Dry Film Thickness Measurement for Steel Structures Using Landtek CM-8826FN Malaysia

Dry Film Thickness Measurement for Steel Structures Using Landtek CM-8826FN Malaysia

Introduction

Dry Film Thickness (DFT) measurement is an essential part of protective coating inspection for steel structures in Malaysia.

Steel structures used in factories, warehouses, industrial facilities, infrastructure projects and engineering installations are frequently protected with paint or specialised coating systems.

These coatings help protect steel surfaces against corrosion, moisture and environmental exposure.

However, applying a protective coating is only one part of the process. The final coating thickness must also be checked against the specified requirements.

A coating that is too thin may not provide the intended protective performance, while excessive thickness can create application or curing problems depending on the coating system.

The Landtek CM-8826FN Coating Thickness Meter is a portable digital instrument designed for non-destructive coating thickness measurement on compatible metallic substrates.

For painted carbon steel structures, the instrument uses its Fe magnetic induction measurement function.

This guide explains how to perform dry film thickness measurement on steel structures, including instrument preparation, surface profile considerations, inspection procedures, measurement errors and relevant coating inspection standards.

1. What Is Dry Film Thickness?

Dry Film Thickness (DFT) refers to the thickness of a coating after the coating material has dried or cured.

DFT is commonly measured in:

Micrometres (碌m)

Mils

One mil equals 25.4 碌m.

DFT measurement is widely used in industrial coating inspection because coating specifications frequently establish minimum, nominal or maximum thickness requirements.

Why Is DFT Important?

Corrosion Protection

The specified coating thickness contributes to the performance of a properly selected and applied protective coating system.

Quality Assurance

DFT measurements help inspectors verify coating application consistency.

Project Compliance

Engineering contractors may need documented coating thickness results before project acceptance.

Maintenance Planning

Inspection results can help maintenance teams identify coating thickness variations requiring further investigation.

Coating Application Control

Measurement records can help coating contractors monitor their application processes.

Important: DFT measurement alone does not establish overall coating performance. Surface preparation, adhesion, curing, coating continuity and environmental conditions may also need to be evaluated.

2. What Is the Landtek CM-8826FN?

The Landtek CM-8826FN is a digital coating thickness meter supporting two measurement principles.

Fe - Magnetic Induction

The Fe function is used for measuring suitable non-magnetic coatings on ferromagnetic substrates such as carbon steel and iron.

Typical applications include:

Protective paint on steel structures

Industrial coating on steel beams

Powder coating on steel components

Paint on machinery frames

Suitable coatings on fabricated steel panels

NFe - Eddy Current

The NFe function is used for measuring suitable non-conductive coatings on compatible non-ferrous conductive substrates such as aluminium.

For ordinary painted carbon steel structures, the Fe measurement function is the appropriate choice.

Main Features

Dual Fe and NFe Measurement Capability

External Probe Design

Non-Destructive Coating Thickness Measurement

Portable Digital Instrument

Suitable for Industrial Coating Quality Control

The external probe design allows the operator to position the probe separately from the display unit.

This can be convenient for accessible structural steel components and industrial equipment.

3. Why Steel Structures Require DFT Inspection

Steel structures are commonly exposed to environmental conditions that can contribute to corrosion.

Examples include:

Industrial humidity

Rainwater exposure

Atmospheric contaminants

Coastal environments

Industrial process conditions

Outdoor weathering

Protective coating systems are selected to suit the intended service environment.

DFT inspection helps determine whether the coating thickness meets the specified requirements.

Common Steel Structure Applications

Factory Steel Structures

Steel beams, columns and supporting frames used in manufacturing facilities.

Warehouse Structures

Protective-coated structural steel components used in industrial warehouses.

Industrial Platforms

Steel platforms, walkways and equipment supports.

Engineering Fabrications

Steel frames, brackets and fabricated assemblies.

Industrial Equipment Structures

Steel supports and housings used for machinery installations.

Infrastructure Projects

Suitable protective-coated steel components used in construction and engineering projects.

