Introduction
In the age of precision manufacturing, time is everything. Whether it’s woodworking, aerospace or precision metalworking, the demands of production have changed, and so have the ways manufacturers hold workpieces in place while machining them. With so many clamping systems available today, vacuum chucking/suction tables have quickly become a preferred choice for the manufacturer who demands speed along with the ability to be extremely precise.
Why? For in the mass production business, any time saved and every millimeter of precision are felt directly on the bottom line. A vacuum clamp system provides rapid and reliable clamping, free from mechanical clamping devices and deeper than conventional clamps. It’s fast, repeatable and most importantly, designed for the speed of modern industry.
In this blog, we’ll go into the nuts and bolts of how vacuum clamping technology functions, as well as advantages and practical reasons why manufacturers are incorporating it as part of their CNC set-up in factories across the globe!
What Is Vacuum Clamping?
But, you may be asking yourself: What is this technology and what are the benefits? Vacuum clamping is a steadying process in which the pressure of the atmosphere holds the piece in place. It secures the workpiece by applying vacuum pressure to it, and attaches to your current set up with suction force rather than mechanical jaws or bolts.
The concept is simple, but brilliant: Virtually all unwanted movement during machining, milling, engraving or drilling work is due to the fact that air flowing beneath a workpiece cause vibration. CNC machining in particular has fully embraced this practice since the process is a standardized one where perfect, identical result can be achieved every time.
With a well-chosen vacuum clamping system CNC production will be able to work with high batches of materials easily and the setup time, level of stability is perfect.
How Does a Vacuum Clamping System Function?
To help understand why it works so well, knowing how vacuum clamping works can provide some insight. The vacuum workholding device works with atmospheric pressure and vacuum (around 1 bar or 14.7 psi at sea level).
Here’s what it usually looks like, one step at a time:
● The vacuum pump evacuates the air underneath the workpiece providing an air pressure difference.
● Atmospheric pressure forces the workpiece uniformly down onto the fixture to provide a high clamping force.
● The vacuum is released after machining, for instant removal and replacement of the part.
● The workpiece is held down on a flat vacuum plate or fixture with rubber gaskets.
In other words, it’s neat and tidy, doesn’t take up much space or require physical clamping tools that might obstruct cutting paths or surface finishes.
Benefits of Vacuum Clamping in the Contemporary Fabrication Industry
1. Faster Setup and Reduced Downtime: Conventional clamping means often must be adjusted by hand and tightened, and aligned between operations using up precious minutes. Setup time is drastically minimized with vacuum clamping. Operators just insert the material, turn on the vacuum and do the machining, perfect for high-volume, repetitive jobs. The result? Faster cycle times and more machine time overall.
2. Even Clamping Pressure: Clamp marks are one of the most common defects that can occur with a mechanical clamp, especially on thin or fragile work. Vacuum clamping technology, on the other hand, applies uniform pressure to the entire surface, minimizing distortion and ensuring dimensional accuracy. It also promotes uniform pressure distribution, which helps improve surface finish quality and minimizes vibration during machining, an important consideration when working to tight tolerances.
3. Unrestricted Tool Access: One of the issues we wanted to address with traditional clamping systems was eliminating obstructions caused by clamps and bolts. They may be constraining the tool movement and need additional programs to prevent the collision.
In vacuum clamping from below, the top of the workpiece remains free. This requires cutting tools to have unlimited access, better contour capabilities and thus improved part geometries in CNC milling.
4. For Thin or Weak Materials: Over-clamping of thin sheet metals, composites and plastics can cause warping, cracking, and irregular surfaces. Vacuum systems exert an even, mild pressure which are great for these materials.
Which is why sectors such as aerospace, electronics, and woodworking depend on vacuum clamping systems to manipulate lightweight materials without causing any harm.
5. Quick Changeovers for High-Volume Production: Time it takes to change fixtures between batches is a major factor in large-scale production. A vacuum clamping system cnc machine allow for quick changeovers–just release the vacuum to unload finished parts and load new ones.
It is precisely this performance profile which has turned vacuum clamping technology into a staple of lean production environments, where cutting idle times down to the absolute minimum is crucial.
6. Enhanced Safety and Cleaner Workspaces: Unlike mechanical clamps such as those that may rattle loose or shear off under load, vacuum systems maintain constant holding force so long as pressure is present.
