How to Machine More Sides in One CNC Setup |
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Learn how workholding selection, tool access and operation planning can help complete more machining before a part must be repositioned.
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Machine Capability and Workholding Access
Machining more sides of a component in one setup depends on two separate factors: what the machine can reach and what the workholding leaves exposed.
A multi-axis machine may be capable of approaching a workpiece from several directions, but clamps, vise jaws or fixture components can still obstruct the cutting tool. On a three-axis machine, the top surface and accessible perimeter features may be machined without moving the workpiece, but the machine cannot reach the underside without another setup or specialized arrangement.
Good workholding does not add axes to a machine. It helps the machine use more of the access it already has.
The practical goal is to expose as many required surfaces as possible while keeping the component securely located, supported and clamped throughout the operation.
A multi-axis machine may be capable of approaching a workpiece from several directions, but clamps, vise jaws or fixture components can still obstruct the cutting tool. On a three-axis machine, the top surface and accessible perimeter features may be machined without moving the workpiece, but the machine cannot reach the underside without another setup or specialized arrangement.
Good workholding does not add axes to a machine. It helps the machine use more of the access it already has.
The practical goal is to expose as many required surfaces as possible while keeping the component securely located, supported and clamped throughout the operation.
Why Machining Access Matters
Every time a part is removed and repositioned, additional work may be required:
Completing more operations from one location can reduce handling, setup time and opportunities for alignment error. However, eliminating a setup is valuable only when the remaining workholding arrangement is secure and provides the accuracy the part requires.
- Stopping the machining process
- Cleaning the workpiece and workholding
- Establishing a new orientation
- Locating and clamping the part again
- Re-establishing work offsets
- Indicating critical surfaces
- Verifying alignment and dimensions
- Proving the next operation
Completing more operations from one location can reduce handling, setup time and opportunities for alignment error. However, eliminating a setup is valuable only when the remaining workholding arrangement is secure and provides the accuracy the part requires.
What Does “More Sides in One Setup” Mean?
The phrase can describe several different machining situations.
Top and perimeter machining
A part is supported from below and clamped at low points around its edges, leaving the top and portions of its perimeter accessible.
Multiple faces on a multi-axis machine
A fourth or fifth machine axis rotates or positions the workpiece so the cutting tool can approach different faces without manual repositioning.
Open-face machining
Workholding is positioned away from the upper machining surface, allowing unobstructed access for face milling, drilling, pocketing and other operations.
Completing more features before re-fixturing
Even when every side cannot be reached, an improved setup may allow substantially more features to be completed before the part is moved.
The correct objective is not always “five sides in one setup.” For some parts, reducing three setups to two may provide a significant improvement.
Top and perimeter machining
A part is supported from below and clamped at low points around its edges, leaving the top and portions of its perimeter accessible.
Multiple faces on a multi-axis machine
A fourth or fifth machine axis rotates or positions the workpiece so the cutting tool can approach different faces without manual repositioning.
Open-face machining
Workholding is positioned away from the upper machining surface, allowing unobstructed access for face milling, drilling, pocketing and other operations.
Completing more features before re-fixturing
Even when every side cannot be reached, an improved setup may allow substantially more features to be completed before the part is moved.
The correct objective is not always “five sides in one setup.” For some parts, reducing three setups to two may provide a significant improvement.
Plan Around the Complete Machining Sequence
Workholding should be selected after reviewing all the operations required—not only the first toolpath.
Before building the setup, identify:
Before building the setup, identify:
- Which surfaces and features must be machined
- The direction from which each feature must be approached
- The surfaces that will establish the primary datums
- Areas available for support and clamping
- Features that will remove potential clamping surfaces
- Expected cutting forces during each operation
- Required spindle, toolholder and fixture clearance
- Whether the part can remain stable as material is removed
- Which surfaces will remain for a final setup
- How the workpiece will be located after repositioning
How Top Clamping Restricts Access
Strap clamps and other top-mounted clamps can provide effective workholding, but they occupy areas above the component.
Depending on their placement, top clamps may obstruct:
Whenever the application permits, low-profile or edge-based clamping can leave more of the top surface and perimeter accessible. The setup must still provide sufficient resistance to sliding, lifting and rotation.
