Incorrect Profile Dimensions After Delivery — Tooling Fault or Setup Error?

One of the most serious production quality disputes in roll forming machines occurs when the finished profile dimensions do not match the approved drawing

One of the most serious production quality disputes in roll forming machines occurs when the finished profile dimensions do not match the approved drawing after delivery and installation.

Customers may report:

• Profile width incorrect

• Rib height out of tolerance

• Leg lengths inaccurate

• Lip angle incorrect

• Bend radii inconsistent

• Overall cover width mismatch

• Hole position offset (if punched profile)

When this happens on a new machine under warranty, the core question becomes:

Is this a tooling manufacturing defect — or a setup and calibration issue?

This guide explains how incorrect profile dimensions occur, how to determine responsibility, and how to structure a technically sound warranty claim.

Why Profile Dimension Disputes Are Critical

Incorrect profile dimensions affect:

• Roofing installation compatibility

• Structural load capacity

• Purlin interlocking

• Fastener alignment

• Project approvals

• Compliance with building codes

Unlike cosmetic issues, dimensional errors can invalidate contracts or cause project rejection.

If a machine was sold to produce a specific drawing, dimensional accuracy is not optional.

First Question: Was the Approved Drawing Clearly Defined?

Before assigning responsibility, confirm:

• Was there a signed final profile drawing?

• Were tolerances clearly stated?

• Was a sample approved before shipment?

• Were hole positions included in drawing?

• Was material grade specified?

If documentation is unclear, disputes become harder to resolve.

Clear engineering drawings protect both buyer and manufacturer.

Common Causes of Incorrect Profile Dimensions

1. Incorrect Roll Tool Manufacturing (Manufacturing Fault)

If roll tooling was machined incorrectly:

• Rib height may be too high or too low

• Leg angles may be off

• Lip return may not form correctly

• Cover width may not match

This is a tooling manufacturing defect.

If roll geometry does not match approved drawing, supplier responsibility applies.

2. Improper Forming Progression (Setup Issue)

If machine stands are not adjusted correctly:

• Profile may open or close

• Width may vary

• Bend angles inconsistent

Sometimes profile is correct once properly balanced.

Improper setup is usually operator-related — unless commissioning was performed by supplier.

3. Material Thickness or Tensile Variation

Higher tensile steel may:

• Spring back more

• Reduce final bend angle

• Change rib height

If material grade differs from original design assumption, dimensional shift may occur.

Responsibility depends on whether machine was rated for that material.

4. Shaft Runout or Stand Misalignment

If shafts are not aligned:

• Roll pressure fluctuates

• Forming is uneven

• Dimensions vary across width

If measurable alignment error exists in new machine, warranty responsibility may apply.

5. Frame Flex Under Load

Structural flex may:

• Shift stand alignment

• Change bend angles

• Cause width drift

If frame rigidity is insufficient for rated gauge, this is a design issue.

6. Incorrect Punch-to-Form Synchronisation

In machines with punching:

• Hole position may not align with formed rib

• Dimensional tolerance may shift

If encoder calibration was incorrect during commissioning, supplier responsibility may apply.

Width Errors vs Height Errors — Diagnosis Differences

Understanding which dimension is wrong helps identify root cause.

Cover Width Too Narrow

Possible causes:

• Over-forming early stands

• Excessive pressure

• Tool geometry mismatch

Often setup-related — unless tooling incorrect.

Cover Width Too Wide

Possible causes:

• Under-forming

• Material springback

• Insufficient forming pressure

May be setup or material-related.

Rib Height Inconsistent

Possible causes:

• Roll machining error

• Stand misalignment

• Shaft runout

Persistent rib height error often indicates tooling issue.

Lip Angle Incorrect

Possible causes:

• Tooling angle error

• Material tensile difference

• Inadequate final forming pressure

If lip angle never reaches design even under correct setup, tooling may be incorrect.

Tolerance Matters — What Is Acceptable?

