In our last post in this series, we introduced you to AlTiN, a great general purpose coating with a high aluminum content, which is used for machining steel, titanium alloys, Inconel, stainless, and cast iron in both wet and dry environments. In this article, we’re going to kick it up a notch with a coating that has all the advantages of AlTiN, but performs at an even higher level. Meet ALCRO-MAX.
Strong. Stable. Long Lasting.
ALCRO-MAX is a Triple Platit® Coating based on AlCrN (aluminum, chromium, nitride) combined with titanium. Triple Coatings are deposited with 3 sections freely programmed in one batch. ALCRO-MAX is applied to our tools using the Platit high performance physical vapor deposition (PVD) unit right on our shop floor. Keeping the process in-house give us total control on quality and turnaround.
This super-strong coating has been engineered to give an optimum balance between the toughness of the core layer and the abrasion resistance of the top nano-layer. The addition of titanium reduces adhesive wear and chipping compared to conventional AlCrN coatings. It increases the micro-hardness up to 3500Hv and stops the crack propagation through the coating.
When to Use It
ALCRO-MAX is highly suited to machining tool steels; 303, 304 and 316L stainless steel; and Ti-6Al4V or other titanium alloys. These materials have a tendency to generate excessive heat at the contact area. This results in long continuous chips that can weld on to the tool edge, giving you a poor finish and scrapped parts. And you can just imagine what that kind of heat does to tool life. All materials that fall into the “gummy” category require a coating like ALCRO-MAX for increased thermal resistance and extended tool utilization. Our customers use it for wet and MQL (minimum quantity lubrication) application to achieve longer tool life and increased thermal stability. And because it is does not rely on heat to activate the coating, like AlTiN, its performance in wet milling applications noticeably better.
The ability of the cutting edge to shear the work material with as little residual friction as possible after initial contact is critical in producing an end mill that will satisfy the tool life and metal removal demands of today’s manufacturers. That’s why ALCRO-MAX coatings are available on all of our PYSTL series end mills. Of course, we can always add ALCRO-MAX to a custom tool designed specifically to your needs.
Contact us to see if ALCRO-MAX or any of our other coating options will help you achieve better results. Remember, if you can’t find what you need off the shelf, we specialize in custom engineering the right tool for your application.
Gina Hong has been a GWS Tool Group Machine Operator in our Springfield, Massachusetts plant for three and a half years. She’s a skilled maker of our custom cutting tools, and if you told her four years ago it’s where she would be, she probably would not have believed you.
Since she was undecided about going to college, Gina asked a tech instructor in her home town of Asnuntuck, Connecticut, about her next step. Recognizing her skills on the school’s old Bridgeport manual lathe, the teacher suggested she apply for a job with GWS while she made up her mind. It was an excellent piece of advice. Gina admits that she likes working here so much that college is still on the back burner.
“Can I Do This?”
Today, Gina runs a bank of four ANCA MX7 Linear CNC tool grinders. Taking dimensions from a paper print, she programs the machines via the control panel, loads a blank and monitors the run. While you wouldn’t know it today, Gina admits that during her first year, she was convinced she would never learn to do the job effectively. But for each error she made, she gained a piece of knowledge that could be used the next time to make a better product.
That education process continues to this day. “If I get a bad result, I can count on my experience to correct it,” she says. “But there’s always something new for me to learn.” For example, on a recent job, a 350 carbide end mill wasn’t matching spec after the run. Gina adjusted the wheel and checked the core and diameter. Finally, an engineer checked out the machine and found that a loose probe was causing the problem. “I filed that one away for the next time,” she said.
Mastering the Job
The variety of new challenges in each day is what keeps the job exciting for Gina. She may not know the exact nature of the next tooling puzzle to be solved, but she knows whatever it is, she will be ready to analyze the situation and come up with a viable solution.
Gina says her greatest accomplishment so far was mastering the job well enough to run independently. “I thought it was too hard at first, but I gave it a chance and found out I was much more capable than I had even imagined.”