Depending on their placement, top clamps may obstruct:
- Face-milling toolpaths
- Drilled or tapped holes
- Pockets and slots
- Outside profiles
- Edge features
- Toolholder clearance
- Additional surfaces on multi-axis machines
Whenever the application permits, low-profile or edge-based clamping can leave more of the top surface and perimeter accessible. The setup must still provide sufficient resistance to sliding, lifting and rotation.
Workholding Methods for Improved Access
Several workholding methods can help expose additional machining surfaces. Each has applications where it works particularly well.
Machine vises and soft jaws
A machine vise can provide excellent repeatability and rigidity for parts that fit its capacity. Soft jaws can be machined around a specific geometry and may expose much of the workpiece.
Vise bodies and jaws can still restrict access to lower edges or oversized parts. Multiple operations may be required when the component must be flipped or repositioned.
Toe clamps and low-profile clamps
Toe clamps act near the lower edge of the workpiece, leaving more of its upper surface exposed. They can be useful for plates and other parts that provide suitable clamping edges.
Their effectiveness depends on part geometry, clamping direction, supporting surfaces and expected cutting forces.
Fixture plates
Fixture plates provide known mounting locations for clamps, stops, supports and custom components. They can make it easier to create repeatable setups and arrange workholding around required machining areas.
A fixture plate improves flexibility, but tool access still depends on the clamps and locating components installed on it.
Vacuum workholding
Vacuum workholding can provide nearly unrestricted access to the top and perimeter of a suitable flat component. It is often useful for thin sheet or plate materials where mechanical clamps would obstruct the toolpath.
The available holding force depends on surface area, seal quality and material condition. Vacuum systems may not be appropriate for porous, uneven or heavily interrupted parts.
Dedicated fixtures
A dedicated fixture can be designed to provide excellent access, repeatability and loading efficiency for a recurring component. It may be the best choice for stable, higher-volume production.
The design and manufacturing cost may be difficult to justify for prototypes, one-off components and short runs.
Modular workholding
Modular workholding allows clamps, supports and stops to be repositioned for changing part geometries. Low-profile arrangements can provide access to the top and portions of the perimeter while avoiding a custom fixture for every new job.
This can be particularly valuable in high-mix production, where part sizes and required operations change frequently.
Machine vises and soft jaws
A machine vise can provide excellent repeatability and rigidity for parts that fit its capacity. Soft jaws can be machined around a specific geometry and may expose much of the workpiece.
Vise bodies and jaws can still restrict access to lower edges or oversized parts. Multiple operations may be required when the component must be flipped or repositioned.
Toe clamps and low-profile clamps
Toe clamps act near the lower edge of the workpiece, leaving more of its upper surface exposed. They can be useful for plates and other parts that provide suitable clamping edges.
Their effectiveness depends on part geometry, clamping direction, supporting surfaces and expected cutting forces.
Fixture plates
Fixture plates provide known mounting locations for clamps, stops, supports and custom components. They can make it easier to create repeatable setups and arrange workholding around required machining areas.
A fixture plate improves flexibility, but tool access still depends on the clamps and locating components installed on it.
Vacuum workholding
Vacuum workholding can provide nearly unrestricted access to the top and perimeter of a suitable flat component. It is often useful for thin sheet or plate materials where mechanical clamps would obstruct the toolpath.
The available holding force depends on surface area, seal quality and material condition. Vacuum systems may not be appropriate for porous, uneven or heavily interrupted parts.
Dedicated fixtures
A dedicated fixture can be designed to provide excellent access, repeatability and loading efficiency for a recurring component. It may be the best choice for stable, higher-volume production.
The design and manufacturing cost may be difficult to justify for prototypes, one-off components and short runs.
Modular workholding
Modular workholding allows clamps, supports and stops to be repositioned for changing part geometries. Low-profile arrangements can provide access to the top and portions of the perimeter while avoiding a custom fixture for every new job.
This can be particularly valuable in high-mix production, where part sizes and required operations change frequently.
Establish Reliable Support and Datums
Improved access is useful only when the workpiece remains stable and accurately located.
A secure setup should account for:
The clamping arrangement should not rely on friction alone when positive locating features can be used. The appropriate combination of supports, stops and clamps depends on the part and operation.
