How Thick Should Paint and Powder Coating Be? Using a Coating Thickness Gauge Malaysia
How Thick Should Paint and Powder Coating Be? Using a Coating Thickness Gauge Malaysia
Content
How thick should a painted or powder-coated metal surface be?
There is no single thickness value that is correct for every coating.
The required coating thickness depends on factors such as the coating system, substrate, application, manufacturer specification and environmental exposure.
This is why industrial users should not simply measure a coating and ask whether the number is "good".
The correct approach is:
Know the required specification → Measure several points → Compare the results → Identify areas outside the required range.
A portable instrument such as the UNI-T UT343A Coating Thickness Gauge can be used for non-destructive coating checks on suitable Fe and NFe metal substrates.
Why Does Coating Thickness Matter?
A coating is normally applied for a reason.
It may provide:
Corrosion protection
Surface protection
Decorative finishing
Wear resistance
Weather resistance
Product appearance
Process compliance
If the coating is too thin, it may not provide the intended protection.
If it is unnecessarily thick, it may increase material consumption and can indicate that the coating process requires adjustment.
For QA/QC personnel, the objective is therefore not simply to achieve the highest possible reading.
The objective is consistent coating thickness within the required specification.
Paint Thickness Is Not One Universal Number
It is risky to use statements such as:
"100 μm is always correct."
or
"Anything above 200 μm is too thick."
Different coating systems can have very different specifications.
For example, requirements may vary according to:
Primer + topcoat systems
Powder coating systems
Industrial protective coatings
Automotive paint systems
Fabricated steel components
Aluminium products
Always refer to the relevant coating specification, paint manufacturer's recommendation, customer requirement or inspection standard.
How to Check Coating Thickness
A practical inspection procedure can be:
1. Identify the Substrate
Determine whether the base material is:
Fe – Ferrous metal, such as steel
or
NFe – Non-ferrous metal, such as aluminium.
The UNI-T UT343A supports both Fe and NFe applications.
2. Confirm the Required Thickness
Before measuring, know what range is acceptable.
For example, if a particular job specification requires a defined coating range, that becomes the reference for inspection.
Do not create an arbitrary pass/fail limit based only on previous experience with a different product.
3. Measure Several Locations
Avoid taking only one measurement.
For a metal panel, measurements could be taken at:
Top | Centre | Bottom | Left | Right
Suppose the readings are:
122 μm
126 μm
124 μm
123 μm
125 μm
These results indicate relatively consistent coating thickness across the measured locations.
Now compare:
122 μm
126 μm
238 μm
123 μm
125 μm
The unusually high reading should be checked again.
Why Average Thickness Alone Can Be Misleading
Imagine five measurements:
80 | 82 | 81 | 79 | 178 μm
An average value alone can hide an abnormal measurement point.
For coating inspection, it can therefore be useful to consider:
Individual readings
Minimum value
Maximum value
Average value
Measurement location
The UNI-T UT343A provides MAX, MIN and AVG functions, helping users evaluate a group of measurements more effectively.
Powder Coating Thickness Inspection
Powder-coated products are common in:
Metal furniture
Electrical enclosures
Machinery
Equipment cabinets
Fabricated metal products
Automotive components
Architectural metalwork
Visual appearance alone cannot reliably tell an inspector whether the coating has been applied consistently.
A coating thickness gauge provides measurable data that can be compared against the required specification.
Example: Checking a Powder-Coated Cabinet
A QA inspector checks several points on a finished cabinet.
Door: 92 μm
Left panel: 95 μm
Right panel: 94 μm
Top panel: 91 μm
Rear panel: 93 μm
The readings are relatively consistent.
If one area repeatedly measures significantly differently, the inspector can investigate the coating process or component further.
This is more useful than simply looking at the surface and deciding that it "looks thick enough".
Where UNI-T UT343A Fits
The UNI-T UT343A offers a measuring range of up to 1750 μm, allowing it to cover a variety of coating thickness applications.
Key functions include:
Fe/NFe substrate recognition
0–1750 μm measuring range
Single measurement
Continuous measurement
MAX/MIN/AVG
199 data storage
μm/mil selection
Upper and lower limit settings
It can be considered for:
Powder coating factories | Metal fabrication | Painting contractors | Manufacturing QA/QC | Maintenance teams | Automotive inspection
Can a Coating Thickness Gauge Measure Any Material?
No.
A coating thickness gauge must be suitable for the coating and substrate combination.
A conventional Fe/NFe coating thickness gauge should not automatically be assumed suitable for:
Plastic
Wood
Concrete
Glass
Rubber
Every type of coating/substrate combination
Before purchasing, identify both:
1. What is the coating?
2. What is underneath it?
These two questions prevent many incorrect instrument selections.
Coating Thickness Gauge for Factory QA/QC Malaysia
For Malaysian factories, coating thickness measurement can become part of:
Incoming inspection → Production checking → Final QA/QC → Customer acceptance
Instead of relying only on visual judgement, measurement data provides a more objective basis for process control.
The UNI-T UT343A is suitable for users looking for a portable paint thickness gauge or coating thickness meter for compatible metal substrates.
Looking for a Coating Thickness Gauge in Malaysia?
Tell MTM Precision your:
Coating type + substrate material + expected thickness range + application
and we can help determine whether the UNI-T UT343A is suitable.
MTM Precision Sdn Bhd
Showroom & Service Centre: Puchong, Selangor, Malaysia
Tel: 03-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com
Website: www.mtmpre.com.my
22 Sep 2026