The inspection method and acceptance criteria depend on the project specification and coating system.

4. Understanding Protective Coating Systems

Industrial steel structures may use multi-layer protective coating systems.

A typical coating system may include:

Primer

Applied to prepared steel to support the intended protective coating system.

Intermediate Coat

Used where the specified coating system requires additional film build or protective properties.

Topcoat

Provides the final exposed coating surface and may contribute to appearance and environmental resistance.

Example of a Multi-Layer Coating System

Coating LayerIllustrative DFTPrimer75 碌mIntermediate Coat125 碌mTopcoat50 碌mTotal Nominal DFT250 碌m

These values are illustrative only and are not a universal specification.

The Landtek CM-8826FN can measure the combined thickness of compatible non-magnetic coating layers above a suitable ferromagnetic substrate.

It cannot independently identify the thickness of each layer after all layers have been applied.

Individual layer thickness may need to be checked during the coating application process.

5. Equipment Required for DFT Measurement

Before performing dry film thickness inspection, prepare the following equipment.

1. Landtek CM-8826FN Coating Thickness Meter

The primary measurement instrument.

2. Appropriate Fe Probe

Used for suitable ferromagnetic steel substrates.

3. Certified or Suitable Reference Standards

Used for instrument verification according to the applicable procedure.

4. Reference Foils

Used for appropriate instrument adjustment or verification.

5. Representative Uncoated Steel Surface

May be required for instrument adjustment, particularly when substrate conditions influence measurement.

6. Inspection Record

Used to document readings, measurement locations and relevant project information.

7. Project Coating Specification

Defines the required coating thickness and acceptance criteria.

For formal inspection, the equipment and documentation must satisfy the applicable quality assurance requirements.

6. Step-by-Step DFT Measurement Procedure

Step 1 - Review the Coating Specification

Before taking measurements, review the project requirements.

Identify:

Coating system

Substrate material

Nominal DFT

Minimum and maximum acceptance limits

Applicable inspection standard

Required sampling frequency

Inspection documentation requirements

Do not assume that all protective coating systems use the same DFT acceptance criteria.

Step 2 - Confirm the Steel Substrate

Verify that the substrate is suitable for the Fe magnetic induction measurement method.

Ordinary carbon steel is typically suitable.

Some stainless steels and specialised alloys may not be suitable for this method.

The substrate must be compatible with the instrument and probe.

Step 3 - Inspect the Coating Surface

Check the measurement area for:

Loose contamination

Surface debris

Visible coating defects

Damaged coating areas

Irregular deposits

Unsuitable probe contact conditions

Remove loose contamination where appropriate without damaging the coating.

Ensure the coating is sufficiently dried or cured for the intended inspection.

Step 4 - Select the Fe Probe

Use the appropriate Fe probe for measurement on suitable steel structures.

The CM-8826FN supports both Fe and NFe functions.

However, ordinary protective-coated carbon steel requires the Fe measurement method.

Step 5 - Verify the Instrument

Check the instrument according to the manufacturer's instructions and applicable inspection procedure.

Use suitable reference standards and reference foils.

Where required, perform adjustment on an appropriate uncoated steel reference surface.

For rough or blast-cleaned steel, additional considerations may apply.

Important: Routine instrument verification or adjustment is not the same as formal traceable calibration.

Step 6 - Position the Probe Correctly

Place the probe correctly against the coated steel surface.

For consistent measurement:

Maintain proper probe alignment.

Avoid excessive tilting.

Ensure stable contact.

Avoid dragging the probe across the coating.

Observe minimum edge-distance requirements.

Consider the effect of curved or irregular surfaces.

Incorrect probe positioning may influence the result.

Step 7 - Take DFT Measurements

Take measurements according to the inspection plan.

For example, a hypothetical inspection may produce the following readings:

Measurement LocationDFT ReadingPoint 1242 碌mPoint 2251 碌mPoint 3247 碌mPoint 4255 碌mPoint 5250 碌mArithmetic Average249 碌m

These values are illustrative and do not represent actual CM-8826FN test results.

