If you talk to the common man on the street, they may know very little about CNC, CNC accesories, and how we need them for every day life. Little do they know that the CNC process will have already touched their life in one way or another. If you work in manufacturing then you will have heard of the term CNC and you’ll most likely have dealt with CNC machines and CNC accesoires at some point. Everything that an operator can do with conventional machine tools is programmable with a modern CNC machine. Next we take a closer look at CNC machines and their operations. Comuter Numerical Control is the future for all businesses, and traditonal manual machines are being seen less and less.
CNC Accesories : Accuracy and Efficiency
CNC is the best way to make precision parts. It can do so effectively, and efficiently, and with the greatest levels of accuract. A CNC machine is easy to keep up and running upon initial setup and requires only some preventative maintenance that you can often carry out yourself . Even the work piece loading process is automated in the most modern CNC shops with CNC accesories allowing for virtually no human presence on the factory floor.CNC operators are required to complete other tasks related to the operations of the CNC and these can include the maintenance of machines. Other tasks will include measuring work pieces and making necessary adjustments to keep the machine running always at maximum efficiency.
If a CNC could only move a work piece in two axes functionality would be severely limited. This is why almost all modern CNC machines are programmed to operate in several other ways. The days of 2 axis machining are virtually obsolete, and modern machines now commonly work on 5 or more axes. The actual machine type also has to do with its programmable accessories as well. Some of these accessories would include the following. An automatic tool changer that allows the tool to be automatically placed in the spindle when machining and therefore making production time quicker as a machinist is not required for the changing of tools. The speed of the spindle can easily be specified from a remote computer and the spindle can be turned in two directions. In addition many machining operations must have coolant for lubrication and the levels of such should be checked frequently.
With CNC touching so many aspects of manufacturing and larger factory fabrication, almost all machining processes now incorporate the use of CNC. If we take a look at how CNC machining affects the world of metal removal and metal fabrication, we will see just how important CNC is. All the processes of facing, boring, turning, grooving, knurling, and threading that are involved in metal production are done with CNC turning centres. There are many variaties of these machines which include, CNC milling machines, CNC drilling and tapping centers, and CNC lathes.
When using CNC in association to metal fabrication, let’s take an example think of a metal filing cabinet. All of the initial components are made of steel sheets of metal. These sheets are sheared to a certain size, and after this holes are placed in specific locations. The sheets are then formed to their final shapes by CNC machines.CNC machines are allso used for laser cutting, friction and ultrasonic welding, plasma cutting, fabric cutting, routing and even sawing.
Most manufacturers, both small and large scale ones have been continuously providing end products to consumers. This involves a series of processes including producing and assembling of different components. In order to be able to continue doing so, it is essential that you have a reliable source for your parts. Due to high product demands, manufacturers have to minimize their product turnaround time. This is necessary in order to supply sufficient products to their distributors or directly to their consumers. The most common method is to outsource specific tasks to specific companies. Outsourcing to a local CNC machine shop is far better than outsourcing abroad. You will not create a weak link in the supply chain, and your customers will continue to be satisfied.
CNC Machine Shop : For Milling, Turning, and More
When it comes to producing certain components involving CNC milling operations, most manufacturers or businesses would opt for CNC Machine shops. Similarly if your business requires parts production, this would be the best choice. Here are a few reasons that you should start looking for CNC machine shops to perform such task. Remember that a local machine shop is the best for your Bristol-based business. When you use CAM Machine, you will be supporting local businesses whilst getting the very best grade of machined parts.
When you choose to use a CNC machine shop you will reduce overhead cost of your business operations. You can save much in parts production cost as you do not need to purchase any CNC milling machines. As these machines require maintenance over a long period of time, you do not need to pay any maintenance fees and costswhen the parts production tasks are performed by reputable CNC machine shops. Not having to maintain your own machinery will allow you to really cut back on your monthly overheads. Also you will no longer need to hire operators, or pay for training.
When you choose a CNC machine shop, your parts will be made with professional expertise. Normally, a reputable CNC machine shop perform CNC milling operations based your designs or prototypes. For instance, if you have a prototype or a design in form of CAD design, they will provide a consultation service. This will be directed to their engineers who are responsible to give professional advice about your design. This also ensures that the customized parts production is workable based on your preferences.
