Toolholding 101: Top Tips for High Productivity Machining

The need for higher feed rates for high productivity machining has driven spindle speeds to levels thought impossible at the start of the modern CNC era twenty years ago.

 

Turning cutting tools faster has productivity benefits but also introduces new problems in toolholding as the physics of rotating masses become dominant. It’s just not enough to tighten a collet’s drawbar with a box wrench anymore.

 

Today, balance, form factor and multiple modes of vibration are some of the factors that must be considered if an operation needs to take advantage of the maximum performance offered by today’s machines and cutting tools.

 

Critical Tool Attributes for Good Holding

Does the cutting tool affect holding ability? More than many machinists and engineers realize. The amount of available shank for gripping is a significant factor.

 

It’s important not to forget the other factors.

 

Polished shanks reduce friction, as does the cleanliness of both the shank and tool holder. Oil and coolants reduce gripping power. Cutter shank roundness is often assumed to be close enough to perfect to ignore, but in reality a 25 millionths tolerance is necessary for high-speed performance.

 

Similarly, ISO h6 tolerance of the tool’s shank diameter is important, which for smaller tools can mean 0-6 micron repeatability. Most shops lack the ability to check low micron diameter tolerances, so a good tool supplier is essential here.

 

The Importance of Vibration

Vibration is a fact of life in dynamic systems. Whether it’s a tuning fork or an airplane fuselage, with enough energy input, multiple modes of flex will result in unwanted movement of the structure.

 

For tools spun at high speed, the problem gets worse. Centrifugal forces are set up by the imbalance of the rotating tool holder/tool assembly, which is caused by imperfect mass distribution around the spin axis. Even a set screw offset a few millimeters from center can cause a noticeable vibration at high speeds.

 

It’s a perfect storm: double the spindle speed and the forces quadruple. Since there’s no practical way to make the tool holder larger in diameter, the key to control is to minimize the offset mass. The easiest way to achieve this without dynamically balancing the assembly is to use intrinsically symmetrical tool holders.

 

Side Lock? Slow Speed Ahead

Traditional side lock end mill holders are inexpensive, quick to set up and operate, but have several disadvantages. With a TIR of .001”, poor vibration damping and weak gripping power, this traditional toolholding method is restricted to roughing operations at low speeds.

 

Shrink Fit: More Complex, But Better Performance

Shrink fitting tools would seem like the perfect toolholding technology: full contact with strong clamping forces.

 

Shrink fit tools are a good choice for moderate to heavy milling and have good speed capability, but the gripping forces are dependent on the tolerance between the tool shank and the holder inside diameter. Heavy wall holders also have superior gripping forces. Tool breakage is a frequent factor in overall shrink fit tooling costs, since broken tool shanks can’t be removed from the holder.

 

Set up time is necessarily slow with shrink fit systems as holders must be heated and cooled before use. This adds safety considerations due to burn hazards as well as the need to stock a large number of tool holders to maintain productivity.

 

Runout is five times better than side lock clamping and high-speed capability is excellent, but poor vibration damping characteristics means that the full potential of high-speed milling is limited.

 

Collet Chucks: Old Idea, Great for High Speed Machining

Most machinists start their training by screwing collet chucks into manual vertical knee mills.

 

Like a mechanical pencil, collet holding is simple, easy to understand and can generate good wedging action for strong clamping. For more sophisticated high-speed milling, however, there’s another advantage to collet-type clamping: symmetry.

 

This natural static balance helps reduce the vibration problem at high speeds, making collet chucks ideal for high feed/speed and finish milling. Compared to shrink fit clamping, tool setup is easy, fast and doesn’t require special fixtures or tools. Especially important is the runout characteristic of collet clamping: twice as good as shrink fit and 10 times better than side locking tool holders.

 

Collets are essentially a series of concentric wedges acting on the tool shank and like any wedge, the higher the applied forces, the greater the force multiplication clamping the tool.

 

Milling Chucks: All-Around Performance

For applications requiring fast tool changes combined with high grip strength, milling chucks are a good solution.

 

Milling chucks operate by cam action of multiple rows of needle bearings to apply consistent clamp forces on a collet.

 

The inclination of the needles is the key to the gripping force of a milling chuck. Like a shallow taper wedge, each element trades off fast action for a strong wedging effect. When combined with multiple elements in a multi-row needle bearing, this gives ample gripping force over a large area of a tool shank.

 

Larger tool diameters allow more needle bearing elements for even greater clamping power. High retention force combined with a simple twist-to-lock operation makes milling chucks ideal for general purpose operations. Runout, however, is reduced compared to collet chucks, but is still better than double the performance of side lock systems.

 

Hydraulic Chucks: Low Runout, Fast Tool Changing

Is there a way to combine the quick change capability of side locking systems with the excellent runout and speed of collet clamping?