Working for GWS
One of the things Gina likes about working for GWS is the constant flow of new technology into the shop. “The company isn’t afraid to spend money to keep us competitive and give our customers the best tools possible.”
Gina has a pretty full work schedule and says her job is enough of a challenge to satisfy her creative side. She doesn’t need to take on a hobby or participate in sports. “When I have the chance, I just like to relax with the television or hang out with my girlfriends.”
Looking for a Satisfying Career?
GWS Tool Group is on the cutting edge of custom cutting tools, and our facilities in Florida, Indiana, Michigan and Massachusetts are always looking for talented and driven individuals. If you’re curious about the perks and possibilities of a career here, read up on how you can join our team.
Machining metal generates heat, and coatings are all about providing resistance to that heat while also providing some other tangible benefits as well. The make-up of the coating depends on the cutting application and the coating machine itself. Variables like work material, cutting fluid, cutting tool type and even part tolerances can all play roles in coating selection.
Cutting tool coatings are designed to improve wear properties via higher hardness, increased thermal stability and reduced coefficients of friction. In a new series of posts, we’ll review the different types of coatings we offer to make your cutting tools provide better performance. First up: AlTiN.
AlTiN. For when things heat up.
This chemical compound is named for the three elements that make up its composition: Aluminum, Titanium, and Nitride. It, along with most coatings we will discuss in this series, is applied to tools using the PVD (physical vapor deposition) method. While TiAIN is made up of the same basic components, the percentages of aluminum and titanium differ. Based upon the application, one may work slightly better than the other, but for our purposes here we will place them both in the same category.
Once deemed a new innovation, AlTiN is now considered a general purpose coating with high aluminum content. Applied to the tool with a coating thickness between 2-4 microns, it provides excellent heat and oxidation resistance. This is partly due to its nano hardness of 36 gpa (gigapascal – a unit of pressure). AlTiN remains stable at operating temperatures up to 1,292F°. Uncoated tools get into trouble at around 572°F.
One note about AlTiN is its application in wet machining environments (which, obviously, is most of them). Simply put, AlTiN performs best in applications where temperatures are both elevated and stable, as consistently high temperatures essentially activate the aluminum in the coating, improving performance. When run wet, temperatures fluctuate up and down, somewhat reducing the coating’s maximum performance capabilities.
What does all this mean for you? Higher feeds and speeds when machining ferrous materials, for starters. Better tool life, too. AlTiN is a good coating for dry machining and machining titanium alloys, Inconel, stainless alloys, and cast iron.
AlTiN coatings are available on the following GWS tool groups:
• 210 Series – 335 | 3FL | Radius • 215 Series – 335BN | 3FL | Ball Nose • 220 Series – 545 | 5FL | Square & Radius • 240 Series – S94 | 2FL | Chamfer Mill • 241 Series – S94 | 4FL | Chamfer Mill • 243 Series – CM2 | 2FL | 90 deg. | Chamfer + End Mill • 4005 Series – ECO | 2FL | 5xD | Solid | Inch & Metric
And of course, we can always add AlTiN to a custom tool designed specifically to your needs.
Contact us to see if AlTiN or any of our other coating options will help you achieve better results. But whatever you do, don’t run a bare tool. Put a coat on it!
Cutting tool catalogs are full of very good off-the-shelf options for a lot of machining applications. But not every situation has a standard answer. Is it possible that you may save time and even more money by going to a tool tailor-made to your needs? Here are 5 signs that you might be better off going with a customized product.
One: Unsatisfactory Performance
The most obvious sign that a custom tool may serve you better is when you pull a part out of the CNC machine and are not happy with the results. For example, if you feel your surface finish could have been better, or you’re routinely sending pieces off to another operation for polishing or deburring, you could be wasting time and money. Likewise, if you are getting the quality you want, but wish you got more tool life, custom may be the way to go. Constantly stopping the run to replace tools that break prematurely is also an obvious red flag.
