How Thick Should Powder Coating Be with UNI-T UT343E Malaysia

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Published: 1 October 2026

There is no single correct powder-coating thickness for every product. The required thickness depends on the powder type, substrate, service environment, appearance, customer specification and coating manufacturer’s recommendation.

The UNI-T UT343E Coating Thickness Gauge helps factories measure the cured coating and compare it with their approved upper and lower limits.

Do Not Use One Thickness for Every Product

Powder-coated products may require different thickness ranges according to:

Indoor or outdoor use
Steel or aluminium substrate
Corrosion-resistance requirement
Decorative or protective purpose
Powder chemistry
Number of coating layers
Component geometry
Customer specification
Applicable project or product standard

The correct acceptance range should come from the approved technical requirement—not from a general internet value.

What Is Dry-Film Thickness?

After powder has been applied and cured, the remaining solid coating is known as the dry film.

Dry-film thickness is normally expressed in:

Micrometres: μm
Mils: Commonly used in some specifications

The UT343E can display measurements in μm or mil, allowing the operator to work with different specification formats.

Why a Coating May Be Too Thin

Insufficient powder-coating thickness may result from:

Low powder output
Excessive spray distance
Fast gun movement
Poor grounding
Difficult component geometry
Inadequate coverage at edges
Incorrect voltage or current settings
Poor line speed control
Missed or shadowed areas
Inconsistent operator technique

A thin coating may reduce coverage, appearance or protection depending on the product requirement.

Why a Coating May Be Too Thick

Excessive thickness may result from:

Too many spray passes
Slow gun movement
Excessive powder output
Coating build-up at corners
Recoating or touch-up work
Poor process control
Incorrect line speed
Heavy application on easily reached surfaces

More coating is not automatically better. Excessive thickness may increase powder consumption and create finishing, curing or dimensional problems.

Measure More Than the Flat Centre

The flat centre of a component is often the easiest area to coat and measure, but it may not represent the entire product.

Check locations such as:

Flat centre surfaces
Corners
Sharp edges
Recessed areas
Welded sections
Holes and cut-outs
Upper and lower faces
Areas facing away from the spray gun
Touch-up locations

A component may show acceptable thickness in the centre but insufficient coverage at an edge or recess.

Use the Correct Substrate Mode

Select the measurement method according to the base metal:

FE mode: Powder coating over steel or iron
NFE mode: Powder coating over aluminium or another compatible non-magnetic metal

The UT343E can identify the substrate automatically or allow manual selection.

If the material is known and every component in the batch uses the same substrate, manual selection can help maintain a consistent inspection procedure.

Check the Instrument Before Measuring

Before inspecting the production batch:

Clean the probe.
Select the appropriate reference plate.
Check the uncoated plate.
Place a standard coating film on the plate.
Take several readings.
Confirm that the results are stable.
Clean and dry the coated component.

Do not use production readings for acceptance decisions if the gauge repeatedly fails the reference check.

Take Several Readings per Component

One reading cannot represent the complete coating condition.

A practical inspection may require:

Several readings on each component
Multiple components from each batch
Measurements from different rack positions
Checks at the start, middle and end of production
Repeat inspection after process adjustment

The sampling plan should be documented so results from different batches can be compared consistently.

Use Minimum Maximum and Average Values

The UT343E can display:

Minimum thickness
Maximum thickness
Average thickness

These statistics help the quality-control team understand the coating distribution.

However, an acceptable average does not mean every measurement passes. If the specification requires a minimum thickness at every critical point, an individual low reading may still require investigation.

Set Upper and Lower Limits

Enter the approved powder-coating limits into the UT343E.

The LED and audio alarm can then indicate when a reading is:

Below the selected minimum
Within the selected range
Above the selected maximum

This helps operators check multiple components more efficiently.

The limit settings should be verified whenever the product, powder, customer or coating specification changes.

Investigate Trends Across the Production Line

Digital records can reveal whether a thickness problem is random or systematic.

For example:

Readings gradually decrease during a shift
Components at one rack position are consistently thinner
Corners are always thicker than flat areas
One operator produces greater variation
A particular supplier’s parts show different results
Thickness changes after equipment adjustment

The UT343E stores up to 3300 readings and supports Bluetooth App and PC data analysis for more organised inspection records.

Coating Thickness Is Only One Quality Check

An acceptable thickness reading does not confirm every aspect of coating quality.

Depending on the product specification, additional checks may be required for:

Adhesion
Colour
Gloss
Surface appearance
Curing
Hardness
Impact resistance
Corrosion resistance
Porosity
Coverage at critical locations

The UT343E measures coating thickness; it does not replace these other inspection methods.

When Readings Vary Too Much

If measurements show unexpected variation:

Repeat the reference check.
Clean the probe and component.
Confirm the substrate mode.
Repeat the reading at the same point.
Measure nearby areas.
Check other components from the batch.
Review the powder-application process.
Record the locations of high and low readings.

Do not adjust the production process based on one questionable measurement.

Who Should Use the UT343E?

The UNI-T UT343E is suitable for:

Powder-coating factories
Metal fabrication companies
Aluminium product manufacturers
Automotive component suppliers
Electrical enclosure factories
Production quality-control teams
Incoming inspection departments
Coating contractors

Factories in Selangor, Kuala Lumpur, Johor and Penang can use it to compare actual coating thickness with their approved production limits.

For assistance selecting a powder-coating thickness gauge, send MTM Precision your substrate material, expected thickness range and product photo.

MTM Precision Sdn Bhd
Showroom & Service Centre: No. 29-1 & 29-2, Jalan Bandar 18, Pusat Bandar Puchong, 47160 Puchong, Selangor, Malaysia
Tel: 03-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com
Website: www.mtmpre.com.my

How Thick Should Powder Coating Be with UNI-T UT343E Malaysia