 

Hydraulic clamping offers both, with the added benefit of a wider clamping range using straight collets.

 

The mechanical advantage of hydraulics offers consistent clamping force with little operator-to-operator variation and without special fixtures or tools. Hydraulics are ideal for finish milling, reaming and drilling operations.

 

Hydraulic clamping combines the best of the other methods with outstanding runout specs and is essential for precise, accurate finish work.

 

So which clamping method is ideal for your application? It depends on the most critical attributes for your operation.

 

For precise work, a low TIR may be important. For multiple setups, quick change capability may be essential for high productivity. Tool retention force may be the weak link in a tough job.

 

Which Is Best?

 

Again, it is highly task-specific and no single article can cover the full range of problems and solutions associated with advanced toolholding for high-speed milling.

 

A good tool holder manufacturer has trained personnel and technical expertise that are as important as product price and performance to high throughput shops. They’re a wealth of money saving knowledge and should be consulted for demanding jobs.

 

Learn more information about tool holder series, please do not miss the website of Shin-Yain: www.syic.com. The company provides kinds of tool holders, including shrink fit, angle head holders, boring head shank, collet holder, milling chuck, collet chuck holder, etc. Please feel free to contact or send inquiry to them. Let SYIC know your requirement of tool holders.

 

 

Article Source: https://www.engineering.com/AdvancedManufacturing/ArticleID/11710/Toolholding-101-Top-Tips-for-High-Productivity-Machining.aspx

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Advantages of Zinc Alloy Die Casting

If you’re considering aluminum die casting, there are several reasons why Zinc die casting could be a better option for you.

 

10 X’s Greater Tool Life

A Zinc die’s tooling life can be more than 10 times longer than that of an aluminum die! Lower casting temperatures for zinc are easier on tools because they create minimal thermal shock and prolong die casting tool life. With dies costing upwards of $50,000 each, having a long lasting tool can represent a significant cost savings.

 

Superior Thermal Conductivity

Zinc is a better conductor of heat than Aluminum which makes it perfect for applications like heat sinks or electrical components. This means Zinc is able to absorb and dissipate the heat better than Aluminum.

 

Low Melting Point = Cost Savings

Zinc melts at 787.2°F whereas Aluminum melts at 1,221°F. This gives Zinc an advantage because casting can use a process called “Hot Chamber” casting which is quicker as well as being less costly than “Cold Chamber” methods.

 

Faster Cycle Times = Better Pricing

Using the Hot Chamber process also gives Zinc a major advantage over Aluminum because the hot chamber process goes so much quicker than Cold Chamber. In cold chamber, Aluminum needs to be manually poured into the die either by hand or using a robot. Using hot chamber casting, the molten liquid zinc is shot into the die using a highly pressurized “plunger” which systematically shoots the zinc through the die.

 

Thinner Wall Stock

ZAMAK alloys have exceptional casting fluidity. It’s possible to cast walls in ZAMAK as thin as .25 inches. Thinner, stronger walls results in smaller and lighter products with lower costs.

 

Less Machining Required For Tight Tolerances

Zinc die casting has tighter tolerances than Aluminum or plastic die casting, which often eliminates the need for additional machining. When no additional machining is needed, it’s called “Zero Machining” manufacturing. This is one of the major advantages of Zinc die casting.

 

Superior for Decorative Finishing

ZAMAK alloys have a better surface for finishing because Zinc comes out of casting with a smoother skin. Because Aluminum has to be so much hotter than Zinc, the thermal shock from being put in a die produces a part with a surface that can be more pitted. Chrome finish amplifies every defect in a part, which makes Zinc much easier to finish compared to Aluminum. Zinc die casting parts can be easily polished, plated, painted, chromated or anodized.

 

Tough Durability

Zinc alloys are some of the strongest and toughest materials for die casting. Neither plastic, gray cast iron, nor Aluminum withstands impacts as well as Zinc alloys do.

 

If You Do Choose Aluminum

Sometime aluminum is the best choice. To learn more about aluminium die casting process or zinc alloy die casting, please visit Champion H&C Inc.

 

Champion H&C is expert of providing die casting parts and CNC machined products. If you need more information, feel free to send inquiry to let them know your requirements.

 

Article Source: http://www.brillcast.com/aluminum-die-casting.html

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Pro and Cons of Using a Malleable Iron Pipe

While malleable iron pipe fittings may sound old-fashioned next to lightweight PVC pipe, it has become valuable once more for solar heating systems, and other applications. Learn more about the pros and cons of malleable iron pipe below.