A machine shop will have the most up to date macines that can perform repetitive cutting and drilling operations precisely. If you are in need of these specific components to be produced on a regularly basis and quickly, CNC machine shops perform parts production tasks by using high precise CNC milling machines. In addition, these machines are capable of producing components in a large scale without neglecting accuracy and precision. Apart than that, you can also rely on these shops to carry out complex parts production as they provide CAD/CAM machining for 3D complex components.
When you outsource your needs, you may also be able to reduce unwanted wastage. If your business has lack of production tools that could not machine high precision parts, you would most likelyhave a high production cost due to unnecessary wastage. As mentioned early, most CNC shops operate high precision CNC milling machines which are known to manufacturecomplex parts precisely,reducing wastage effectively.
Most shops provide additional precision machining services. In order to provide more CNC solutions to clients, most shops provide additional services like CNC turning, spark erosion as well as additional treatments like hardening, plating, anodizing and powder coating. All of these are generally offered with affordable rates. Therefore, you can request for a quotation from these CNC machine shops if you are interested in some of their additional services.
A vertical CNC milling machine is a machines that operates with vertically oriented tools. Most of the operations include drilling and milling with the help of CNC or Computer Numerically Operated machines. It is efficient in completing jobs which include drilling, planing, profile contouring, slot and keyway cutting. As these equipments are controlled by computers and CNC, they are known to be precise and accurate in cutting, drilling and other such procedures. It includes multi-dimensional work planes that move both the work piece and the cutting head simultaneously. This type of advances milling and drilling can be seen in CNC workshops across the UK.
Vertical CNC Milling Machine : Features of Modern CNC Machines
The spindle axis in a vertical mill is oriented in a vertical position. Spindles are used to hold the cutters and it rotates on the axis of the spindles. It is easy to drill and cut with these equipments as the spindles can be extended according to work requisites. There are basically two types of vertical equipments which include the turret and bed mill. The turret mill includes a stationary spindle axis. For the process of cutting, the table of the equipment is moved parallel and perpendicular to the axis of the spindle.
These equipments have quills with which the cutters can be lowered and raised. This allows for an extensive amount of different cuts to be made. Working on more axes than older and more traditional machines, a modern vertical CNC milling machine is capable of making extremely precise cuts and in turn CNC parts. Now let’s take a look at a bed mill.
In the bed mill the table of the equipment moves only vertical to the axis of the spindle. Large equipments are usually of the bed variety as it is easier to operate than the turret machines. The turret machines are versatile but if the size of the equipment is large, it requires considerable effort and time to use it efficiently. This means that for a production line that is quick, it is necessary to use a bed mill.
Another type of vertical CNC milling machine is a drill press. The drill press is the most common variety of cnc milling machine. The entire drilling process is completed with the help of this equipment as the tool bit remains static in the drill press. The vertical movement of the equipment is essential for the process of drilling. There are semi-operated, fully automated, semi-automated equipments among the Computer Numerically Controlled equipments.
Both the work-piece and the tool on these equipments are driven and controlled by computers. These computers operate on the basis of CAD files which include the programs necessary to move the tools during the operational procedures. Working on CAD files that have previously been loaded into the CNC computer, error is virtually non-existent. CNC allows for quicker and more accurate drilling and cutting, and is virtually replacing manual machines on the factory floor.
The functions of the CNC milling machine begin with a comprehensive drawing which is produced by the one of the CAD programs. This specific drawing includes all necessary details relating to the work-piece. The base of the program requires informative details about the profile and dimension of the work-piece. The program also includes varied information such as machining sequences, different types of tools used, and the speed of the tools, the physical dimension of the work-piece and the start and end points.
As the entire process of machining is controlled by the computer, it requires less human intervention and effort. One of the greatest advantages of these machines includes its incomparable efficiency and accuracy in the process of drilling and machining. It can be used to complete a wide variety of operations which include the template drilling, boring and reaming, face and contour grinding, slot and keyway cutting and so forth.
CNC milling and turning are evolving every day. A far cry from the basic machines of the past, a modern vertical cnc milling machine will work on many axes. This allows for so much more to be possible from one machine. CAD and CNC ensure that there is no room for error, and that the speed for production of parts is faster than ever before.