Two: Bottlenecks in Production
Simple logic tells us that when you can make a part faster, you reduce the cost per unit and generate more revenue. Along with this, when big rush orders come through the door (and they always do), having the ability to increase throughput makes customers happy in the form of on-time deliveries. If you’re cutting profiles on a part that require multiple tools to complete, especially on turning centers where tool storage is limited, it might be worth investigating whether a custom form tool will do it in one operation. The custom tool, combined with a little tool path reprogramming support from GWS, has the potential to reduce hours into minutes and minutes down to seconds. And as we all know, in manufacturing, every second counts!
Three: Room for Improvement
The best tool out of the catalog may not be the best option for the application. How much in terms of operational performance is it leaving on the table? You probably experimented with different makes and models before you selected the standard tool you are using now. Why not keep that thought process going and really dial in the geometry, coating and substrate to wring out every ounce of performance possible? Custom could open up a whole new world for you.
Four: Slow or Late Delivery
Just because a part is in a catalog doesn’t mean it’s actually on the shelf. Lead time on out of stock tools can stretch from a few days to a few months, depending on the manufacturer and their production backlog. A custom tool means it’s unique to you with no one else to deplete inventory and leave you stranded. With over 150 grinding centers organized in cells to accommodate highly customized work with rapid turnaround times, GWS can fill large volume orders quickly, consistently and with the highest degree of quality. To ensure consistent and on-time-delivery, we even work with our distributors to keep inventory on their shelves dedicated exclusively to individual customers.
Five: Spending Too Much $$$
It may seem counterintuitive that custom tools can save you money. But if you’re a high-production manufacturer using hundreds or even thousands of tools over the course of the year, you could be ordering a hundred or two hundred tools at a time. However, the catalog price is the catalog price. You won’t get a concession for volume because the price has already been set. Custom tool pricing is based on quantity breaks, and as a consequence, often yield cost savings versus pre-defined “stocked standards.”
Getting out of the “stock” mindset and seeking optimum performance for your cutting tool dollar by going “custom” makes sense in today’s manufacturing environment. If you have noticed any of these signs in your operations, contact us and put our expertise to work for you.
Here’s a true story for you. A Tier One supplier was fulfilling a defense contract for titanium components using conventional 40 taper vertical machining centers. The part had a simple turning operation and then was put into the VMC and machined to its final stage. Total cycle time: 5.5 hours.
Enter Mike Littlejohn, Senior Applications Specialist for GWS. Long story short – supplier reduces cycle time to 29 minutes and drops one whole setup. Owner’s jaw drops. He turns to the GM and says, “We’ve been doing this wrong the whole time!”
Just Another Day on the Shop Floor
These are the sort of things GWS specialists, like Mike, do every day. With their background in process analysis and cycle time reduction, they have the ability to re-approach a particular manufacturing process and achieve great results through the use of our custom tooling. When running production quantities, even a quarter of a second cycle time savings on a part could save hours annually and dramatically affect your bottom line. The experience and expertise of our specialists have led customers to hours and hours of cycle time reduction.
The Trouble with Titanium
Titanium is used extensively in the aerospace and medical segments. The problem is it has a tendency to generate excessive heat at the contact area during the machining process. With titanium’s low thermal conductivity characteristics, that heat gets transferred mainly to the cutting tool. This results in long continuous chips that can weld on to the tool edge, giving you a poor finish, or worse yet, out of tolerance parts. And you can just imagine what that kind of heat does to tool life. Feeds and speeds need to be dialed in carefully in order to get any decent tool life at all. All of these characteristics must be taken into account if you want to mill titanium successfully.
Hold Up on Desperate Measures
To solve titanium issues, aerospace companies might be ready to invest in new machinery that costs hundreds of thousands of dollars. Here’s a tip. Consult with one of our specialists on the appropriate tooling on your current machine before breaking the budget for new capital assets.