 

Pros of Malleable Iron Pipe

 

Malleable iron pipe fitting is the conduit system of choice for solar heating systems. Most solar heating systems for interior heat and hot water supplies use a dense fluid to trap solar energy. This fluid becomes much too hot for PVC pipes to tolerate, but malleable iron pipe is ideal to transport it. All the fittings of a solar heat system can be made of malleable iron pipe. Malleable iron pipe fitting is also best for cold water plumbing, as it retains its shape in the coldest conditions. Malleable iron is used for galvanized pipe fittings and can be zinc coated for rust and corrosion prevention prior to installation in a plumbing system.

 

Cons of Malleable Iron Pipe

 

Malleable iron pipe fitting without a galvanized zinc coating is unsuitable for factories and fluid transport facilities located near ocean and lake docks. It can rust and corrode on exposure to salt and other waterborne minerals. Heavy malleable iron pipe has been replaced by PVC for household plumbing.

 

If you need more information about malleable iron pipe fittings, visit the website of Golden Highope: www.golden-highope.com to find pipe fittings you need.

 

 

Article Source: https://www.doityourself.com/stry/pro-and-cons-of-using-a-malleable-iron-pipe

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Stainless Steel 430 Vs Stainless Steel 304

Stainless steel, a rust-resistant variation of ordinary steel, comes in many standard types, each identified by a number. Two, known as 430 and 304, have different properties that come from mixtures of iron and other metals in slightly different amounts. Both types have many practical industrial, medical and household applications.

 

Metals and Alloys

Stainless steel is an alloy, or combination of two or more metals, that has beneficial features not found in any of the metals by themselves. To make stainless steel, chromium is added to ordinary steel, giving it corrosion-resistant properties. Type stainless steel 430 is made up of 17 percent chromium and 0.12 percent carbon while stainless steel 304 contains 18 percent chromium and 0.08 percent carbon.

 

Magnetism, Cost and Physical Features

Raw iron is ferromagnetic, meaning you can attract it with a magnet, and you can make a magnet from it. The 430 grade stainless steel is also ferromagnetic. However, 304 is not. Type 430 steel is less expensive and is somewhat difficult to form and weld than type 304.

 

How They Are Used

Type stainless steel 430 is ideal for the production of automotive trim, the insides of clothes dryers and dishwashers. Manufacturers use stainless steel 304 in the production of kitchen sinks, counter tops, food processing equipment and other equipment regularly exposed to corrosive environments. Type 430 is one of the most popular grades of stainless steel.

 

If you have any interest in stainless steel 430 manufacturer, I recommend that you can visit the website of STANCH. The company can provide kinds of stainless steel products including stainless steel coils, stainless steel strips, stainless steel plates and more. More details, please visit STANCH Stainless Steel Co., Ltd.: www.stanch.com

 

 

Article Source: https://sciencing.com/430-vs-304-stainless-steel-7744463.html

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EDM 101: Electrical Discharge Machining Basics

Electrical discharge machining (EDM) has long been the answer for high accuracy, demanding machining applications where conventional metal removal is difficult or impossible.

 

Known by many other names, including spark machining, arc machining and (inaccurately) burning, the EDM process is conceptually very simple: an electrical current passes between an electrode and a workpiece which are separated by a dielectric liquid. The dielectric fluid acts as an electrical insulator unless enough voltage is applied to bring it to its ionization point, when it becomes an electrical conductor. The resulting spark discharge erodes the workpiece to form a desired final shape.

 

3 Types of EDM Machines

While there are many specialized forms of electrical discharge machining, industrial EDM machines are commonly grouped into three categories:

 

  • Die Sinker or “Ram” EDM
  • Wire or “Cheese Cutter” EDM
  • Hole Drilling or “Hole Popper” EDM

 

 

Die Sinker EDM

As it exists today, die sinking EDM is used to create complex cavity shapes in tool and die applications, such as metal stamping dies and plastic injection molds. The die sinker process begins with machining a graphite electrode to form a “positive” of the desired cavity. This electrode is then carefully plunged into the workpiece, causing sparking over its surface as features close the sparking gap—the distance required for sparking.

 

Wire EDM

This history of wire EDM is less clear cut than die sinker EDM, but what is known is that it was developed over roughly a decade between the 1960s and 1970s as a new method for making dies from hardened steel. As the name implies, wire EDM uses a thin wire for an electrode. The wire moves in a carefully controlled pattern, roughly analogous to a woodworker’s scroll saw, causing sparking to occur between the wire and the workpiece. Because the electrical discharge erodes by the wire and the workpiece, wire EDM machines use a spool of wire that’s continuously moving to present a fresh discharge path in the cut.

 

This “cheese cutter” approach to EDM works well, but it has an important limitation: the wire must pass entirely through the workpiece, making an essentially two-dimensional cut in a three-dimensional part. Control of the wire’s movement in an XY plane on modern-day machines is similar to other CNC-driven technologies.