In this article we are going to take a look at the difference between lathes and turning centres. When it comes to CNC turning programming, the two terms are often used interchangeably. In fact, there really is not formal distinction between the two. What is clear however is that a lathe is a more simple machine, and therefore the operations are simpler. Lathes were invented long before modern day CNC turning centres. A modern day turning centre will integrate both milling and drilling capabilities.
CNC Turning Programming : CNC Lathes
A simple CNC lathe works on 2 axes, X and Z. It typically has only one chuck. A turning centre however will incorporate the Y axis. A turning centre is therefore more of a multi-tasking machine. What this means simply is that they offer far more than turning, which is where the limitations lie with a basic CNC lathe. The CNC lathe can therefore be seen to have evolved into the modern day CNC turning centre we see today. However, whether you are working on a lathe or a complex turning centre, the basic of CNC turning programming stays the same.
The headstock houses the speed and gear changing mechanics, as well as the main spindle. In the early days, the spindle was driven directly via a flat belt pulley. Times have changed however, and nowadays it is driven by an electric motor. Connected to the headstock you will find the lathe bed. They are connected in such a way so that the carriage and tailstock move in parallel to the spindle access.
Leadscrews and Feedscrews
The feedscrew can be summarized as a long driveshaft. It connects to a series of gears that allow the carriage to be driven along the Z axis. The leadscrew on the other hand does the same thing, but along the X axis. Both of the above can be found made to metric or imperial standards. The carriage is what holds the tool in place, moving the cutting tool longitudinally or perpendicularly. The carriage is made up of the saddle, and the apron, these casting being found on the top and the side, respectively.
In CNC turning programming you will find a wide variety of operations that are performed. The amount of different operations will depend on whether you are working on an old-fashioned lathe or a modern turning centre. Operations include facing, knurling, threading, drilling, boring, reaming, and taper turning.
Configuration of your Turning Centre
Nowadays you will find two different types of CNC machining centres. Traditional they would be horizontal, but nowadays you will also find vertical turning centres. Horizontal centre still make up around of all turning centres found.
When it comes to CNC turning programming it can therefore be said that a lathe and a turning centre are basically the same thing. But, a lathe is limited to the parts that it can make due to the fact that it works on only 2 axes instead of 3.
When designing custom CNC machined parts Bristol, there are some practices you need to keep in mind. To be successful at making CNC machined parts you need to be able to use CAD/CAM software. The CAD model is loaded into CAM software, creating tool paths that are based on geometry. Complex shapes can be made by using 5 axis CNC milling machines. Unlike a CNC lathe where the tools are stationary, a milling machine turns whilst the stock is fixed.
The X, Y and Z axes can all move simultaneously, producing a wide range of features from simple lines to the most complex geometrical shapes. Limitations do exist, but these are constantly becoming fewer with the advances in technology.
CNC Machined Parts Bristol : Tolerances
Tolerances may be set as default or provided with the specification for making the part in question. Tolerance is the acceptable range for a given dimension. The tighter the tolerance, the higher the cost for making the CNC machined parts. Longer cycle times will also put up the cost of making custom parts. Tighter tolerances should therefore only be used when absolutely necessary and when they have been specified by the client.
Size Limitations and Material
When using a milling machine, the part size will be limited to the capabilities of the machine that is being used. The capabilities of a lathe will also depend on the build space. The material you use for making custom CNC machined parts should also be carefully selected. Some things that should be taken into consideration are the rigidity, the hardness, and the chemical and heat resistance of the material.
When the parts required are metal, softer metals are quicker to machine and will provide rapid results. Harder metals will be used with slower machine speeds, putting up the cost quite dramatically due to the timescale needed to complete the order of machined parts. Plastic materials are a cheaper alternative to metals, such a polyethylene.
The more complex the parts required, the longer it will take. Setup time will be increases, and the workpiece will be contoured on multiple faces. To create a complex surface that has a very smooth finish, very small cuts are required. This once again puts up the price of the parts due to the time taken to complete them.
These are just some practices that you need to take into consideration when completing orders for custom CNC machined parts Bristol. The more complex the design, the longer it will take. If you have a 5 axis machine for milling this will greatly speed up the process. Although investing in a 5 axis machine may seem costly at the outset, it will greatly reduce production times. It will also allow for delivery of far better quality parts. What this means is that investing in a 5 axis machine may be costly in the outset but it is a worthwhile investment that will allow you to produce higher quality parts more quickly.
