Vacuum Workholding in Aerospace & Defense Manufacturing

There are many variables in aerospace machining, but one of the least appreciated is how the part is held.

Thin walls, large flat panels, and delicate geometries expose the limitations of traditional clamping methods.

 

Why Traditional Workholding Falls Short

Mechanical clamping applies force focused in small areas, often distorting the part during machining. This leads to several challenges.

• Sidewall deflection
• Part distortion
• Inconsistent flatness
• Operator-induced variables in setups
• Customized fixtures for every part

 

A Different Approach: Vacuum Workholding

Vacuum workholding removes localized pressure and replaces it with uniform force across the entire surface of the part.

No clamps. No side pressure. No induced distortion. However, not all vacuum workholding is created equal. DATRON has mastered vacuum workholding with decades of experience and solutions that keep pace with modern manufacturing.

How Vacuum Workholding Works

Vacuum holding force works on the principle of pressure differential.

• Force = Pressure × Area
• Up to ~14.7 PSI at sea level
• Typical real-world: 10–13 PSI effective when accounting for vacuum inefficiency and losses

 

Elevation Impact

Atmospheric pressure decreases with increasing elevation, reducing the maximum holding force.

• Sea level: ~14.7 PSI (New Orleans, LA)
• 5,000 ft: ~12.2 PSI (Denver, CO)
• 10,000 ft: ~10.1 PSI (Leadville, CO)

Why Vacuum Matters for Your Parts

Vacuum workholding opens a new world of possibilities, enabling stable machining of sensitive features.

Thin Walls Without Distortion

• No lateral clamping pressure
• Improved dimensional accuracy
• Better surface finish

Parts Stay Flatter

• Uniform holding force
• No lifting or bowing
• Consistent flatness

Reduced Setup Time

• Lay down a piece of DATRON VacuCard
• Place the part on the table and turn on the vacuum
• No more complex fixtures
• Faster changeovers

Better Repeatability

• Consistent holding conditions
• Reduced operator variability
• Reliable production output

Ideal for High-Speed Machining

Vacuum workholding is well-suited for high-speed machining. Lower cutting forces, combined with vacuum stability, yield optimal results and unlock entirely new possibilities.

DATRON Vacuum Workholding Advantages

How do DATRON’s vacuum solutions stand apart from the competition? Our system is uniquely designed to eliminate the pain points of traditional gasketed vacuum fixturing.

• Sacrificial layer of DATRON VacuCard
• Allows you to mill through your part without reconfiguring gaskets for each part
• The VacuCard acts as an infinitely configurable gasket that never needs to be adjusted for your part
• Integrated system design with integration in the DATRON next control
• Control vacuum output and zoning directly on the control and within your programs
• Pause your program if the vacuum forces drop below your set threshold
• Start the process with the push of a button
• Zoned vacuum control
• Up to 6 programmable zones and 150 manually adjustable zones
• MQL coolant allows perfect finishes and is fully compatible with DATRON vacuum systems
• Available adhesive assist with VacuCard +++ allowing users to hold even the smallest parts

How to Size Your Vacuum Pump

Are you curious about how to size your vacuum pump for our vacuum tables? The good news is the work is already done for you. DATRON not only provides you with vacuum plates themselves, but also the correct vacuum pump for your application. Our sales and engineering team has the experience and training to review your specific application and recommend the best solution to solve your manufacturing constraints. We prefer to review each application to ensure we provide the best solution to your manufacturing pain points.

What is VacuCard?

One thing we hear a lot in the field is VacuCard: “Oh, the paper on top of the vacuum table.” VacuCard is far more than paper; while it is paper-based, it is a specifically engineered sacrificial layer that provides an air-permeable cutting surface and is specifically coated to ensure it maintains vacuum flow under the harshest conditions inside the machining area. The VacuCard not only provides backing for your part but also maintains a consistent holding force and is compatible with our MQL systems, ensuring you can adequately cool your parts and tools during machining operations.

VacuCard is offered in two versions: standard and adhesive grid. The addition of the adhesive grid provides a production-ready method for holding even the smallest parts. Personally, I’ve had success holding parts under .5” in diameter with multiple holes drilled through the part.

Using DATRON Vacuum Systems on Non-DATRON Equipment

We get asked quite often, can you use DATRON’s vacuum systems on non-DATRON equipment? The short answer is maybe. The longer answer is that DATRON vacuum systems were designed from the ground up to work seamlessly with our entire lineup of machining centers. Many of the features that make them work so well on our machining centers are missing from other machines. Through table vacuum ports enable quick setup, seamless integration, and eliminate the need to run vacuum hoses. Our high-speed spindles create less cutting force and are perfectly designed to pair well with our vacuum systems. Coolant is another factor to consider; our systems are not compatible with flood coolant.

Another question we get often is can I use DATRON VacuCard on non-DATRON vacuum tables? Many have tried, and the general consensus is it’s not a good fit. Typical vacuum tables use venturi vacuum generators, which don’t provide sufficient vacuum volume for effective operation with VacuCard. Also, gasketed vacuum fixtures don’t support the VacuCard as well as our meandering groove system does.

How to Maximize Vacuum Workholding

Order of operations

• Rethink your programming methods to leave as much surface under vacuum until the final cut out
• Always have a flat side on the vacuum; this may mean switching the order of your operations to ensure you have enough flat surface area to maintain vacuum.
• You may debur and chamfer the backside of your part before drilling your holes from the top.

Leverage tabs

• Don’t be afraid to use tabs to allow more aggressive tool paths
• Then remove your tabs at the end with a small endmill to create a finished part off the machine

Optimize toolpaths for Vacuum

• Use toolpaths that ensure stress is relieved consistently across the material
• Reduce sidewall loads when nearing the final cutout of your parts

Ensure your material is flat

• Use precision-ground stock or face your stock flat before utilizing it for vacuum work holding
• If the surface isn’t touching the VacuCard, you will not have vacuum holding

Final Thought

In aerospace and defense manufacturing, how the part is held often determines success and is one of the most overlooked parts of the process.

Vacuum workholding removes variability and enables consistent, high-quality production. Our customers have come to the same conclusion DATRON has. There is simply no better way to fixture your flat parts than our vacuum systems.

The entire DATRON lineup is designed to work effortlessly with our vacuum systems. Every detail is carefully thought out and engineered as a single system to quickly enable part production.

Simplify how you hold complex aerospace parts. Explore DATRON vacuum workholding solutions today.