making for a few broken taps! It was a pain to get dialed in but once the process was proved out it was really rewarding to get consistent good parts off the will.

Why is high quality tool performance important to you?

Once we started using high quality end mills, we immediately saw an improvement in tool life and surface finish. We also really enjoy using tools that are backed by a company that puts out so much information and resources to help its customers out.

When was a time that Harvey Tool or Helical products really came through and helped your business?

We have had several moments when we hit a wall while building a process for a new part, and Helical’s phone support helped us find the perfect tool for the process. The combination of great phone support, having such a vast array of product offerings, and all of the tools always being in stock has helped my business tremendously.

Rennscot LLC machine shop assortment of harvey tool and helical end mills
Photo Courtesy of: David Bamforth, Rennscot LLC

Are you guys using High Efficiency Milling (HEM) techniques to improve cycle times?

Always! All our mills are spec’ed with HSM and 12k RPM spindles, and we take full advantage of this with chip breaking roughers. Honestly, we are so young that we have only ever used HEM techniques, so I’m honestly just confused by companies that don’t use it. Not using HEM is like not driving a car on the highway because it’s too fast.

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

Machining is probably the most in demand and most satisfying industries that someone can get into now-a-days. There are a lot of companies that are in demand for green machinists who are just eager to learn. I would recommend putting together and sending out a resume to local shops that shows that you have the ability to take on projects and complete them.

If anyone is interested in learning more about what we do our manufacturing website, rennscotmfg.com is a great resource. Also, check us our on Instagram at @rennscot.

How to Optimize Results While Machining With Miniature End Mills

 The machining industry generally considers micromachining and miniature end mills to be any end mill with a diameter under 1/8 of an inch. This is also often the point where tolerances must be held to a tighter window. Because the diameter of a tool is directly related to the strength of a tool, miniature end mills are considerably weaker than their larger counterparts, and therefore, lack of strength must be accounted for when micromachining. If you are using these tools in a repetitive application, then optimization of this process is key.

Key Cutting Differences Between Conventional and Miniature End Mills

Runout

Runout during an operation has a much greater effect on miniature tools, as even a very small amount can have a large impact on the tool engagement and cutting forces. Runout causes the cutting forces to increase due to the uneven engagement of the flutes, prompting some flutes to wear faster than others in conventional tools, and breakage in miniature tools. Tool vibration also impacts the tool life, as the intermittent impacts can cause the tool to chip or, in the case of miniature tools, break. It is extremely important to check the runout of a setup before starting an operation. The example below demonstrates how much of a difference .001” of runout is between a .500” diameter tool and a .031” diameter tool.

chart comparing tool diameter for runout in micromachining
The runout of an operation should not exceed 2% of the tool diameter. Excess runout will lead to a poor surface finish.

Chip Thickness

The ratio between the chip thickness and the edge radius (the edge prep) is much smaller for miniature tools. This phenomena is sometimes called “the size effect” and often leads to an error in the prediction of cutting forces. When the chip thickness-to-edge radius ratio is smaller, the cutter will be more or less ploughing the material rather than shearing it. This ploughing effect is essentially due to the negative rake angle created by the edge radius when cutting a chip with a small thickness.

If this thickness is less than a certain value (this value depends of the tool being used), the material will squeeze underneath the tool. Once the tool passes and there is no chip formation, part of the plowed material recovers elastically. This elastic recovery causes there to be higher cutting forces and friction due to the increased contact area between the tool and the workpiece. These two factors ultimately lead to a greater amount of tool wear and surface roughness.

chart of edge radius in relation to chip thickness for micromachining
Figure 1: (A) Miniature tool operation where the edge radius is greater than the chip thickness (B) Conventional operation where the edge radius is small than the chip thickness

Tool Deflection in Conventional vs. Micromachining Applications

Tool deflection has a much greater impact on the formation of chips and accuracy of the operation in micromachining operations, when compared to conventional operations. Cutting forces concentrated on the side of the tool cause it to bend in the direction opposite the feed. The magnitude of this deflection depends upon the rigidity of the tool and its distance extended from the spindle. Small diameter tools are inherently less stiff compared to larger diameter tools because they have much less material holding them in place during the operation. In theory, doubling the length sticking out of the holder will result in 8 times more deflection. Doubling the diameter of an end mill it will result in 16 times less deflection. If a miniature cutting tool breaks on the first pass, it is most likely due to the deflection force overcoming the strength of the carbide. Here are some ways you can minimize tool deflection.

Workpiece Homogeny

Workpiece homogeny becomes a questionable factor with decreasing tool diameter. This means that a material may not have uniform properties at an exceptionally small scale due to a number of factors, such as container surfaces, insoluble impurities, grain boundaries, and dislocations. This assumption is generally saved for tools that have a cutter diameter below .020”, as the cutting system needs to be extremely small in order for the homogeny of the microstructure of the material to be called into question.