Large or irregular components may require support across several areas. Thin parts may need distributed support to prevent deflection, while weldments and castings may require adjustable support at uneven surfaces.
A secure setup should account for:
- Downward support
- Horizontal movement
- Part lift
- Rotation
- Deflection
- Vibration
- Changes caused by material removal
The clamping arrangement should not rely on friction alone when positive locating features can be used. The appropriate combination of supports, stops and clamps depends on the part and operation.
Large or irregular components may require support across several areas. Thin parts may need distributed support to prevent deflection, while weldments and castings may require adjustable support at uneven surfaces.
Consider Cutting Forces Throughout the Program
Cutting forces can change as different features are machined. A setup that is stable during light face milling may behave differently during heavy peripheral cutting, drilling or an interrupted cut.
Review:
Review:
- The direction of each major cutting force
- Whether the force pushes the part into or away from its stops
- Whether the workpiece could rotate
- Whether a clamp could lose contact as material is removed
- Whether unsupported areas could vibrate
- Whether heat or stress relief could affect the component
- Whether the final operations remove material near a clamping point
Machining the Outside Profile
Machining an entire outside profile is difficult when the workpiece is clamped from its perimeter or directly against the machine table.
Possible approaches include:
Some parts will still require a second setup to finish clamping areas or machine the underside. The aim is to minimize unnecessary repositioning, not to eliminate a required operation at the expense of stability.
Possible approaches include:
- Raising the part on parallels, pucks or supports
- Clamping below the required profile
- Using sacrificial material beneath the component
- Holding the part through existing holes
- Using custom jaws or a dedicated fixture
- Applying low-profile edge clamping at areas outside the toolpath
- Leaving temporary material for a later operation
Some parts will still require a second setup to finish clamping areas or machine the underside. The aim is to minimize unnecessary repositioning, not to eliminate a required operation at the expense of stability.
Using Multi-Axis Equipment Effectively
Fourth- and fifth-axis machines can provide access to several faces without manual part handling. Workholding must be designed so it does not prevent the rotary axes from delivering that access.
Consider:
A three-axis machine may also complete top and perimeter features in one setup when the workholding provides sufficient access. This is not the same as simultaneous five-axis machining, but it may still reduce the number of manual setups required.
Consider:
- The complete swept area of the workpiece
- Spindle and toolholder clearance
- Fixture height
- Clamp position
- Rotary-axis load limits
- Part balance
- Cable, guarding and enclosure clearance
- Collision risks at every programmed orientation
A three-axis machine may also complete top and perimeter features in one setup when the workholding provides sufficient access. This is not the same as simultaneous five-axis machining, but it may still reduce the number of manual setups required.
When Another Setup Is Still Necessary
Some parts cannot—or should not—be completed in one setup.
Another orientation may be required to:
The objective is to use the fewest setups that can safely and accurately complete the work—not to pursue one-setup machining as an absolute rule.
Another orientation may be required to:
- Machine the underside
- Remove temporary holding features
- Finish areas used for clamping
- Establish a more accurate datum
- Reach features outside the machine’s available axes
- Support the part differently for a heavy operation
- Release material stress before final machining
- Protect a critical finished surface
The objective is to use the fewest setups that can safely and accurately complete the work—not to pursue one-setup machining as an absolute rule.
How Gold Grip Improves Machining Access
Gold Grip Vises is a modular CNC workholding system that positions clamping around the workpiece rather than limiting it to a fixed vise opening.
Its clamping heads apply horizontal and downward force near the lower edge of the component. Depending on the part and configuration, this can preserve access to the top surface and more of the perimeter while reducing part lift.
Repositionable bases, clamping heads and backstops allow machinists to configure the system for different workpieces and machining requirements. Gold Grip can support large components, irregular geometries and multi-part arrangements without requiring a dedicated fixture for every application.
The system may help manufacturers:
Manufacturers can review Gold Grip workholding applications and watch setup and production videos to see different configurations.
Its clamping heads apply horizontal and downward force near the lower edge of the component. Depending on the part and configuration, this can preserve access to the top surface and more of the perimeter while reducing part lift.