To serve industries where titanium and other alloys are widely used, GWS has developed a standard cutting tool line that was created with these materials in mind. The PYSTL series comes in different multiple flute variations and coatings. Even more styles are currently in development.
Tailor-Made for Your Application
When you need more than standard tooling, GWS can develop a custom design from a part print or reverse engineer a tool from a part sample. We can design a custom tool that potentially can machine more than one feature at a time.
To us, building a custom tool is like putting together a new recipe. In addition to geometry, we research combinations of substrates and coatings. Because we specialize in custom tools, our specialists have this process down cold. That’s why we’re known for our fast turnarounds for tailor-made products.
If titanium and other space-aged alloys are giving your operators fits and causing a dip in your bottom line, contact us and see if a standard or custom cutting tool from GWS will help give your jaw-dropping results.
Many of the tailor-made cutting tools we engineer for customers are so innovative they are easily adaptable to a wider range of applications than originally anticipated. This doesn’t happen by accident. Our organization is full of highly experienced and talented people who have a knack for both listening to customer feedback and seeing the future potential for each tool they design. Because of this, every custom project we undertake has the potential to develop a new standard tool for our catalog, expanding and strengthening our overall product mix.
Tool Design 101
How does a custom tool become a standard? It’s not rocket science (actually, sometimes it is), but a careful thought process consisting of equal parts of experience, knowledge and communication.
For example, here’s a quick overview of the design process for an end mill. The first step is to marry the tool to the cutting material. There is still a lot of machining in nonferrous aluminum material, especially in the aerospace/aircraft sector. Machine tool builders are busy making machines for that area, which are usually outfitted with high rpm spindles (30k rpm and up) and can feed as fast as 1,000 IPM. It’s up to us to develop the right kind of cutting tool that works in these high-volume removal applications.
This involves calculating the chip load based on the tool diameter to get good chip thickness and generate the proper cutting angle to attain the preferred shearing action.
Communication with the end user during the development process is vital to improve the original design. We stand right by the machine, listen to the customer’s feedback and fine-tune the geometries of the tool until its performance and longevity match our high expectations.
When we have success with a particular design in a certain application, we document it in our master database. The library acts as a starting point when the next request arrives for a similar material and application. Having examples to work from puts us ahead of the game and speeds up delivery times for a new tool.
This is truly where GWS stands apart from the competition. We do not impose limits on ourselves simply because we already have an outstanding standard product portfolio. If a custom tool is required, we pride ourselves on delivering the very best design without prolonged wait times for the end customer.
A critical component of our “custom comes standard” model is our ability to pull resources, develop completely new tooling (be it custom inserts, a complex form tool or redesigned high-performance end mill) and deliver it to the customer in days. With other suppliers, the wait could be weeks or even months. Our capacity also allows us to deliver these tools with scale (a few hundred to a few thousand pieces), to support the largest of demands.
Constant Learning. Practical Applications.
The entire process is actually a little more sophisticated than our simple outline would suggest. Tooling design has gone beyond the typical 4 flute design that used to be the benchmark. Variations today include indexable tooling options, variable helix from flute to flute that eliminate vibration and chatter, eccentric reliefs ground in for better edge support, and edge preparation for better tool life.
The evolution of the best tool is always a moving target. Developments are always on the horizon, from manufacturing and inspection technologies to new carbide substrate compositions and advances in the area of PVD and CVD coatings. To keep pace, our own education process needs to be continuous.
Even understanding the varieties of software customers are using in their process is a must in developing the right cutting tool. A tool for light, high speed Z-level machining will be designed very differently from one for heavy, high-volume milling applications. Understanding the capabilities of a customer’s software enables us to not only design the right tool, but also helps our programmers determine if applying a more efficient toolpath for the customer is possible.
Whether you use a model right out of our catalog or need a custom approach, contact us for a consultation. Either way, we’ll always deliver the cutting tool you need.