 

Hole Drilling EDM

The principle benefits of EDM—its excellent surface finish, minimal heat-affected zone (HAZ) and ability to cut hardened materials and exotic alloys—make it ideal for certain hole-making applications. If a small pilot hole is pre-drilled into workpiece, wire can be threaded through it to complete the operation using wire EDM.

 

Cases where this is impossible—blind hole applications, for example—call for a specialized EDM hole making machine. Commonly called a “hole popper” this EDM drilling machine uses a rotating conductive tube for its electrode and a continuous flow of dielectric fluid (usually deionized water) to flush the cut. Hole popper EDM can also be used to create the pilot hole necessary for wire threading.

 

The ability to create accurate and precise holes, even in hardened or exotic materials has been a key development for several advanced technologies, such as EDM-created cooling holes in high-temperature alloy turbine blade sections. This permits a “film cooling” process, which allows jet engines to operate at higher temperatures for greater durability and efficiency.

 

Why Use EDM?

In practical terms, electrical discharge machining overcomes a major issue found in contact machining: hardness. In traditional processes, metal workpieces are made from special grades of hardenable tool steels machined in an anneal of soft state to facilitate cutting.

 

One the desired shape has been machined, the parts are then hardened by one or more heat treatments. This adds time, cost and can alter the finished parts’ dimensions, especially if the heat treatment process is not properly controlled. The advantage of EDM is that it can cut hardened materials and exotic alloys while also providing excellent surface finishes as a bonus. The result is often a reduced need for post-processing or surface treatment.

 

Like all machining processes, EDM requires a balancing act between speed and surface finish. In wire EDM, for example, it’s common to use faster, rougher cuts followed by finishing or skimming cuts that use a less aggressing flushing profile to minimize wire deflection. Sinker EDM sees a similar pattern, with most jobs using two electrodes: one for roughing and one for finishing.

 

“With sinkers, there’s a standing joke that you don’t want to use a sinker EDM unless you absolutely have to: If there’s no other way to get the shape you need into the part,” said Langenhorst. “Over the years, sinkers have become less and less utilized because of high-speed hard milling. As that process improved, there’s less sinker cavity work that needs to be done. The areas you can’t do with hard milling are sharp inside corners or very deep, thin ribs. That’s where sinker EDM is a must.”

 

The principle advantages of EDM are that the process is very predictable, accurate and repeatable. “All EDM machining is performed unattended, so the direct labor rate and manufacturing cost are typically lower for EDM than other methods,” said Pfluger. “In general, the EDM process is reserved for parts with smaller feature sizes and higher accuracy requirements (+/- 0.0005” or +/–0.012mm or finer accuracy).”

 

“Once you have a wire EDM in your shop, it becomes very obvious that you can do a lot more with it than just what you bought it for,” said Langenhorst. “All of a sudden, they realize that can cut strippers, knockouts, die buttons, inserts, slides, all kinds of parts. If you need to do die tryouts on a form die, you can actually cut the sheet metal blanks to test the form die.”

 

EDM & Additive Manufacturing

Anyone who’s been paying attention to manufacturing technology over the last decade or so knows there are some big changes coming. Often presented under the banner of Industry 4.0 or the fourth industrial revolution, the conjunction of various technologies, including robotics, artificial intelligence and the Industrial Internet of Things (IIoT)—will forever change the manufacturing sector, from machine tools to quality assurance.

 

Additive manufacturing is one of the most frequently cited examples of an Industry 4.0 technology, one which could potentially replace so-called subtractive processes (like EDM) entirely. Interestingly, both Langenhorst and Pfluger see additive and EDM as more complimentary than competitive, as Langenhorst explained:

 

“The biggest thing with metal additive manufacturing is that you have to build on a base plate and then separate the part from that,” he said. “Depending on the complexity of the attachment layer, it can be a pain to separate them. People have tried bandsaws, grinding, slitting wheels and all different kinds of things, and we’ve done quite well cutting the parts off the base plates using wire EDM. Obviously, it takes a submerged machine to do that, and in some cases you get this honeycomb structure between the workpiece and the baseplate that acts as a heatsink; if you don’t build that just right, it can trap powder, which really raises hell on the controls for an adaptive wire EDM machine.”

 

Pfluger agreed, adding that “Sinker EDM is also commonly used to finish certain features on additively manufactured components, such as small features that require high accuracy and finer surface finishes than what can be produced by additive manufacturing.”

 

“We’re even trying to figure out how to create a less-expensive wire EDM machine to be used specifically for separating additively built workpieces from their baseplates, so basically an electric bandsaw,” Langenhorst added.

 

Is Electrical Discharge Machining Right for You?