Typical roll forming tolerances:

• Width: ±1.0–2.0 mm

• Rib height: ±0.5–1.0 mm

• Bend angle: ±1–2 degrees

If deviation exceeds reasonable industrial tolerance, further investigation is required.

If no tolerance was defined in contract, disputes become more complex.

When Incorrect Dimensions Are a Setup Issue

Most dimensional disputes are setup-related when:

• Machine recently adjusted

• Operator changed stand pressure

• Material thickness changed

• Machine not fully calibrated after installation

Fine adjustments often resolve minor dimensional variance.

When Incorrect Dimensions Are a Warranty Issue

Warranty responsibility may apply if:

• Tool geometry does not match approved drawing

• Tool machining error confirmed

• Machine cannot reach approved dimensions under any adjustment

• Frame flex prevents stable forming

• Shaft alignment causes inconsistent pressure

If machine physically cannot produce approved profile under rated material, this is a manufacturing defect.

Structured Diagnosis Process

To avoid blame-based disputes, follow this process:

Step 1: Measure Finished Profile Accurately

Use calibrated tools to measure:

• Cover width

• Rib height

• Lip angle

• Overall depth

• Hole position (if applicable)

Document multiple samples.

Step 2: Compare to Approved Drawing

Confirm whether deviation exceeds agreed tolerance.

Step 3: Verify Material Specification

Confirm:

• Thickness

• Tensile strength

• Coating type

Material variation may explain minor changes.

Step 4: Adjust Forming Progression

Reduce or increase pressure gradually to determine if profile can reach spec.

If machine cannot physically achieve correct dimensions, tooling or design may be wrong.

Step 5: Inspect Tooling Geometry

Check:

• Roll machining accuracy

• Tool wear (if applicable)

• Stand squareness

If tooling dimension differs from approved drawing, manufacturer responsibility applies.

Real Case Example

A 1000 mm cover roofing machine delivered with consistent 6 mm width shortage.

Supplier claimed setup issue.

Inspection revealed:

• Roll tooling width machined 3 mm short per side

• Progressive forming exaggerated width loss

• No possible adjustment could achieve 1000 mm cover

Supplier remanufactured roll tooling under warranty.

Root cause: tooling machining error.

Preventing Profile Dimension Disputes Before Purchase

Before buying a roll forming machine:

1. Sign off final approved drawing

2. Confirm dimensional tolerances in writing

3. Request sample production video

4. Confirm material grade used in design

5. Request roll tool machining documentation

6. Confirm commissioning procedure

Clear documentation prevents post-delivery disputes.

Signs a Dimensional Problem Is Structural

Look for:

• Increasing error at higher speeds

• Profile changing under heavier gauge

• Consistent misalignment on one side

• Stand movement during operation

These may indicate frame or alignment problems — not setup error.

Frequently Asked Questions

Are profile dimension errors usually setup-related?

Often yes — but persistent dimensional errors may indicate tooling defects.

Can material tensile strength affect dimensions?

Yes. Higher tensile steel increases springback.

Should a new machine produce exact drawing dimensions?

Within agreed industrial tolerance, yes.

Can shaft runout affect profile dimensions?

Yes. Uneven pressure leads to dimensional variation.

What if machine cannot reach correct dimension at all?

This likely indicates tooling manufacturing error.

Are tolerance limits legally important?

Yes. Without defined tolerances, disputes become subjective.

Final Conclusion

Incorrect profile dimensions after delivery are not automatically a warranty defect — but they are not automatically setup error either.

Responsibility depends on:

• Approved drawing clarity

• Defined tolerances

• Tooling geometry

• Shaft alignment

• Frame rigidity

• Material specification

• Commissioning accuracy

If the machine cannot physically achieve approved dimensions under correct setup and material, it is a manufacturing fault.

Without structured measurement and documentation, disputes become opinion-based.

With proper engineering analysis, liability becomes clear.