In addition, most personal systems feature vacuum sensing to sense loss of vacuum and stop machining if this occurs thereby preventing accidents. What is more, by eliminating the rat’s nest of mechanical clamps that are typically needed to fixture a part, it provides easier-to-maintain and safer workstations.
Common Applications of Vacuum Clamping
Vacuum system flexibility allows to use this equipment for a great variety of industries and applications such as:
● Woodwork: Can be used to cut and shape large wooden boards or MDF of a very high quality without scratching its surface.
● Composite Manufacturing: Ideal for the aerospace and automotive industries to precisely trim composite panels.
● Glass and Plastic Processing: Sparing brittle material which cannot bear traditional clamping pressure.
● Engraving and Sign Making: Will hold secure during fine detail work or while laser cutting.
● NC Milling and Engraving: Die caster is suitable for clamping of flat panels, golden plates, aluminum sheets and other products safety used to the milling or engraving.
In short, if you have to machine flat and/or sensitive material quickly and accurately, then vacuum clamping is indispensable.
Why Are Manufacturers Moving to Rotary Vane Compressors?
With manufacturing moving faster and becoming more data-driven than ever before, vacuum clamping systems are enabling factories to cut inefficiencies and eliminate bottlenecks.
Mechanical clamps Mechanical (traditional) clamps are a labor intensive and repetitive process. Vacuum systems, on the other hand, readily integrate with automated manufacturing lines and work well with robotic handling and CNC programming. High-mix, low-volume industries (aerospace, for example) like vacuum clamping for its adaptability, high-volume industries (furniture and packaging) prize it for speed and repeatability.
The increasing move to vacuum clamping is also influenced by a green aspect. As air is a clamping medium vs. lubricants or coolants, the use of Taper shrink enhances cleanliness and delivers greener manufacturing.
Vacuum Chucks for Securing the Workpiece during Machining in CNC Machines. Perhaps the most popular and efficient purpose vacuum systems are used for is in CNC machining. A vacuum clamping system CNC set up can be utilized to machine with precision without the mechanical interference you may be accustomed to.
Vacuum tables in CNC setups can be separated into sections so different areas are able to be powered on and off independently, handy if you’re milling a few small items at once, all on the same sheet. This means the holding power is constant, regardless of what shape or size you are cutting.
For instance, with a CNC router cutting aluminum or acrylic sheets, vacuum fixtures can clamp parts so firmly that an operator can cut multiple layers at once without any slipping. It is this type of flexibility that provides vacuum with a distinct advantage for manufacturers concentrating on both throughput and accuracy.
Challenges and Considerations
As obvious as the benefits are, however, vacuum clamping systems do have their shortcomings. Manufacturers must consider:
● Flat contact: To be held effectively, the surface that the workpiece can reach should have enough area for adsorption.
● Vacuum Pump Maintenance: It is important to maintain your vacuum pumps for the appliance to obtain proper pressure and avoid leaks.
● Holding Force and Limits: Mechanical clamping backup may still be needed for very heavy or high-force machining.
● Product Porosity: A porous product such as MDF can negatively affect vacuum hold down. May need an additional gasket or sealer if there is a gap.
All the same, with good system design there’s not much harm that can’t be addressed.
The Next Generation of Vacuum Clamping only from Festool
Vacuum clamping technology is developing and adapting to the new automated and smart systems that are becoming more prevalent within the sector. Today, they offer digital sensors and Internet of Things-enabled features to provide continuous diagnostics of vacuum pressure, part position and cycle counts.
Hybrid systems are also starting to appear, marrying vacuum clamping with mechanical locks, the best of both worlds: speed and strength. As sustainability holds the world’s attention, many manufacturers are also choosing energy-saving vacuum pumps that require less power but perform on an ongoing basis.
In other words, vacuum clamping systems will be the indispensable partners for all types of high-precision, high-volume, and eco-friendly production lines in the year 2019.
Conclusion
The new factory runs on speed, precision and versatility, and all three are products of vacuum clamping. Switching from traditional fixtures to efficient vacuum systems allows for fast set up, higher precision and an optimized flow of the complete production.
Whether you use our solutions on a CNC machine, woodworking or in the production of composite material parts: vacuum clamping technology will not only speed up your work processes but also improve the quality and precision.
As with all technology, vacuum clamping technology will continue to advance into even smarter controls, predictive monitoring systems and hybrid automation.
Therefore, if your business is interested in taking production speed and quality to the next level without boosting costs, it’s likely that vacuum clamping system CNC machine setup is exactly what you need.