If you need to rough cut a lot of parts quickly, electrical discharge machining probably isn’t the right process for you. (It should be noted that Langenhorst did point out that you can use wire EDM to cut shims by stacking the stock, sandwiching it between two pieces of quarter-inch steel, and cutting off a stack.) However, if you’re looking for a machining process that’s accurate, precise and stress-free—at least on the workpiece—EDM could be just what you need.

 

If you need more information about EDM machines, I recommend 2 companies to you – they are Excetek Technologies Co., Ltd. and Ocean Technologies Co., Ltd.

 

Both of them are specializing in manufacturing various electrical discharge machines including wire cutting EDM machines, die sinking EDM machines, hole drilling EDM machines, etc. Try to visit their website to get the details you need.

 

 

Article Source: https://www.engineering.com/AdvancedManufacturing/ArticleID/10100/EDM-101-Electrical-Discharge-Machining-Basics.aspx

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3 Must Have Woodworking Machines for Every Workshop

If you are an aspiring woodworker, who wants to take up woodworking professionally you should give ample thoughts to buying essential woodworking machines that you will need to carry out woodworking projects efficiently. Just like any other craft, woodworking begins with mastering the basic skills and knowledge to use the fundamental tools efficiently. Of course, a lot depends on the kind of projects you want to take up. But make sure that you invest in the essential woodworking machinery gradually. This way you will be able to assess if you really need a particular machine or not. As you gain more experience in the field, you will be able to find more specialized tools that allows you to do more things efficiently.

 

In this article we will not discuss about the basic hand tools that you will need to get started in woodworking, rather we will concentrate on choosing the power woodworking tools, which will take your woodworking experience to a whole new level. The first three woodworking machinery, that we would recommend any aspiring woodworker are: a table saw, a portable planer and a plunge router. With these, you will be able to carry out a number of tasks, right from milling, joinery and shaping.

 

These Three Different Pieces Of Woodworking Machinery Are Very Important:

 

  1. The Table Saw:

 

A table saw is at the heart of every woodworking workshop. There are several reasons why it has that coveted place among the woodworking machinery you have in the workshop– it not only allows great precision in ripping a stock in straight lines but is also useful in cutting it at various angles. It does the basic milling of a stock with ease and is well suited for joinery works.

 

When choosing a table saw, there are a number of factors that you need to consider. The first thing you need to understand is that – it is going to be one of the most used machinery in your workshop, so you must always buy a quality one. The work surface of the table saw should be rigid and strong, and should be able to sail through all types of projects. Ideally, you should buy one that has a handle to raise and lower the blade easily, and another handle that will enable you to adjust the angle of the blade. Another essential feature that it must have is the connection for dust collector. It should have powerful motor that will let you cut through hard wood and make deep cuts. The blades of the table saw are incredibly sharp, so they should come with a blade guard and a power switch that is within easy reach while working on it. Many table saw today come with a paddle switch that can be pressed with your knee or foot if you need to shut it down in an emergency.

 

  1. The Surface Planer:

 

A surface planer is another indispensable woodworking machinery to have in a woodworking workshop. It can help you to be incredibly creative in the work you do by smoothing any rough saw stock to your desired thickness. Gone are the days when a stock was hand planed tirelessly to get the designed thickness and smoothness, a surface planer can help you get the same result in a short time. Typically, a planer has a table of the dimension between 10” to 14” on which you can feed your stock. There are a set of blades that rotates, thereby cutting the wood as it is fed through it. You can adjust the depth of the cut b using the crank at one end of the planer.

 

Another important feature that you should consider having in your surface planer is a dust vacuum. This machine generates a lot of dust, so having a dust collection system in place with lengthen its life. This machine is quite noisy when it is at work, so always wear hearing protection when you are using it. If not used with care, it can be dangerous too. So, adhering to the safety precautions is of prime importance.

 

  1. The Router:

 

Every professional woodworking will have a router in his workshop. It is one of those wondrous pieces of woodworking machinery that can carry out a number of tasks for you – not only trimming and decorative edge treatments but also various joints like mortises, rabbets, and dadoes. By having a router in your workshop, you are adding versatility in your woodwork. By making use of patterns, you can create identical parts from wood.

 

A router makes use of various bits to produce a number of shapes. For beginners, a stationary base router is good enough. It will help you make cuts at a depth you make before making a cut. For advanced woodworkers, a plunge router can add a creative touch to the work. The plunge router bites into the wood, makes the cut and then allows you to lift it back. When choosing a router, choose one that is at least 2 HP or it won’t be powerful enough to carry out various tasks for you. You should also choose one that comes with variable speed. Collet size is another feature to consider. It is important if you want to use various bit sizes. It is important to remember that smaller bit can be put into larger collet size but not vice versa. The power should be within the reach of your fingers, and you should not need to take your hands off the router to switch it on or off.