The arithmetic average is:

Average DFT = Sum of Readings / Number of Readings

For this example:

1,245 碌m / 5 = 249 碌m

However, a simple arithmetic average does not automatically determine whether the coating passes inspection.

The applicable standard may define specific spot measurements, area measurements, correction procedures and acceptance rules.

Step 8 - Evaluate the Results

Compare the results against the project specification.

For example, a coating system may have a nominal total DFT of 250 碌m.

The inspector must determine whether the results satisfy the actual acceptance criteria.

Depending on the specification, compliance may involve minimum values, maximum values, statistical rules or defined measurement areas.

A reading below the nominal thickness is not automatically a failure unless the applicable acceptance rules establish that conclusion.

Step 9 - Record the Inspection Results

A DFT inspection report may include:

Project identification

Steel component identification

Coating system

Surface preparation information

Instrument model

Probe identification

Calibration status

Verification or adjustment details

Measurement locations

Individual readings

Applicable correction procedures

Acceptance criteria

Inspection date

Inspector identification

Accurate documentation helps maintain traceability and supports project quality assurance.

7. How Surface Roughness Affects DFT Measurement

Surface roughness is an important consideration when measuring protective coatings on steel structures.

Before coating application, steel may be prepared using abrasive blasting.

This process creates a surface profile containing peaks and valleys.

The profile can influence magnetic induction coating thickness readings.

Why Does Surface Profile Matter?

A coating thickness gauge responds to the separation between the probe and the underlying ferromagnetic substrate.

On rough steel, the instrument response can be influenced by the substrate profile.

Therefore, the displayed value may require adjustment or interpretation according to the applicable inspection procedure.

Recommended Approach

Identify the Surface Preparation Method

Determine whether the steel was blast-cleaned or prepared using another method.

Review the Applicable Standard

Confirm whether the inspection specification requires surface profile correction.

Use Appropriate Reference Surfaces

Where required, perform instrument adjustment using representative uncoated steel.

Apply the Specified Correction Procedure

Do not apply an arbitrary correction value.

Record the Method Used

Document relevant adjustment and correction details.

For protective coating projects, ISO 19840 is one recognised reference for DFT measurement on rough steel surfaces.

The applicable edition and project requirements should be checked before inspection.

8. DFT Measurement on Steel Beams and Columns

Steel beams and columns are common structural components in factories and warehouses.

However, different areas of a structural member may have different geometries.

Examples include:

Beam flanges

Beam webs

Column surfaces

Corners

Edges

Welded connections

Measurement Considerations

Flat Accessible Surfaces

These are generally more convenient for probe placement.

Edges and Corners

Measurement results may be influenced by geometry.

Welded Areas

Irregular surfaces may affect probe contact and measurement repeatability.

Curved Components

The probe's curvature limitations must be considered.

Restricted Access Areas

The external probe may offer handling flexibility, but access limitations still depend on the probe dimensions and cable arrangement.

The inspector should follow the required sampling plan rather than selecting only convenient measurement locations.

9. DFT Measurement for Industrial Protective Coatings

Industrial coating contractors may use the Landtek CM-8826FN to support inspection of compatible coating systems.

Typical applications include:

Epoxy Coatings

Suitable epoxy coatings applied over ferromagnetic steel may be measured using the Fe method.

Polyurethane Topcoats

Compatible polyurethane coatings can form part of a multi-layer system measured for total DFT.

Protective Paint Systems

Suitable non-magnetic protective coatings on steel can be inspected.

Powder Coatings

Cured powder coatings on compatible steel substrates may also be measured.

Important Limitation

The instrument measures coating thickness.

It does not directly measure:

Coating adhesion

Surface cleanliness

Soluble salt contamination

Coating cure

Holiday defects

Corrosion resistance

Remaining steel wall thickness

These properties may require separate instruments or inspection procedures.

10. Common DFT Measurement Errors

Error 1 - Incorrect Probe Selection

Using the wrong measurement function can produce invalid readings.