CNC milling tools for cutting come in a range of materials, sizes, and types. When trying to achieve a detailed model it is generally more efficient to use a combination of several different toolpaths. A larger tool can often achieve better results than a small tool that has only a small stepover. In this article we are going to look at the different types of CNC milling tools used for cutting.
CNC Milling Tools : End Milling
When using end milling, the cutter will normally rotate on the axis that is found vertical to the workpiece. Teeth on the cutting tool will be on both the periphery as well as the end face of the cutter. If the surface of the workpiece to be cut is complex, a ball nose end mill is often used. This is also known as a spherical end mill or ball end mill. The type of tools you need is determined by the characteristics of the workpiece you wish to achieve. End mills are generally used for rough cutting and cutting in 2D; finishing and V-bit operations are then carried out by ball nose cutters.
When discussing CNC milling machine tools it is also important to understand the end geometry. Cuts can be up or down, or compression cuts. The cuts will vary depending on the number of flutes used. End mills are generally intended to only cut horizontally. Up cutting will result in the chips being ejected upwards; down cutting, downwards. A compression end mill will ensure a smooth surface on both the top and the bottom.
Like CNC milling machine tools, end mills also come in a large variety of shapes. The most common of these are the ball end and flat end mills we have already discussed. A model can be successfully tooled using a combination of ball end and flat mills. If only one tool is to be used for the model a ball end is recommended as it will achieve a smoother finish.
Choosing a Ball End Mill
When you have a choice of ball end mills, always select the large size that is available. A larger tool will leave smaller scallops for the same stepover. What this means is that the finished model will be smoother and of a higher quality. Small tools should only be used when required for cutting out detailed areas. Larger tools also have larger clearance, cutting more smoothly, and staying sharp for longer.
The stepover is the distance that any tool moves over between passes. The stepover value will therefore determine whether or not a model has a smooth finish, or if tooling marks are visible. The smaller the stepover, the longer the tool will take to cut. The stepdown is the depth with which a tool can cut with one operation. A maximum stepdown is only ever used when the material being cut is smooth. When the material being cut is harder, a smaller stepdown value is required.
Although the number can vary, it is most common to find two flutes. Some projects however may benefit from other flute geometry that is not the norm. These include contour cutting of MDF sheets. A single flue will allow for larger chiploads where softer materials are used. When the workpiece is harder, a double flute is generally used. The number of flutes can be expanded to more than two, and this will give an even better finish to harder workpieces.
The more cutting edges you have, the higher the feed rate achievable. This should prevent premature tool dulling and burning. The more flutes used with your cnc milling machine tools, the better the surface finish. The most common used combinations are two and four flutes. Four flutes are used when a better surface finish is required.
Choosing your End Mill
End mills are made of a variety of materials, commonly cobalt steel alloy or tungsten carbide. The latter of these options for your CNC milling tools is more rigid and therefore more resistant. Carbide downs however have a brittle nature; this means that you need high rigidity to prevent tool breakage. The cutters you choose may be further coated with titanium aluminum nitride or other ceramics. The most common coating you find is one that is bluish grey in colour and by reducing friction and improving hardness, can boost speed by up to 20%.
A micro CNC milling machine is like any other, except that everything is scaled down. What is not scaled down however is the level of accuracy and precision you can achieve. So, how do you scale down your own milling techniques and ensure that you are successful and produce parts that are of the highest caliber?
Accuracy is a must with your micro CNC milling machine. As features begin with around 0.001 of an inch, you can easily see why accuracies of 0.0001 of an inch are required. To ensure this accuracy, you will need minimal runout. In fact, runout is akin to accuracy. What is required here to ensure levels of accuracy is that the cutting flute is placed exactly where it need to be along the rotating axis of the spindle. If you have too much runout, then some flutes will go on to do more work than others, and deeper cuts may be seen. This should not be allowed when micro milling, as the fragile cutters cannot tolerate a large chipload.
Micro CNC Milling Machine : Cutting Force and Care for Deflection
When you are using a micro milling machine, the smaller tools will deflect more easily, the forces being used being up to 20 times greater than with a traditional machine. To maximize rigidity, you should always use the shortest tools possible. You may also need to combine roughing and finishing in the same toolpath, as the toolpath may be too thin for separating the two processes.