 

Other than these 3 woodworking machinery, there are a few other power tools that you can consider buying. One is a good jigsaw. It is a very useful tool that can help you in varied tasks like cutting curves. When buying one look out for one that comes with blade guides as it will help in keeping the deflection of the blades to a minimum. Apart from that a handheld drill and a quality random orbit sander with a provision for dust collection are great power tools to have in your arsenal. Quality of these tools should always be of prime importance when choosing these tools and one should always remember to adhere to the safety norms while using them.

 

Learn more information about woodworking machines, try to visit TRUPRO-TEC: www.trupro-machine.com. The professional manufacturer of metalworking machines, woodworking machines, and metal forming machines etc.

 

 

Article Source: https://www.mikeswoodworkingprojects.com/3-must-woodworking-machinery-every-workshop/

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Buying a VMC: Considering Toolchanger, Coolant Delivery and Chip Removal

Among characteristics like structure and spindle quality, here are a few factors to consider when buying a vertical machining center.

 

Whether it’s for a toolroom, a job shop or a production house, there are a lot of factors to consider when it comes to acquiring a vertical machining center (VMC). Key preliminary considerations include the intended application and workpiece(s) and the needs of a shop’s various departments. And then there’s the research and data-gathering process.

 

In addition to characteristics like structure and stability and spindle details, potential VMC buyers should keep in mind how the toolchanger, coolant delivery and chip disposal systems contribute to overall machine efficacy.

 

Selecting the Toolchanger

 

The toolchanger specified for a new VMC must have an adequate number of tooling pockets and be able to accommodate the size and weight of the cutting tool assemblies. Every VMC has a maximum tool weight and diameter that its toolchanger can handle to prevent a tool from dropping out of the pocket.

 

In high-production environments, where many tools may be required to machine the parts, tool-change time can have a substantial influence on efficiency. For example, having a machine capable of a 1.4-second chip-to-chip tool-change time, rather than 3.6 seconds, can quickly add up to more productivity and profit.

 

Coolant Concerns

 

For certain applications, optional provisions for delivering coolant at high pressure directly through the spindle are recommended. Coolant pressure as high as 1,000 psi is intended to promote chip evacuation from deep bores in which chip breaking is directed at the tool point. Unlike time-consuming peck-drilling cycles, through-the-tool, high-pressure coolant enables the material to be removed in one pass. This approach may reduce drilling time by as much as 30 percent. Additionally, the part remains cooler, surface finishes inside the bores are protected, accuracy of the parts is maintained and cutting tools last longer.

 

For high-pressure coolant, the capacity of the coolant tank may need to be enlarged. Likewise, an oil skimmer may be an option to consider for extracting waste oil from water-soluble coolant.

 

Chip Removal

 

Chip removal is an important consideration that is often overlooked in the evaluation of a new CNC machine. Whether chips are evacuated from the machining zone with water, oil or air jets, they will fall to the bottom of the machine. A smaller volume of chips can be removed by an auger, which is typically standard on most VMCs, but a large volume of chips may require a conveyor. Although it is possible to have the machine operator manually remove chips from the machine, this task is labor-intensive and messy. Using a chip auger or conveyor to remove chips automatically and deposit them in an external bin is recommended. Pay attention to whether the chip conveyor or auger evacuates the chips from the side or rear of the machine, however. The location of the chute determines how much space will be needed on the shop floor, how close the machine can be placed to other machines or walls, and how easily a fork truck can retrieve a loaded chip bin.

 

If you need more information about vertical machining center, I recommend that you can visit the website of Vision Wide.

 

Vision Wide Tech is a professional and experience vertical machining centers manufacturer based in Taiwan. If you are looking for high efficient, high accuracy and durable vertical central machinery or other machining centers, you can count on them. Visit Vision Wide: www.visionwide-tech.com to get more details.

 

By the way, if you are also looking for coolant, you can visit the website of Min June Hong. The company is the reliable lubricant and oil manufacturer in Taiwan. Learn more details about coolant series, try to click here: www.maxlubeoil.com

 

Related Article:

 

Article Source: https://www.mmsonline.com/blog/post/buying-a-vmc-considering-toolchanger-coolant-delivery-and-chip-removal

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Your Best Coil Slitting Machine Choice – Overview and Advantages of Slitters

The Advantages of Slitting Line

 

High quality slitting requires very stiff and well-designed slitter heads with zero axial gaps, absolute parallelism of the shafts on rotation, minimum shafts bending, combined with the right choice of tension device, able to provide high tension to the slits without any marks on the surfaces or on the edges of the processed material.

 

The slitting lines are probably the equipment which require the highest degree of operator attention and skill due to the fact that a large number of slits are handled at the same time for feeding and evacuation and also the different tools set ups must be prepared in advance by the operators in a very fast and accurate way. Therefore all the auxiliary items around the line which facilitate those operations reducing down times are of crucial importance for a properly designed slitting line.