Continually changing worn out cutting tools can be a real profit breaker. If you’re machining automotive and aerospace components made out of hardened steel or nickel-based alloys, you really know what we mean. How do you avoid the costly downtime and excessive tooling costs typically associated with these super-hard materials? Find yourself a tougher tool. We offer a full array of standard and custom turning inserts tipped with the hardest substances on Earth.
Cubic Boron Nitride
CBN comes in right behind diamonds on the hardness scale. Unlike other types of boron nitride, it exists as a cubic crystal lattice, like the crystalline structure of diamond. It’s the perfect choice for applications that require extreme wear resistance and toughness like hard turning, grooving and milling hardened steel and nickel alloys or roughing gray cast iron at high cutting speeds.
We were once called in to consult with a large automotive manufacturer that was having difficulty machining clutch plates made out of powdered metal. The part was very intricate, with a lot of internal and external diameters that needed to be turned, with some grooving and interrupted cuts. Inserts from their current supplier lasted only 20 parts before they had to be replaced. Initial tests with our CBN product immediately bumped this up to 215 parts per insert.
Polycrystalline diamond (PCD) is diamond grit that has been bonded onto a carbide substrate under high-pressure, high-temperature conditions.
It works best for abrasive non-ferrous composite material applications. Our PCD- tipped inserts (including intricate form tools), come in several extremely wear-resistant grades (so you don’t have to buy more PCD than you actually need.)
Expect a dramatic change in tool life when you switch to PCD. In our experience, the first tool life can yield savings of up to 30-50% when compared to carbide inserts.
Believe it or not, the savings don’t stop there. Frankly, PCD inserts are costly compared to their carbide relatives, so we purposefully design each of our tips so they can be brought back to life multiple times by re-grinding. This gives you hours more cutting time for your initial investment.
How the Inserts Are Made
After receiving the raw material from a supplier (usually in the form of a 63mm to 75mm diameter disc), we cut out the desired tip and shape it using an electrical discharge machine (EDM). Features and edges are ground into the tip, which is then braised onto a carbide insert body. Using this process, we can take any standard turning insert and make it the top of the line for hardness.
Edge preparation is a big part of the performance of a CBN insert. A T-Land (or chamfer)is a common edge preparation we use for CBN inserts. Prior to edge preparation, a too typically has a 90 degree corner. Edge preparation removes this sharp angle which gives the insert a beveled edge.
For example, a 20 degree chamfer results in a “strong negative” cutting angle, with a rake of 70 degrees. The advantage of a chamfered tool is that the tool lasts significantly longer than a tool with a square or “positive” edge. Most companies offer standard angles of 20, 25 and 30 degrees. If 25 isn’t right, you have to make the leap to 30. This jump would probably not give you the ideal balance between strength and accuracy required for your application. At GWS, we have proprietary equipment that allows us to go from 10-45 degree angles and everywhere in between. We are the only company that has the ability (and the will) to give our customers this level of optimal customization.
Just the Right Composition
There are only a handful of companies that sell raw CBN and PCD. While our competitors usually work with only one, we order from a group of suppliers. The reason for this is that each source has a slightly different formula that may be a better match for any one of our customers. This “pick and choose” approach gives us more flexibility to provide a superior product for different applications. If your cutting tool inserts wear out too fast, contact us for a consultation and see the difference custom can make. When it comes to our customers, we don’t make do, we make better.
Manufacturing valves, manifolds and fittings used for the delivery of ultra high purity gas for semiconductor production is a demanding job. Part of the problem is that the components are primarily made with heat resistant super alloys and stainless steel. One manufacturer came to us with a situation that is not unusual in the industry. They were experiencing poor tool life with one particular semiconductor part family. The bulk of the work was being done on either 3-axis vertical or 4-axis horizontal machining centers. Only 6-8 parts could be completed before their end mills failed or needed to be replaced. This was unacceptable.
High Standards vs. Tough Materials
The majority of projects in the semiconductor industry involve HASTELLOY® C-22® alloy (UNS N06022) and 316L stainless steel, along with some aluminum components. The problem-causing semiconductor application mentioned above involved HASTELLOY material.