Repositionable bases, clamping heads and backstops allow machinists to configure the system for different workpieces and machining requirements. Gold Grip can support large components, irregular geometries and multi-part arrangements without requiring a dedicated fixture for every application.
The system may help manufacturers:
- Complete more operations before repositioning
- Reduce obstructions above the part
- Access additional perimeter features
- Hold components that exceed conventional vise capacity
- Reconfigure workholding for changing parts
- Use more of the available machine table
Manufacturers can review Gold Grip workholding applications and watch setup and production videos to see different configurations.
One-Setup Machining Checklist
Before beginning the operation, confirm:
- Every required surface and feature has been identified.
- The machine can physically approach each planned feature.
- Clamps and supports are clear of all toolpaths.
- Toolholders have sufficient clearance.
- The workpiece is supported against vertical cutting forces.
- Stops or locating features resist horizontal movement.
- The setup prevents part lift and rotation.
- Material removal will not eliminate a required support or clamping point.
- The machine has sufficient travel in every required direction.
- Multi-axis movements have been checked for possible collisions.
- The setup remains secure throughout the complete program.
- A second setup is planned where it is technically necessary.
Frequently Asked Questions
Can a three-axis CNC machine cut five sides in one setup?
A three-axis machine cannot approach a workpiece from the same directions as a true five-axis machine. Depending on the part and workholding, it may machine the top surface and accessible perimeter or side features without repositioning. The underside generally requires another setup.
What is open-face machining?
Open-face machining uses a workholding arrangement that keeps clamps and fixtures away from the primary upper machining surface, providing greater access for face milling, drilling, pocketing and related operations.
How do you machine the full perimeter of a plate?
Possible methods include raising the workpiece above the table, using low-profile clamps, holding through existing holes, using sacrificial material or creating a dedicated fixture. The best approach depends on plate thickness, material, profile depth and cutting forces.
Is it always better to machine a part in one setup?
No. One setup can reduce handling and alignment work, but only when the part can be held safely and accurately. A planned second setup is preferable when it provides better support, access or dimensional control.
How does workholding affect multi-axis machining?
Even when the machine can rotate or tilt the workpiece, vise bodies, clamps and fixture components may block the spindle or toolholder. Workholding must provide clearance at every programmed orientation.
Can modular workholding reduce the number of setups?
It may reduce setups when repositionable components provide access to more surfaces or accommodate different part orientations. The result depends on the part, machine capability and required operations.
What is the difference between fewer setups and faster setups?
Faster setups reduce the time needed for each changeover. Fewer setups reduce how many times the part must be relocated. A good workholding strategy may improve one or both.
A three-axis machine cannot approach a workpiece from the same directions as a true five-axis machine. Depending on the part and workholding, it may machine the top surface and accessible perimeter or side features without repositioning. The underside generally requires another setup.
What is open-face machining?
Open-face machining uses a workholding arrangement that keeps clamps and fixtures away from the primary upper machining surface, providing greater access for face milling, drilling, pocketing and related operations.
How do you machine the full perimeter of a plate?
Possible methods include raising the workpiece above the table, using low-profile clamps, holding through existing holes, using sacrificial material or creating a dedicated fixture. The best approach depends on plate thickness, material, profile depth and cutting forces.
Is it always better to machine a part in one setup?
No. One setup can reduce handling and alignment work, but only when the part can be held safely and accurately. A planned second setup is preferable when it provides better support, access or dimensional control.
How does workholding affect multi-axis machining?
Even when the machine can rotate or tilt the workpiece, vise bodies, clamps and fixture components may block the spindle or toolholder. Workholding must provide clearance at every programmed orientation.
Can modular workholding reduce the number of setups?
It may reduce setups when repositionable components provide access to more surfaces or accommodate different part orientations. The result depends on the part, machine capability and required operations.
What is the difference between fewer setups and faster setups?
Faster setups reduce the time needed for each changeover. Fewer setups reduce how many times the part must be relocated. A good workholding strategy may improve one or both.
Engineered for High-Load Production Environments
Gold Grip Vises torque and clamping force specifications are calibrated and verified under controlled conditions. This reference documentation provides validated torque-to-force data to support safe, consistent, and repeatable clamping.
Intended for engineering reference, process planning, and quality assurance.
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