Surface Finish

Micromachining may result in an increased amount of burrs and surface roughness when compared to conventional machining. In milling, burring increases as feed increases, and decreases as speed increases. During a machining operation, chips are created by the compression and shearing of the workpiece material along the primary shear zone. This shear zone can be seen in Figure 2 below. As stated before, the chip thickness-to-edge radius ratio is much higher in miniature applications. Therefore, plastic and elastic deformation zones are created during cutting and are located adjacent to the primary shear zone (Figure 2a). Consequently, when the cutting edge is close to the border of the workpiece, the elastic zone also reaches this border (Figure 2b). Plastic deformation spreads into this area as the cutting edge advances, and more plastic deformation forms at the border due to the connecting elastic deformation zones (Figure 2c). A permanent burr begins to form when the plastic deformation zones connect (Figure 2d) and are expanded once a chip cracks along the slip line (Figure 2e). When the chips finally break off from the edge of the workpiece, a burr is left behind (Figure 2f).

burr formation mechanism using a miniature end mill
Figure 2: Burr formation mechanism using a miniature end mill 

Tool Path Best Practices for Miniature End Mills

Because of the fragility of miniature tools, the tool path must be programmed in such a way as to avoid a sudden amount of cutting force, as well as permit the distribution of cutting forces along multiple axes. For these reasons, the following practices should be considered when writing a program for a miniature tool path:

Ramping Into a Part

Circular ramping is the best practice for moving down axially into a part, as it evenly distributes cutting forces along the x, y, and z planes. If you have to move into a part radially at a certain depth of cut, consider an arching tool path as this gradually loads cutting forces onto the tool instead of all at once.

Micromachining in Circular Paths

You should not use the same speeds and feed for a circular path as you would for a linear path. This is because of an effect called compounded angular velocity. Each tooth on a cutting tool has its own angular velocity when it is active in the spindle. When a circular tool path is used, another angular velocity component is added to the system and, therefore, the teeth on the outer portion of tool path are traveling at a substantially different speed than expected. The feed of the tool must be adjusted depending on whether it is an internal or external circular operation. To find out how to adjust your feed, check out this article on running in circles.

Slotting with a Miniature Tool

Do not approach a miniature slot the same way as you would a larger slot. With a miniature slot, you want as many flutes on the tool as possible, as this increases the rigidity of the tool through a larger core. This decreases the possibility of the tool breaking due to deflection. Because there is less room for chips to evacuate with a higher number of flutes, the axial engagement must be decreased. With larger diameter tools you may be stepping down 50% – 100% of the tool diameter. But when using miniature end mills with a higher flute count, only step down between 5% – 15%, depending on the size of the diameter and risk of deflection. The feed rate should be increased to compensate for the decreased axial engagement. The feed can be increased even high when using a ball nose end mill as chip thinning occurs at these light depths of cut and begins to act like a high feed mill.

Slowing Down Your Feed Around Corners

Corners of a part create an additional amount of cutting forces as more of the tool becomes engaged with the part. For this reason it is beneficial to slow down your feed when machining around corners to gradually introduce the tool to these forces.

Climb Milling vs. Conventional Milling in Micromachining Applications

This is somewhat of a tricky question to answer when it comes to micromachining. Climb milling should be utilized whenever a quality surface finish is called for on the part print. This type of tool path ultimately leads to more predictable/lower cutting forces and therefore higher quality surface finish. In climb milling, the cutter engages the maximum chip thickness at the beginning of the cut, giving it a tendency to push away from the workpiece. This can potentially cause chatter issues if the setup does not have enough rigidity.  In conventional milling, as the cutter rotates back into the cut it pulls itself into the material and increases cutting forces. Conventional milling should be utilized for parts with long thin walls as well as delicate operations.

Combined Roughing and Finishing Operations

These operations should be considered when micromachining tall thin walled parts as in some cases there is not sufficient support for the part for a finishing pass.

Helpful Tips for Achieving Successful Micromachining Operations

Try to minimize runout and deflection as much as possible when micromachining. This can be achieved by using a shrink-fit or press-fit tool holder. Maximize the amount of shank contact with the collet while minimizing the amount of stick-out during an operation. Double check your print and make sure that you have the largest possible end mill because bigger tools mean less deflection.

  • Choose an appropriate depth of cut so that the chip thickness to edge radius ratio is not too small as this will cause a ploughing effect.
  • If possible, test the hardness of the workpiece before machining to confirm the mechanical properties of the material advertised by the vender. This gives the operator an idea of the quality of the material.
  • Use a coated tool if possible when working in ferrous materials due to the excess amount of heat that is generated when machining these types of metals. Tool coatings can increase tool life between 30%-200% and allows for higher speeds, which is key in micro-machining.
  • Consider using a support material to control the advent of burrs during a micromachining application. The support material is deposited on the workpiece surface to provide auxiliary support force as well as increase the stiffness of the original edge of the workpiece. During the operation, the support material burrs and is plastically deformed rather than the workpiece.
  • Use flood coolant to lower cutting forces and a greater surface finish.
  • Scrutinize the tool path that is to be applied as a few adjustments can go a long way in extending the life of a miniature tool.
  • Double-check tool geometry to make sure it is appropriate for the material you are machining. When available, use variable pitch and variable helix tools as this will reduce harmonics at the exceptionally high RPMs that miniature tools are typically run at.
variable pitch versus non-variable pitch
Figure 3: Variable pitch tool (yellow) vs. a non-variable pitch tool (black)