This material is a well-known nickel-chromium-molybdenum blend, the chief attributes of which are resistance to both oxidizing and non-oxidizing chemicals, and protection from pitting, crevice attack, and stress corrosion cracking. Like other nickel alloys, HASTELLOY C-22 alloy is very ductile, exhibits excellent weldability, and is easily fabricated into industrial components.
On the down side, HASTELLOY C-22 alloy is generally very abrasive. It is also gummy and generates a lot of heat when machining. Ideal for semiconductor components, but not so ideal for cutting tools trying to machine it.
Setting the Bar
The situation was frustrating for a company that has a solid reputation for delivering the highest standards of quality and using the latest manufacturing technologies in order to meet strict demands for on-time delivery and value. It’s no surprise that they set about to find a partner who would meet their goal of increasing tool life.
It had already been decided to switch from a sharp corner tool to a radius corner to reduce corner edge break down. But the specifications called for a very small radius.
The search for an off-the-shelf tool that would provide longer tool life when machining their test piece led nowhere. No one seemed able to help. Then Kevin Corrigan, a representative of Deco Tool (a local distributor) suggested they bring GWS in for a consultation on a custom end mill. GWS’s ability to produce high performance purpose-built tooling quickly made getting the exact tool needed easy and virtually delay-free.
Tweaking a Standard
Our engineers took a close look at the customer’s application and realized just a few subtle enhancements to one of our standard tools would make it an excellent fit for their requirements. The tool was a 1/2″ diameter, 8-flute carbide end mill that was originally intended for titanium. But since the material was HASTELLOY C-22, we adjusted the dish angle on the tool to add rigidity and went from a non-center to a center cutting tool for improved performance in plunging operations needed to machine the “elbow.” As specified, it has a 0.0015 corner radius, which provides better tool life when compared to a sharp corner tool which was more prone to chipping. We finished off the tool with a different hone on the cutting edge for optimum cutting in HASTELLOY C-22.
Unbelievable Test Results
The customer ran two different batch tests with the new GWS tool. The first test produced 384 parts with one end mill. The second test delivered 324 parts. That accounts for the huge % increase in our headline. It was estimated that the new tool will save them $30,000 per year based on tool life alone and an estimated cost per part savings of $5.83 per part.
Aside from increasing tool life dramatically, a productivity improvement was also realized. They went from 9.6 ipm (inches per minute) to 12.9 ipm, an increase of 33%.
Similar success in their stainless steel parts yielded an additional annual savings of $20,000 not including productivity gains via higher metal removal rates in these parts as well.
The lesson to be learned from this case study is to never give up until you find a solution that will give your customers the finest parts available. Because that’s what they deserve. We work hard to be the best provider of customized cutting tools on the market. Because that’s what you deserve.
If you have a cutting tool problem that no one else can solve, contact us. We’ll find a way to save you time and money as well as increased performance.
Capital expenditures are often thought of in a negative light. After all, no organization likes to spend down their profits. But, in reality, the company that does not take the opportunity to enhance capability, create more throughput and/or to address an efficiency issue is not going to be in business for long.
One way to look at the CAPEX situation is like priming the pump. You pour money into the business to make more money in the end. To a certain extent, that is true. But at GWS, we are always on the lookout for ways to provide additional value to our customers. The purchasing of the latest manufacturing technologies is one way we accomplish this goal.
Whether it’s the purchase of a new machine tool to produce our cutting tools, or the acquisition of a whole company that is advanced in a competency we don’t currently have, all of our expenditures are executed with the intent to stay true to our “Custom Comes Standard” mission.
Scaling We focus our CAPEX planning on scaling the organization to match the needs of our customers. “Scaling” is the important word in that sentence. Creating scale within our industry is not always a seamless exercise. Like many other skilled trades, there exists a shortage of skilled labor. That means there’s not always a clear equation that says 1 person + 2 machines = $X of growth
You can generally estimate what a machining center is capable of producing within a prescribed window of time, but the spindle utilization rate achieved plays a critical role in whether or not that potential is realized.
