How to Map Fastening Points for a Torque Reaction Arm Workstation

Selecting a torque reaction arm by torque capacity and nominal reach alone does not guarantee that every fastener will be accessible. In a real assembly workstation, fastening-point height, approach angle, socket length, fixture geometry, and the path between points can all change the tool’s actual working position. A point that looks reachable on a top-view drawing may still be blocked by a clamp or require an awkward tool orientation.

Fastening point mapping turns these separate constraints into usable design inputs before an arm is configured. When KURAN evaluates a workstation, the point layout is considered together with torque, tool weight, and available mounting space. This guide will show you how to establish a coordinate reference, record each fastening point, calculate the actual tool positions, define the working envelope, check interference, and prepare a supplier-ready layout for a torque reaction arm workstation.

Why Should Fastening Points Be Mapped Before Configuring a Torque Reaction Arm?

What Does Fastening Point Mapping Mean?

Fastening point mapping is the process of documenting where each fastener is located and how the tightening tool must approach it. A usable map goes beyond bolt count: it links each point ID to coordinates, height or work plane, tightening direction, and surrounding clearance. Its first purpose is to create a shared geometric description of the task—not to choose a model immediately.

Why Are Torque, Tool Weight, and Nominal Reach Not Enough?

Torque capacity indicates whether an arm is rated for the reaction load, while tool weight affects balancing and nominal reach describes movement limits. These figures alone do not show whether the tool can align with every fastener. Atlas Copco lists maximum torque, tool weight, and arm length as separate parameters in its torque arm range, while its AX1 product information distinguishes vertical, horizontal, and angular tightening orientations. This supports treating arm selection as a multi-variable workstation decision.

What Can Go Wrong Without a Fastening Point Map?

Without mapping, an arm may meet its torque rating yet fail in practice: an extreme point may fall outside the usable envelope, a clamp may block the approach path, or the tool may require an impractical orientation. Closely spaced points can also complicate planned position detection. These risks depend on the actual product, fixture, and tool arrangement. Mapping helps expose them before the design is frozen, but it does not replace structural or safety validation.

What Information Should a Usable Fastening Point Map Record?

Record the Geometry of Each Fastening Point

Assign every fastening point a unique ID, such as P01 or P02, and record its X, Y, and Z coordinates relative to a defined datum. You should also identify the work plane, tightening axis, tool approach direction, and required insertion depth.

A coordinate shows where a fastener is located, but it does not fully describe how the tool must reach it. If the values come from a 2D drawing, photograph, or preliminary estimate, clearly label the source and indicate which dimensions still require verification.

Link Each Point to Its Tool and Tightening Process

For each point, record the target torque, tightening program, tool model, socket or bit, extension length, operation sequence, and number of operations per product.

These fields help the designer identify whether different tools or accessories will change the effective working position. Atlas Copco’s ILG teaching instructions require the workpiece geometry, tool geometry, fastening sequence, and controller configuration to be known during position teaching, illustrating why geometric and process information should be connected.

Capture the Workstation Context

The map should identify the associated product variant, fixture, surrounding clearance, nearby structures, restricted areas, and possible mounting locations. At this stage, you are collecting the conditions rather than deciding the final arm structure.

Do not leave an empty field ambiguous. Mark it as “not applicable,” “not yet confirmed,” or “to be measured” so the supplier can distinguish missing information from an actual zero value.

Use a Traceable Fastening Point Worksheet

A practical worksheet can use the following structure:

Source basis: This recommended project template is compiled from the selection parameters shown in Atlas Copco’s torque arm range and the preparation requirements in its ILG teaching documentation. It is not presented as a mandatory industry-standard form.

How Should a Common Datum and Coordinate System Be Established?

Choose a Repeatable Reference Point

Choose a reference that can be reproduced during every production cycle, such as a fixture datum surface, locating pin, fixed stop, or mounting plate. Avoid using a removable cover, movable clamp, or loosely positioned product edge unless its relationship to the fixture is clearly defined.

ISO 5459:2024 establishes terminology and methodology for datums and datum systems in technical product documentation. It can support consistent communication in this process, although it is a general geometrical product specification standard rather than a torque-arm design standard.

Define the Axes, Units, and Drawing Views

Define the origin and positive X, Y, and Z directions before entering point coordinates. State the measurement units and drawing viewpoint, and add an axis symbol to the top, front, and side views. Use the same Point IDs across every view.

If the customer and supplier use different origins, document the relationship between them instead of converting only part of the dataset. A coordinate list without a visible datum and axis direction can be interpreted incorrectly even when the numbers themselves are accurate.

