Hold It Better, Cut It Better: Using Cover Gasket for Small-Part CNC Vacuum Workholding
Holding small parts securely on a CNC router can be one of the more frustrating parts of production. As parts get smaller, there is less surface area available for vacuum, making it easier for parts—or the surrounding waste material—to shift during machining.
That is where a dedicated vacuum fixture using All Star CNC Products Cover Gasket can make a significant difference.
The fixture shown here demonstrates three important principles of effective CNC vacuum workholding: sealing each part, applying vacuum directly to the part, and controlling the surrounding waste material.
1. Create a Seal Around Each Part
The black Cover Gasket creates a sealed perimeter around each individual part pocket.
That seal helps concentrate vacuum where it is needed instead of allowing air to leak freely across the fixture. When vacuum is directed to a defined area underneath the workpiece, the fixture can generate a more reliable hold on smaller components.
For shops producing the same part repeatedly, this type of dedicated fixture can turn a difficult small-part application into a much more predictable process.
2. Pull Each Part Down With Vacuum
Inside each gasketed area is a vacuum opening that allows vacuum to act directly on the part blank.
Once the material is placed over the fixture and vacuum is applied, the workpiece is pulled firmly against the fixture surface.
A more stable part can mean:
- Less opportunity for parts to move during machining
- More consistent cutting
- Cleaner finished edges
- Fewer interruptions caused by shifting material
- A more repeatable production process
For repetitive CNC jobs, consistency is often just as important as raw cutting speed.
3. Don’t Forget About the Waste Material
One feature that is easy to overlook in a dedicated vacuum fixture is the surrounding waste material.
The additional vacuum ports visible in the black fixture material are positioned to help hold the waste portion of the sheet in place as well.
That matters because the finished part is not the only material experiencing cutting forces. If the surrounding skeleton or waste material moves, it can interfere with the cutting process or neighboring parts.
The goal is simple:
Hold the parts and hold the waste.
A properly designed fixture controls both.
Why Dedicated CNC Vacuum Fixtures Matter
A dedicated fixture can be especially valuable when a shop repeatedly machines the same parts.
Instead of relying entirely on a conventional spoilboard for every job, the operator can create a fixture specifically designed around the geometry of the components being produced.
Cover Gasket allows the vacuum zones to follow the shape of the parts being held. This makes it possible to create targeted vacuum zones for round parts, irregular parts, narrow parts, or other components that may be difficult to hold using conventional methods.
Once the fixture is built, it can also be reused for future production runs.
Small Parts Require a Different Workholding Strategy
Large sheets typically provide plenty of surface area for vacuum. Small parts are different.
As the available surface area decreases, good vacuum management becomes increasingly important. Rather than simply trying to increase vacuum, shops can often improve holding performance by controlling where the vacuum is applied and where air is allowed to enter.
A dedicated fixture with Cover Gasket helps create that controlled environment.
Instead of treating the entire CNC table as one large vacuum area, the fixture concentrates vacuum around the parts that actually need to be held.
The Bottom Line
Better CNC machining starts with better workholding.
A well-designed dedicated fixture using Cover Gasket can help a shop:
Seal the part. Hold the part. Hold the waste. Repeat the job.
For manufacturers machining small or repetitive components, improving the fixture may be one of the simplest ways to improve the entire cutting process.
Need Help With a CNC Vacuum Workholding Application?
Every CNC application is different. Part size, material, vacuum pump capacity, fixture design, cutting strategy, and available surface area can all affect workholding performance.
All Star CNC Products works with CNC users to help identify practical gasket and vacuum-fixturing solutions for their applications.
If you’re struggling to hold small parts, repetitive parts, or difficult shapes on your CNC router, send us a photo of your setup and the parts you’re trying to machine.
We may be able to help you find a better way to hold them.