Utilization rate is driven by presence of skilled labor, but the ability to spread the talent you have across the production floor is only possible if you work to achieve machine standardization.
Standardization Commonality of CNC equipment (both in construction and programming language), allows operators to be familiar with all the machines on the floor, not the just the ones they attend. The result is faster operations, from setup and programming, as well as maintenance and troubleshooting. This consistency allows for a flow of expertise across the workforce. The shared knowledge increases the quality of our custom-engineered tools and facilitates fast deliveries.
Inspection of our cutting tools is done the same way. Standardized inspection processes and equipment across multiple facilities gives each product the same quality signature from one shop to the next. You can be sure that the end mill you receive from Florida, the drills and reamers you get from Michigan and catalog products from Massachusetts all meet our high standards for quality.
The Automation Advantage If you want to maximize utilization of your work force, investing in automation is essential. Let’s look at this concept in action, using cutting tool grinders as an example. First of all, automation is key in quality control and JIT deliveries. And of course, it’s impossible to run 24/7 without loading/unloading robots. Automated probing tools check measurements like diameter and flute depth and make adjustments on the fly to save time and keep tools within tolerance.It also decreases downtime via manual inspection processes and limits the use of physical contact gauges, like mircometers, which can damage cutting edges.
Automatic grinding wheel changers house redundant or special tools so that a grinder can continue to run without additional setup time. This versatility, created by some judicious spending, gives us the flexibility to quickly change orders on the floor.
Meanwhile, while automation keeps the line moving, our master toolmakers can utilize their expertise in other areas more critical to our customers, like new tool design and turnkey application support.
Specialization The exception to the standardization rule would be when we are tooling up for a new customer, or a new advanced technology.
GWS will always consider the purchase of special purpose machinery and equipment to fulfill a customer’s need, (after a thoughtful and thorough cost analysis process, of course). This could be a CNC machine tool that maintains a super high tolerance or a new coating vessel to apply a special treatment. The evaluation of specialized equipment is done carefully by our engineers so that they are able to choose equipment that meets the standards of GWS and ultimately those of the customer.
When the demand for the new application grows to a certain point, we purchase more machines of the same model to invoke the standardization rule once again.
Return on Our Investment Careful investment in capital assets ensures that we put the finest technology available to work for our customers. That, in turn, means even faster turnarounds and higher levels of quality at a fair price.
But mechanics aside, our biggest investment is always in our relationship with you, our customers. We consider that to be priceless.
Contact us if you have a cutting tool problem that no one else can solve. We’ve invested in the people, hardware and software to come up with the answers.
Cutting tool breakage is a fact of life in this business. But you should be able to get your money’s worth out of them before it happens. There’s nothing like premature cutting tool breakage to get a machinist steamed. Not only is it slowing the operator down, it’s costing money. The problem is, there are a ton of variables that could be in play when a tool bites the dust before its time.
What’s to blame? Was it a bad tool? It’s not really like the old days when you could get a bad batch of carbide. It’s all reasonably good stuff today. So outside of that, what other reasons could be at fault for cutting tool breakage, chipping and inadequate performance? Let’s look at 3 of the more common mistakes.
ONE: Improper Tool Holder Assembly In order to make good parts, run out and balance are fundamental. This leads to a discussion about whether you’ve chosen the correct type of toolholder for the application (collet chuck, end mill, hydraulic, milling and heat shrink types) the correct profile of the toolholder in regards to reach, and how far your tool is hanging out. The goal of course is to minimize runout and unbalance while gripping the tool adequately with maximum rigidity in the setup. These attributes become more or less significant depending on the application. For example, balance is more critical for high speed machining operations, while gripping torque is more crucial in roughing operations where pullout is more likely.