Solution: Use the appropriate Fe probe for compatible steel substrates.

Error 2 - Ignoring Surface Profile

Blast-cleaned steel can influence coating thickness measurements.

Solution: Follow the applicable surface profile adjustment or correction procedure.

Error 3 - Measuring Too Close to Edges

Edge effects can influence the instrument response.

Solution: Follow the manufacturer's probe limitations and inspection requirements.

Error 4 - Poor Instrument Verification

An instrument that has not been properly checked may produce unreliable results.

Solution: Verify the instrument using appropriate reference standards.

Error 5 - Incorrect Probe Positioning

Probe tilting or unstable contact may affect measurement repeatability.

Solution: Maintain proper probe alignment and stable contact.

Error 6 - Insufficient Sampling

A few convenient measurements may not represent the required inspection area.

Solution: Follow the specified sampling procedure.

Error 7 - Misinterpreting Average DFT

An acceptable average does not necessarily mean every inspection requirement has been satisfied.

Solution: Evaluate the results using the relevant standard and acceptance criteria.

11. DFT Measurement Standards for Steel Structures

Several recognised standards and practices may be relevant to protective coating inspection.

ISO 19840

Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Measurement of, and acceptance criteria for, the thickness of dry films on rough surfaces.

This standard is particularly relevant to protective coatings on rough steel substrates.

ISO 2808

Paints and varnishes - Determination of film thickness.

This standard describes methods for determining coating film thickness.

ASTM D7091

Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals.

This practice is relevant to magnetic induction and eddy current coating thickness measurement methods.

SSPC-PA 2

Procedure for Determining Conformance to Dry Coating Thickness Requirements.

This procedure is commonly referenced in protective coating inspection specifications.

Important: The presence of these standards does not mean that every coating thickness meter automatically satisfies all requirements.

Instrument capability, calibration, verification, sampling and reporting procedures must be assessed for the particular project.

12. DFT Measurement vs Ultrasonic Thickness Measurement

A dry film thickness meter and an ultrasonic thickness gauge are designed for different inspection purposes.

FeatureCoating Thickness MeterUltrasonic Thickness GaugePrimary PurposeMeasure Coating ThicknessMeasure Material ThicknessTypical ApplicationPaint and Protective CoatingsSteel Wall ThicknessMeasurement PrincipleMagnetic Induction / Eddy CurrentUltrasonicCorrosion AssessmentCoating Thickness ChecksRemaining Metal Thickness ChecksExample InstrumentLandtek CM-8826FNSuitable Ultrasonic Thickness Gauge

For industrial maintenance, both types of instruments may be useful.

However, the CM-8826FN does not directly measure remaining steel wall thickness.

13. Choosing a DFT Meter for Steel Structures in Malaysia

Before purchasing a dry film thickness meter in Malaysia, consider the following factors.

Substrate Material

Confirm whether the instrument will be used on steel, aluminium or both.

Coating Thickness Range

Ensure the selected instrument supports the expected coating thickness.

Surface Geometry

Consider flat, curved, narrow or irregular measurement areas.

Surface Roughness

Determine whether the project involves blast-cleaned steel.

Inspection Standards

Review the applicable measurement and acceptance requirements.

Calibration Requirements

Confirm whether formal traceable calibration documentation is required.

Working Environment

Consider temperature, humidity, access and field inspection conditions.

Probe Configuration

An external probe may be convenient for some structural steel applications.

The Landtek CM-8826FN is relevant to users requiring both Fe and NFe capability, subject to confirmation of the actual application requirements.

14. Applications Across Malaysia

Selangor and Kuala Lumpur

Steel fabrication, industrial manufacturing, warehouse structures and engineering inspection.

Johor

Industrial steel structures, fabrication workshops and protective coating inspection.

Penang and Kedah

Manufacturing facilities, equipment structures and industrial maintenance.

Melaka and Negeri Sembilan

Fabricated steel components, manufacturing quality control and coating inspection.