 

If You Need More Information about Slitters, I Recommend This Company –

 

MAY SHUAY Technology Co., Ltd. specializes in manufacturing and marketing of high efficient and labor-saving welding equipment and coil slitting machine. They are always committed to helping our clients achieve the production goals by supplying the most productive, flexible, reliable and safe coil slitting line available.

 

Coil Straightener (Slitting) Cutting to Length Line is mainly composed of uncoiler, feeder and slitter. The function of coil slitter & straightener machinery is to slit a wide coil to stated width strips coil along with the length direction which can be used for milling, welding pipe, coil blend forming, stamping as billet.
Coil Straightener (Slitting) Cutting to Length Line

Feature:

  • Uncoiler: Uncoiler has up to 1250mm width and handles coils up to 7,000 kgs. Uncolier can have hydraulic expansion and can be motorized according to the requirements of the customer.
  • Coil Leveling: This is the process of removing coil set or cross bow out of flat rolled material or steel sheet. The material is run through an entry and exit set of bride rolls, with the corrective leveler in between.
  • Coil Slitting: Line speed of the slitting lines can go up to high mpm and coil weight can achieve to 7 tons. Coil slitting lines are suitable for end users and service centers.

 

Application:

Milling, Welding pipe, Coil bends forming.

 

Get further details about coil slitting machine, please visit May Shuay: www.seam-welder.com

 

 

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Buying a VMC: The Basics of Spindle Speeds and Tapers

What’s the difference between CAT, BT and HSK tapers? These and other questions are important when considering a new vertical machining center.

 

Whether it’s for a toolroom, a job shop or a production house, there are a lot of factors to consider when it comes to acquiring a vertical machining center (VMC). Key preliminary considerations include the intended application and workpiece(s) and the needs of a shop’s various departments. And then there’s the research and data-gathering process.

 

In addition to characteristics like structure and stability, potential VMC buyers should be aware of machine spindle considerations.

 

Spindle Speeds, Torque and Horsepower

 

Selecting a machine with the appropriate range of spindle speeds is a critical consideration. The trends in recent years have been toward coated tooling, smaller tools, shallower depths of cut and higher feed rates. Smaller tools require a higher spindle speed. Faster feeds and speeds deliver better surface finishes. High-speed machining requires less spindle horsepower and torque (twisting force) when taking smaller cuts.

 

In contrast, large-diameter tools such as face milling cutters typically use slower spindle speeds and take deeper cuts to remove larger amounts of material. However, this mode may require greater machine rigidity. Moreover, large tools generally require more horsepower and torque. In addition, large-diameter taps must run at lower rotations per minute (rpm), which calls for higher torque. Alternatively, thread milling can be done at higher speeds, (nearly the same feeds and speeds as a regular end mill), thus requiring less torque. Charts are provided by all machine builders to show the available spindle torque in relation to horsepower and spindle speed. Study them closely.

 

CAT, BT and HSK

 

After selecting the spindle that best meets the horsepower, spindle speed and torque requirements comes selecting the type or style of tooling taper and its size. Tooling taper refers to the peculiar cone shape of the portion of a tool holder that fits inside the opening of the spindle. Every spindle is designed to accept a certain standardized taper style and size. Other styles or sizes cannot be used. Three taper styles are primarily used today: CAT, BT and HSK. The specifications for these tapers are governed by national and international standards.

 

CAT and BT tooling are referred to as V-flange holders, and are the most widely accepted standard for milling in the United States. The BT metric series is the Japanese equivalent and is prevalent overseas, particularly in Europe, where it was originally developed. Both BT and CAT tool holders require a retention knob or pull stud to be secured within the machine spindle.

 

HSK is a German standard meaning “hollow shank taper.” The tapered portion of the holder is much shorter and it engages the spindle in a different manner by using no pull stud or retention knob. The HSK holder was developed to provide greater repeatability and longer tool life, especially in high-speed machining applications.

 

There are limitations and advantages to using any of the three tooling types. Price, availability, accuracy and repeatability vary from style to style. The proper selection is usually based on the application.

 

Selecting the Spindle Taper Size

 

The size of the spindle taper and the corresponding shank taper has much to do with the weight and length of the tools being used and the amount of material to be removed. Although CAT40 is the most commonly used size in the United States, if you already own, say, the equivalent 300 BT30 shanks in your shop, there would be little or no advantage to selecting a CAT40 spindle in a new machine. If you plan to use 3-inch-diameter or larger cutters, take deep cuts, or use tools that are more than 20 inches long, a CAT50 taper would probably be best. Using a holder of this size for heavy or long tools helps prevent excessive side loads on the spindle bearings. (This problem is more common with horizontal machines on which tool droop can add to unwanted forces.)