To be successful with your micro milling machine you will also need to work with high spindle RPMS. This will ensure that you work with reasonable feedrates. The only way that you can increase machine speed is to use the highest rpms tolerable. As you cannot hear the cutter’s health, you will need to get your feeds and speeds correct the first time. If you fail to do so, tools can snap easily. As with everything, practice makes perfect.
Scaling down from a normal CNC milling machine or a CNC turning machine to a micro machine can feel like working with a toy. Remember as a child you had a toy garage or a toy ironing board? Everything was scaled down in your own little world to make you feel big. Well, when it comes to micro milling, everything is scaled down to make parts of the greatest accuracy.
Whether you are swapping over from a traditional machine to a micro machine, or you are adding a desktop machine to your operations, all the above points should be noted. With a micro machine, you will be able to achieve greater levels of accuracy and extremely high quality parts. But, like everything, there is a learning curve involved. You will not be able to feel your machine as it moves, making cuts. You need to fine tune your ear to adapt to your new machine, working with the greatest precision to become a true success.
We live in a world where the word hybrid is now common. Perhaps you have thought about buying a hybrid car? Or maybe you have ridden on a hybrid bus? So it should not come as a shock to learn that hybrid additive manufacturing is now common place in CNC machining UK news. Used successfully for complex moulds, tools that used to be manufactured in the Far East can now be manufactured right at home in UK.
Not only can CAD/CAM and hybrid additive manufacturing makes these tools that before were outsourced; the new techniques ensure that the tools are made in half the conventional time. We all know that speed and quality are of the highest importance when it comes to manufacturing. And you will be pleased to learn that quality is not being compromised by using this ultra fast hybrid technology.
CNC Machining UK News : From the Far East to Back Home
Traditionally the process of manufacturing mould tools for complex parts is long and time-intensive. Between the sign off of a design and the delivery of the tools in the UK there was normally at least a gap of 4 months. Thankfully times have changed and innovation has cut mould making times drastically.
Hybrid additive manufacturing is finding its way into toolmaking, as an exciting new technology. Hybrid machining and metal additive manufacturing allows for moulds to be made more quickly and cost-effectively than ever before. The first installation of this kind in the UK was at OGM. The new tech is creating waves, and transforming the way moulds are made. In turn, the UK is enjoying a change in the manufacture of plastic parts.
One Machine, Two Technologies
The new hybrid technology that includes metal additive manufacturing and machining in one machine is changing the face of mould production. Customers are enjoying much quicker production times for complex moulds, and at a really affordable price. Combining traditional machining with metal additive manufacturing is making this all possible. Never before has direct laser sintering been used directly in conjunction with traditional CNC machines. The results are simply stunning and most definitely very impressive too.
How it Works
CNC machining UK news has been transformed by this new technology. So let’s take a look at how it works. The system can build mould features, layer by layer, from powder, using a laser. Upon completion of each layer, excess material is removed allowing for the generation of the next layer and the geometry of the tool.
This new technology is cutting production times by up to 50%. That’s not forgetting that this technology was not available before in the UK, and long wait times for outsourced products needed to be added to the overall timescale. A solid block is the basis for the technology. Onto this, more complex structures are added with each layer. The type of mould features produced would be extremely difficult to produce using any other type of technology.
Like with anything, preventative maintenance can prevent costly mistakes. When it comes to CNC machining maintenance, it’s no different. How many times have you been too lazy to look after something, knowing that its lifespan will be decreased? Perhaps you ignore the engine management light on your car and don’t take it in for a service and oil change. CNC machines are no different and they need maintaining.
There are plenty of reasons that you may ignore CNC machine maintenance in the same way you ignore the engine light on your car. Being without your car for a day is inconvenient, and having one machine out of order can often put a stop to your entire production line. What’s for sure however that preventative CNC milling and turning machine maintenance is a must. Below are some tips that will ensure your machines work for longer and always provide the very highest caliber parts.
Daily CNC Machining Maintenance
Some quick tasks you should carry out each day include checking the hydraulic pressure and the fluids to make sure that they are at the correct operating levels. At the same time you should check the chuck pressure, and lubrication level. Your cooling system should also be checked, and your chips cleaned out from the chip pan. Any parts that need to be greased should be greased daily. Your machine should be wiped down daily, and the filter should be cleaned at least once every 40 hours.