Separate Nominal, Measured, and Estimated Positions

Separate nominal CAD values, verified measurements, and estimated positions. Final measurements should represent the workpiece in its normal production fixture, not a loose component placed on a table.

Atlas Copco’s ILG teaching procedure requires a real workpiece, normal fastening geometry, a correctly positioned part, and fully mapped tool geometry before teaching positions.

Estimated values may support initial scoping if clearly labeled, but do not release the final arm design until critical coordinates and fixture references have been verified. Once the coordinate frame is stable, the next step is to translate each fastener location into the actual tool and arm-connection positions.

Why Is the Fastener Coordinate Different from the Tool’s Actual Working Position?

Build the Complete Tool Dimension Chain

A mapped coordinate normally identifies the center of the fastener or the point where the socket contacts it. However, the reaction arm supports the tool at its holder rather than at the fastener itself. You therefore need to build a dimension chain from the fastener through the socket or bit, extension, output spindle, tool body, and arm holder.

Record the effective length along the tightening axis and any lateral offset between the output spindle and the arm connection. If one component in this chain changes, the arm connection point may also change even though the fastener coordinate remains the same. Atlas Copco’s ILG teaching procedure similarly requires the tool geometry to be fully mapped before fastening positions are taught.

Record the Tool’s Approach Direction and Working Orientation

For each point, record whether the tool approaches vertically downward, horizontally, upward, or at an angle. Include the travel needed to place the socket onto the fastener and withdraw it after tightening.

A point may be inside the nominal reach but still unusable if the tool cannot remain aligned with the fastener axis or if the tool body contacts the product before the socket fully engages. The required orientation depends on the joint, tool, accessory, and fixture, so it should be verified for the actual application.

Locate the Holder and Allow Space for Tool Accessories

Map the tool’s clamping area, arm holder, handle, trigger, cable or air hose, and rear connector. The holder should not obstruct operating controls, and cables or hoses need sufficient movement space throughout the working path. Desoutter’s official torque-arm installation instructions also treat the tool holder, arm attachment, mounting position, and balancing arrangement as separate installation considerations.

A non-standard tool body may require a dedicated tool adapter and mounting interface. Compatibility should be confirmed from the exact tool dimensions and clamping structure, not from the brand name alone. Once the actual connection point is established, you can calculate the arm’s required working envelope.

How Can the Point Map Define the Working Envelope and Mounting Position?

Identify the Extreme Tool Positions

After converting each fastener coordinate into the actual tool-holder position, plot all positions in the same coordinate system. Identify the minimum and maximum X, Y, and Z values, as well as the specific points that create those limits.

Do not calculate the required reach only from the longest distance between two fasteners. Reach starts from the proposed arm pivot, column, rail, or mounting base and ends at the actual arm-to-tool connection. If the mounting location has not yet been fixed, compare several candidate origins against the same point map.

Convert the Point Distribution into a Working Envelope

The working envelope is the volume and movement range that the tool and holder must cover, rather than a single radius value. It should include:

• Movement between all fastening points;
• Tool approach and withdrawal travel;
• Changes between different working heights;
• Rotation required at joints or tool holders;
• The tool’s home or parking position;
• Allowance for confirmed product or fixture variation.

Keep this geometric allowance separate from obstacle clearance, which should be evaluated in the next stage. A nominal arm length does not prove that every point is reachable because joint limits, minimum retraction distance, and movement geometry can reduce the usable range. Atlas Copco’s torque arm range therefore presents arm length alongside torque capacity, tool weight, structure, and mounting configuration.

Use the Envelope to Screen Mounting and Arm Structures

Once the envelope is defined, compare bench-mounted, side-mounted, floor-mounted, overhead, and gantry configurations. Desoutter’s installation instructions recommend positioning the arm attachment near the torque application point and adjusting its height relative to the workpiece, illustrating why mounting geometry affects usability.

A compact and regular point pattern may suit a bench-mounted linear or dual-axis structure. Longer radial movement may require an articulated or telescopic arm, while a wide area or multiple fixtures may justify a floor-mounted, rail-mounted, or gantry configuration.

These are preliminary screening directions, not final model recommendations. Maximum torque, supported tool weight, structural rigidity, and installation safety must still be evaluated. You can review KURAN torque reaction arm options for different workstation layouts after defining the working envelope. The next step is to check whether obstacles restrict any part of that envelope.

How Should Obstacles, Clearance, and Tool Movement Paths Be Marked?