 

If you need more information about vertical machining center and tool holder series, there are two companies that I recommend to you. They are:

 

SEHO Industry Co., Ltd. is the ideal source for full series of CNC machining centers, whether you need vertical machining center or horizontal machining center. You can find new and used CNC machinery on their website. Visit SEHO: www.sehoworld.com to get your ideal VMCs.

 

Shin-Yain Industrial Co., Ltd. is the professional tool holders manufacturer in Taiwan. You can find CAT, BT and HSK tool holders on their website. Learn more information about tool holders, please do not hesitate to check out SYIC’s website here: www.syic.com

 

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Buying a VMC: Considering Structure and Stability

Design and construction govern a vertical machining center’s ability to machine parts to tight tolerances with accuracy and repeatability.

 

Whether it’s for a toolroom, a job shop or a production house, there are a lot of factors to consider when it comes to acquiring a vertical machining center (VMC). Key preliminary considerations include the intended application and workpiece(s) and the needs of a shop’s various departments. And then there’s the research and data-gathering process.

 

Among the numerous machine tool characteristics to scrutinize before buying a VMC are machine structure and stability.

 

Accuracy and Repeatability

The ability to machine parts to a tight tolerance and to do so time after time must be considered. That is where a machine’s design and construction come into play. Its ability to achieve the required precision and accuracy, and the number of parts to be machined, will influence the quality of machine that’s needed and the price it will demand. The higher the accuracy and the larger the quantity of parts to be produced, the higher the price tag the buyer can expect.

 

Because of the characteristics of a C-frame design, a VMC’s thermal stability can be a challenge. Just as a sturdy house requires a solid foundation, the same is true for a stable machine tool. Most superior vertical machining center structures are engineered using finite element analysis (FEA) software. It’s not simply the weight of the machine that matters; it’s also its design and the placement of the weight that determines its rigidity and stability.

 

Accuracy and repeatability must be designed and built into the machine, regardless of its price. Some are equipped with large ballscrews and a different pitch to enhance accuracy. Laser and ballbar calibration can be used to ensure better part accuracy, but only up to a point. A poorly designed machine will never consistently produce high-accuracy parts.

 

Thermal Growth and Components That Counter It

Machine stability is primarily affected by thermal growth. Spindles generate heat, as do ballscrews, machine tables and guideway systems. In addition, the faster a machine moves, the more friction and heat it generates. This heat contributes significantly to changes in the size and position of machine components, causing a machine to “grow” or distort and the location of the spindle nose or tool point to move unpredictably. Because of these shifts, one of the biggest challenges of five-axis machining is the inability of the control system to calculate the exact position of axis pivot points at all times.

 

To combat this heat and the unwanted growth it causes, chillers are used to cool ballscrews and control the temperature of spindles and spindle housings. Thermal sensors that measure and automatically counteract machine growth are located at key points on the machine. These provisions are especially critical in die/mold applications in which longer machining times allow more heat to accumulate. Left uncontrolled, thermal distortion in the machine can result in unacceptable errors in the shape of the finished mold. It may not be possible to correct these errors.

 

High-end machines usually employ scale systems on each axis rather than the standard encoder feedback systems supplied with most vertical machining centers. Anti-backlash systems are often engineered into the ballscrew nut to improve machine repeatability. Likewise, certain guideway systems are designed for high-speed, low-friction operation to help control thermal growth. Of course, all of these special features come with a price. High-performance VMC spindles can range in price from $4,000 to $30,000. There is a big difference in design between a “value-priced” $50,000 machine and a high-end VMC with a $300,000 price tag. That said, if accuracy requirements aren’t especially tight and if part quantities are manageable, then the value-priced machine may suffice. Know what you need!

 

A Firm Foundation

A machine’s foundation and placement on the shop floor can greatly affect performance. Although it may be OK simply to set commodity machines on an existing concrete or wood floor, machining at high rates with rapid axis acceleration may require the machine to be tied down so it doesn’t “walk” across the floor. Heavy depths of cut on some materials also may cause excessive vibration, requiring the machine to be securely anchored to the floor. In some cases, it may be necessary to install a steel-reinforced concrete base that is isolated from the surrounding floor.

 

It’s important to note that a machine should never be located over a joint or crack in an existing concrete floor. The uneven support will make it impossible for the machine to perform accurately.

 

Jiuh Yeh, a Taiwan manufacturer, has carried metal cutting solutions for the difficulties confronting all businesses. The arrangements that take after are consolidated into almost every part of the daily life and they are heavily applied from aviation to nourishment preparing, medical to mining, transportation to energy, and much more. If you need more information about vertical machining center and other excellent machinery, try to visit Jiuh Yeh: www.jiuhyeh.com

 

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