Periodic CNC machining maintenance should be carried out every 500 hours or 3 months. Checks necessary include checking the chain on the chip conveyor, and greasing where possible. The filters on the coolant tank should also be checked and cleaned.
Every 1000 hours there are some more preventative maintenance measures that need to be carried out. These are generally carried out by a maintenance engineer or your distributor. The coolant tank of your machine will be cleaned for oil, chips, and sludge. The chuck and jaws will be removed from your machine and cleaned thoroughly. The hydraulic oil will be changed and the tank will be cleaned and drained. Whilst empty, the suction and line filters should also be changed. The radiator will be cleaned at this stage and checks will be made to insure the fins are straight.
The lubrication unit should be cleaned and drained as part of your 6 monthly CNC maintenance. If you have a cooling unit, this should also be drained and refilled. The leveling of your machine will be checked, and adjustments made when necessary. Wipers will be inspected for damage and changed where necessary.
Every 2000 hours there is more preventative CNC machine maintenance that needs to be carried out. Once again this will be done by an engineer or by your distributor. The headstock of your machine will be examined and checked for taper. The spindle will be examined to check if there is any radial or end play. The chuck cylinder will also be checked for run out and the tailstock for taper. Parallelism and inclination of the turret will be examined. Your distributor or engineer will also run programmes to check the X, Y, and Z axes.
All this preventative maintenance is necessary to ensure the smooth running of your machinery. Although you may not appreciate the downtime, it is a small price to pay for the increased productivity and longevity your machine will enjoy.
Whether you are a hobbyist machinist or the owner of a company that uses CNC machines, the basics for preventative maintenance remain the same. Although the same importance to produce high quality parts may not exist when you work as a hobbyist, you still want to prolong the life of your machinery and create parts that are of the very highest standards. With preventative maintenance, your hobbyist machine will last you not just years but decades. Follow the basis for the hours of time the machine has been used as opposed to the number of months, and your preventative maintenance for home machines will only be required once every few years.
The history of CNC machines can be traced back to the Industrial Revolution. Since the Industrial Revolution, life has depended on machines for everything. The first machines were those for textile, these being followed closely by machines used for steel manufacture. CNC revolutionized the manufacturing industry, allowing for an infinite number of designs and shapes to be manufactured effortlessly. In this article we are going to trace back the CNC industry to its very start.
The History of CNC Machines : Precursors to NC
Numerical control was the precursor to CNC, but we can also trace the history of CNC machines back to before NC. Very early attempts at automation began with camshafts. These were designed with ridges in place to control machine tool. The camshaft would turn, and the grooves it found would trigger machine control. This method was a big breakthrough at the time, and was great for carrying out repeated tasks. One fine example of this type of camshaft usage is the carving of gun stocks that were used during WW1. This rudimentary process was not however the birth of Numerical Control, as numbers were not used in the process.
Credit for the first numerical control system was given to John T Parson. Whilst working for his father in the 1940s, he began to experiment, building helicopter rotors for the aerospace industry. Together with Frank Stulen, they developed a rudimentary NC method. One machinist would read coordinates along x and y axes to the other machinist, or machinists, who would then make the appropriate cuts. From here they developed their method more, creating punch cards that could be programmed to provide a system that was fully automated.
Computer assisted design together with CNC machining allowed for further important developments to be made in the 1940s and 1950’s. A programming language was developed that generated coordinates, reducing the time needed to feed instructions to a milling machine. The real breakthrough in CNC came about however in 1959, where the team managed to design a totally automatic programme that produced aluminium ashtrays. By the 1970s, CAD was commonly being sued in conjunction with CNC.
It was at around this time that larger advances in the CNC industry were noted. Automation was now becoming widespread, and all types of material including stone, metal, and wood were being used with CNC machines. This meant that labour costs and times were reduced, and products were being manufactured at a fraction of the cost that they could before.
The history of CNC machines is never ending. With every day there are new advances in both CNC milling and turning technology. Notably, with modern machines, we now find up to 7 axes being used frequently. We also find new types of machines on the factory floor that were only dreamed of before. These include laser cutters, 3D printers, and plasma cutters, that together can create almost any shape imaginable to the very highest quality and specifications.