Correct Tool Holder: As a rule of thumb, we lean towards hydraulic chucks for hole making and maybe some light milling work; mill chucks for low speed milling and roughing. For high speed machining and/or high precision work, shrink fit tool holding.
Correct Length: More times than you might think, the selection of the toolholder is an afterthought. While many operators look to achieve short stick out lengths with the cutting tool, they often overlook the gage line of the holder itself. Marrying both the correct holder type with proper cutting tool stick out are both fundamental to optimum tool performance. Save the excessively long holders for only those applications that require the reach.
Stick Out Tip– For carbide tools, look to maintain an LDR (Length to Diameter Ratio) of 6:1 or less for optimum performance. When the applications require longer, you will need to reduce cutting parameters (speeds, feeds, depths of cut) to compensate for the increased tool deflection.
Correct Profile: The shape of the tool holder and construction has a lot to do with its inherent ability to provide rigidity or reach or balance in a given application over a long period of time. For example, mill chucks generally have greater centers of mass, that when coupled with internal needle bearings, create an extremely rigid holder that dampens vibration while achieving a high degree of gripping torque. However, the balance properties of these holders are often inconsistent, making them less ideal for long reach or finish operations. Slimmer profiles, like that of shrink fit holders, enable significantly more reach (hence shorter tool LDR) while possessing ideal balance and runout properties.
TWO: The Wrong Tool/Speed for the Material When you call us with a tool life problem, probably the first things our technicians will ask is what material you are cutting followed by the speed, feed rate, radial and axial depth of cut.
If you’re running 303, 304 and 316L stainless steel, or Ti-6Al4V and other titanium alloys, you need a tool that can handle the excess heat generated at the contact edge. (See GWS Takes Aim at Gummy Materials for information about our PYSTL Series End Mills.)
A note about speed.What’s the first thing an operator does when a job doesn’t sound or look right? They turn the dial left and slow the machine down, right? It may seem counter-intuitive, but many of our tools are actually designed to run faster, not slower. This can be uncomfortable for operators who aren’t used to running at high speeds, especially if it’s a tool they are not familiar with. So, when we ask if you’re running at the right speed, we may mean you are not going fast enough to take advantage of the tool running in its sweet spot.
Machine tool and cutting tool technology have been leap-frogging for decades. A lot of operator habits developed back when cutting tools couldn’t match the total speed output of the CNC machine. Today, the learning curve has shifted back towards carbide tooling, where they are now fully capable of handling the speed and actually perform better at higher revs.
THREE: A Flawed Tool Path Five to ten flute tools (and sometimes more) can be incredibly productive when properly applied. After all, more flutes equal greater feed rates. However, you have to marry it with the right type of tool path. While more flutes translate to higher feed rates, they also translate to less chip pocket space. Therefore, to be successful with these tools requires a specific tool path that keeps percentage of total tool engagement (relative to its diameter) limited, so as not to bury it and cause breakage. The amount of tool engagement varies, but generally the more flutes you have, the more careful you need to be to ensure its not overloaded (put into a slot or sharp corner). With the right tool path, techniques like full radial trochoidal milling tool paths can be used to shred cycle times!
We have had great success with our 7-flute tool cutting titanium, but we’ve also had people break it right away because it’s very dependent on the amount of engagement (as previously stated). It’s got to be consistently light. Slotting or heavy pocketing with a 7-flute tool is not going to work. It just doesn’t have enough chip clearance within each flute. With the right tool path that keeps cutter tool engagement at around 20 percent, the tool is going to run smoothly and permit optimum metal removal rates.
If tool engagement cannot be adjusted, using 4 or 5-flute end mills may be the optimum solution, as the large chip pockets provide more forgiveness in potentially unforgiving scenarios like pockets or deep slots.
A Lot to Think About Of course, the simplest way to avoid premature cutting tool breakage is to call in the pros. Contact Us and we’ll be happy to conduct a thorough investigation of your particular application and help you optimize your process.