Perak and Pahang

Industrial steel fabrication, engineering structures and maintenance applications.

Kelantan, Terengganu and Perlis

Protective coating inspection and engineering maintenance applications.

Sabah and Sarawak

Industrial infrastructure, steel structures and maintenance inspection.

MTM Precision welcomes enquiries from customers throughout Malaysia.

15. Frequently Asked Questions

Q1. What is DFT measurement?

Dry Film Thickness measurement determines the thickness of a coating after it has dried or cured.

Q2. Can the Landtek CM-8826FN measure DFT on steel structures?

Yes. The Fe function can measure suitable non-magnetic coatings on compatible ferromagnetic steel substrates.

Q3. Can the CM-8826FN measure epoxy coating thickness?

It can measure compatible epoxy coating systems on suitable metallic substrates, subject to the instrument's measurement range and specifications.

Q4. Can the instrument measure multiple paint layers?

It can measure the combined thickness of compatible coating layers above the metal substrate.

It does not separately identify each layer after the full system has been applied.

Q5. Does surface roughness affect DFT measurement?

Yes. Rough or blast-cleaned steel surfaces can influence readings and may require adjustment or correction according to the applicable standard.

Q6. What is the difference between DFT and WFT?

DFT means Dry Film Thickness.

WFT means Wet Film Thickness.

WFT is measured before the coating has dried or cured, typically using a suitable wet film thickness gauge.

Q7. Is one DFT reading enough for steel structure inspection?

Not necessarily. The required number of measurements depends on the inspection area, project specification and applicable standard.

Q8. Can the CM-8826FN measure steel corrosion thickness loss?

No. The instrument measures compatible coating thickness, not remaining metal wall thickness.

Q9. Does using CM-8826FN guarantee ISO 19840 compliance?

No. Compliance depends on the complete inspection procedure, instrument suitability, verification, correction method and acceptance criteria.

Q10. Where can I enquire about Landtek CM-8826FN in Malaysia?

Contact MTM Precision Sdn. Bhd. for technical enquiries, quotation, product selection and availability.

16. Conclusion

Accurate dry film thickness measurement for steel structures is an important part of protective coating inspection and industrial quality assurance.

The Landtek CM-8826FN Coating Thickness Meter supports non-destructive measurement of compatible coatings on steel using its Fe magnetic induction function.

Its external probe configuration and dual Fe/NFe capability make it a practical option for Malaysian manufacturers, engineering contractors and industrial inspection teams working with suitable metallic substrates.

For reliable DFT inspection, users should focus on:

Correct coating and substrate identification

Instrument verification and appropriate adjustment

Surface roughness considerations

Proper probe positioning

Representative measurement sampling

Applicable DFT acceptance criteria

Accurate inspection documentation

A consistent measurement procedure helps support reliable coating quality control and better inspection records.

Contact MTM Precision Malaysia

Looking for a Landtek CM-8826FN Dry Film Thickness Meter in Malaysia?

MTM Precision supplies industrial measuring and testing instruments for steel fabrication, protective coating inspection, manufacturing quality control and industrial maintenance.

For product selection, technical enquiries, quotation and availability confirmation, contact:

MTM Precision Sdn. Bhd. (744811-A)

Telephone: +603-8080 7172

WhatsApp: +6016-660 7346

Email: mtmpre@yahoo.com / enquiry@mtmpre.com.my

Website: www.mtmpre.com.my

Showroom & Service Centre:

No. 29-1 & 29-2, Jalan Bandar 18,

Pusat Bandar Puchong,

47160 Puchong, Selangor, Malaysia.

Business Hours: Monday to Friday, 9:00 AM - 6:00 PM.

We welcome enquiries from Selangor, Kuala Lumpur, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kedah, Kelantan, Terengganu, Perlis, Sabah and Sarawak.

Send us your steel structure coating specification, expected DFT range or inspection requirements through WhatsApp for assistance.

MTM Precision - Your Industrial Measuring and Testing Instrument Supplier in Malaysia.