Add Obstacles and No-Go Zones to the Point Map

Overlay the fastening point map with the outlines of the product, clamps, locating units, cylinders, guards, conveyor edges, bins, displays, and neighboring equipment. Record these boundaries in the same coordinate system and distinguish between fixed, movable, and temporary elements.

Mark no-go zones for the entire tool body, holder, and moving arm sections—not only the socket tip. ISO 12100:2010 describes machinery safety through systematic hazard identification and risk assessment. The point map can provide useful design input for that process, but it does not replace a formal machine risk assessment.

Check the Complete Approach, Tightening, and Withdrawal Path

Trace every operation from the previous point through the following stages:

• Move toward the fastening area;
• Align the tool with the fastener;
• Insert the socket or bit;
• Perform the tightening operation;
• Withdraw the tool;
• Move toward the next point.

Evaluate the swept volume of the tool body, holder, and moving arm sections rather than checking only the tool centerline. A fastener may lie inside the calculated working envelope while a clamp prevents axial entry or the tool housing contacts the product before the socket fully engages.

If the path crosses a moving fixture or guard, document the assumed operating state and any required interlock for later engineering review. Do not treat endpoint reachability as proof of collision-free operation.

Preserve Space for the Operator and Utility Connections

Reserve space for the operator’s standing position, hand and handle movement, visibility, and access to the tool controls. Cable and air-hose routing should also be checked throughout the movement path rather than only at the home position.

ISO 6385:2016 recommends integrating human and technical requirements when designing work systems, while OSHA’s ergonomics guidance includes repositioning work surfaces to reduce excessive reaching.

These considerations are especially relevant when the operator manually guides the supported tool or works beside other equipment. Point mapping can reveal potential constraints, but detailed safety and ergonomic validation should be completed by qualified personnel for the actual workstation.

How Should Product Variants and Fixture Positioning Variation Be Included?

Separate Shared and Variant-Specific Fastening Points

Create an identifiable point set for each product variant, even when several products use the same workstation or fixture. Common Point IDs should only be used when the fastener location and tightening task are genuinely equivalent. Model-specific points should have their own identifiers.

Different colors or drawing layers can make the layout easier to review, but the underlying worksheet should still include a product-variant field. Do not combine points from several products into one unlabelled envelope. Doing so can hide differences in tool orientation, tightening programs, accessories, or operation sequence.

Confirm Whether the Datum Changes During Product Changeover

For every product or fixture change, confirm whether the original coordinate origin and axis directions remain valid. A different locating nest, pin arrangement, fixture height, or workpiece orientation can change the relationship between the fastener coordinates and the arm mounting point.

If a workpiece can be loaded in several indexed positions, either map each defined state separately or document the coordinate transformation and the method used to identify the current state. Atlas Copco’s Industrial Location Guidance documentation distinguishes static part positioning from dynamic referencing for translated or rotated parts, demonstrating that part-location changes must be represented in the control model.

Include Verified Position Variation in the Working Range

Nominal coordinates do not describe every repeated production position. Record the confirmed variation caused by fixture repeatability, component seating, locator clearance, or changeover settings. Use that information to calculate the possible position range for each point and then recheck the overall extreme positions.

Do not add an arbitrary distance to every coordinate and call it a safety margin. The allowance should be based on verified production variation and the intended positioning method. During preliminary planning, use the most demanding confirmed product condition and clearly mark any unverified assumptions.

This step expands the point map from a single ideal product into a realistic production model. The next step is to add tightening sequence, program, and accessory changes.

How Should Tightening Sequence, Programs, and Socket Changes Be Added to the Map?

Assign Process Information to Each Point ID

For every Point ID, record its operation step, target torque or tightening-program ID, completion condition, and applicable product variant. If the process allows the operator to complete points in any order, mark it as a free sequence. If the order is controlled, state the exact point that must be completed next.

Atlas Copco’s Industrial Location Guidance supports both free and forced process orders and can associate a tightening parameter set with a specific position. This illustrates how location data can be connected to process logic.

The point map should record the required sequence, not decide the engineering sequence by itself. Any mandatory order should come from the product, joint, or approved assembly-process specification.

Record Socket, Bit, Extension, and Tool Changes

If different points require different sockets, bits, extensions, or tools, add an accessory ID to each fastening task. Also record when the change occurs and what confirms that the correct accessory has been selected.

In a multi-socket workstation, the KURAN KR004 Smart Socket Selector can guide the operator toward the required socket and link the selection signal to the corresponding tightening program.

A socket selector does not measure or regulate the torque applied to the fastener. Torque remains the responsibility of the tightening tool and its controller; the selector helps reduce mismatches between the accessory, program, and fastening task.

Review the Tool Route Through the Complete Sequence

Plot the route from the tool’s home position through every fastening point, accessory-change location, and final parking position. Check whether the sequence creates repeated long movements, excessive arm rotation, cable twisting, or unnecessary extension and retraction.

If the tightening order is mandatory for assembly or quality reasons, do not change it only to shorten tool travel. Instead, consider adjusting the arm mounting position, accessory arrangement, or tool-handling configuration. Movement should be optimized only within the confirmed process requirements.

The map now represents both position and workflow, providing the information needed to evaluate position detection and process control.

How Does Point Mapping Affect XY/XYZ Detection and Process Control?

Decide Whether Mechanical Support Is Enough

A standard mechanical arm may be sufficient when the workstation mainly needs reaction-torque and tool-weight support, the fastening points are few and visually distinct, and the correct location is reliably managed through another approved process.

Position detection becomes more relevant when the workstation contains similar points, mandatory sequences, multiple product variants, different tightening programs, or a requirement to associate results with specific locations. Position control verifies where the tool is; it does not determine whether the applied torque is correct. Torque and angle remain the responsibility of the tightening tool and its controller.

Use the Point Geometry to Choose Between XY and XYZ

XY detection may be considered when all target positions are on one stable plane, the working height and approach direction are controlled, and no two tasks share the same XY location while differing in height.

XYZ detection may be more appropriate when fastening points lie at different heights, overlap when projected onto the XY plane, or require vertical position to distinguish one task from another. Mountz describes an XY position-control system that calculates tool location from arm encoders, while Atlas Copco’s ILG system documentation describes real-time tool-location calculation in three-dimensional space.

The decision should follow the actual point geometry and required level of point discrimination—not an assumption that more detected axes automatically improve every workstation.

Define an Allowed Position Region for Each Point

For each Point ID, define a target coordinate and an allowed region in which the tool may be enabled. Compare the distance between nearby points with:

• Sensor resolution and repeatability;
• Fixture and workpiece variation;
• Tool-center uncertainty;
• Movement during socket engagement;
• The position-control method being used.

Atlas Copco’s position-teaching documentation includes enabling and disabling volumes as part of the position setup.

There is no universal position tolerance suitable for every workstation. If permitted regions overlap, the reference method, fixture, sensor arrangement, mounting position, or control logic may need to be revised.

Connect Point IDs with Programs, Sequences, and Results

With compatible tools and interfaces, a verified Point ID can be used to enable a tightening program, control the operating sequence, and associate a result with the intended location.

For KURAN workstations, the KR002-B01 Field Controller is intended for workstation-level program execution, point management, sequence control, and I/O device integration. Applications requiring more advanced visual guidance, centralized management, and tightening-data traceability can be evaluated with the KR002-H01 Supervisory Controller.

Once these functional requirements are clear, the point map can be organized into a package for supplier evaluation.

How Should Point Data Be Organized and Validated Before Submission?

Assemble a Supplier-Ready Information Package

Combine the point data into one consistent package containing:

• A fastening-point worksheet with coordinates and process information;
• Annotated top, front, and side views;
• CAD files or a 3D model when available;
• Photographs or videos of the workpiece in its actual fixture;
• Tightening-tool model, dimensions, weight, and operating orientation;
• Socket, bit, extension, and adapter information;
• Maximum torque, program, and sequence requirements;
• Product variants and changeover conditions;
• Available mounting areas and restricted zones;
• Existing controller, I/O, and communication information.

Use the same Point IDs, datum, units, and document revision across every file. If a value has not been verified, label it as estimated or pending confirmation instead of presenting it as an exact measurement.

Validate the Map with the Actual Workstation Conditions

Before submission, review the layout using the actual tool, workpiece, and fixture whenever they are available. Check the extreme points, longest tool configuration, every tightening orientation, all confirmed product variants, approach and withdrawal paths, and the tool’s home and accessory-change positions.

Also confirm that the coordinate units, axis directions, drawing orientation, and datum match across the worksheet and drawings. Atlas Copco’s ILG teaching procedure requires a real workpiece, normal production geometry, correct positioning, and mapped tool geometry before position teaching.

For a complex retrofit or a workstation with limited clearance, digital simulation, a physical mock-up, or an on-site review may be appropriate. Passing a drawing-based reach check does not replace structural, collision, ergonomic, or machine-safety validation. General risk-assessment and verification principles can be referenced from ISO 12100:2010.

Let the Supplier Translate the Map into a Configuration

The supplier can combine the point map with torque capacity, tool weight, mounting conditions, and process requirements to evaluate:

• Standard or customized arm construction;
• Mounting location and base structure;
• Required reach and movement pattern;
• Tool holder or adapter;
• XY or XYZ position detection;
• Controller and poka-yoke integration.

KURAN can use these inputs to compare suitable torque-arm structures and control configurations. The final recommendation should still be based on verified project information.

You do not need to complete every field before making initial contact. Clearly identify missing information, then submit the available workstation parameters to KURAN for a preliminary feasibility review and guidance on what should be confirmed next.

From a Fastening Point Map to an Implementable Torque Reaction Arm Workstation

Fastening point mapping is the bridge between a product drawing and an implementable torque reaction arm workstation. Torque and tool weight establish the load and support requirements; point coordinates define the required reach; tool geometry and approach direction determine the actual working positions; fixtures and obstacles limit the usable movement paths; and sequence, program, and accessory information shows whether position and process control may be needed.

A point map does not replace final engineering validation, but it allows many reach, interference, mounting, and control questions to be addressed before the arm is manufactured or installed. Begin with the information you can verify and clearly identify any assumptions or missing measurements.

You do not need to select a model before contacting a supplier. Share the fastening-point layout, tool model, maximum torque, tool weight, workpiece dimensions, mounting space, and position-control requirements. KURAN can then compare standard and customized configurations and identify which details still require confirmation. You can request a KURAN workstation review using the information currently available.

Frequently Asked Questions About Fastening Point Mapping

Can I Map Fastening Points Without a CAD Model?

Yes, annotated photographs and measured dimensions can support a preliminary review when CAD data is unavailable. Provide top, front, and side views, a visible scale or reference dimension, Point IDs, the intended datum, and key fixture and mounting dimensions. Because photographs can introduce perspective distortion, critical geometry should be confirmed through direct measurement, a dimensioned drawing, or an on-site survey before the arm is manufactured.

How Accurate Do Fastening Point Coordinates Need to Be?

There is no single coordinate tolerance suitable for every workstation. Approximate coordinates may be sufficient to estimate the working envelope during initial evaluation if they are clearly labeled. Final accuracy should consider the distance between nearby points, fixture repeatability, sensor performance, tool-center uncertainty, and the required position-detection method. ISO 5459:2024 supports consistent datum definition, while actual system accuracy should come from the selected sensor and controller specifications.

How Should Recessed or Partially Obstructed Fasteners Be Recorded?

Record both the fastener position and the complete access corridor required by the tool. Include recess depth, opening dimensions, approach angle, socket or extension length, and nearby walls or components. A fastener center may lie inside the arm’s working envelope while the tool body remains unable to enter. A sectional or side-view drawing is generally more useful than a top view alone for this condition.

Can One Torque Reaction Arm Cover Two Adjacent Fixtures?

It may be possible if both fixtures fall inside the arm’s usable envelope and the transition path remains clear. Evaluate each fixture’s datum, fastening orientations, torque requirements, point spacing, mounting support, and the route between work areas. Widely separated fixtures may require a floor-mounted, rail-mounted, or gantry arrangement instead of extending a standard arm beyond its practical range. Compare relevant KURAN torque reaction arm configurations only after mapping the combined area.

Do I Need to Remap the Points After Changing the Tool or Socket?

Recalculate or revalidate the map when a change affects the tool’s effective geometry. This includes spindle length, socket or extension length, clamping location, tool diameter, cable outlet, or approach direction. If a replacement preserves the same dimensions and mounting interface, complete remapping may not be necessary, but extreme positions and clearances should still be checked. Atlas Copco’s ILG teaching procedure also requires tool geometry to be mapped.

How Should Points Be Represented When the Workpiece Rotates or Indexes?

Map each defined workpiece state separately or establish a documented coordinate transformation between states. The control process must also identify the current fixture or index position before selecting the associated tightening task. Atlas Copco’s Industrial Location Guidance distinguishes static positioning from dynamic referencing for translated or rotated parts. If the workpiece position cannot be identified repeatably, the position-control logic may not reliably associate the tool with the intended fastener.

Can KURAN Review a Workstation Before Every Fastening Point Is Finalized?

Yes, KURAN can perform a preliminary feasibility review using the information currently available. Useful inputs include the torque range, tool model and weight, workpiece dimensions, fixture photographs, tentative point layout, mounting space, and expected position-control functions. Clearly identify any estimated or missing data. Final arm dimensions, mounting construction, detection tolerances, and quotation may still depend on verified project information. You can submit the available workstation details to KURAN to begin the review.