Wet Film Thickness vs Dry Film Thickness Which One Does UNI-T UT343A Measure Malaysia?
Wet Film Thickness vs Dry Film Thickness Which One Does UNI-T UT343A Measure Malaysia?
Content
When working with industrial paint and protective coatings, two terms frequently appear:
WFT Wet Film Thickness
and
DFT Dry Film Thickness
They are related, but they are not the same measurement.
Choosing the wrong instrument can result in incorrect inspection methods and misleading results.
The UNI-T UT343A Coating Thickness Gauge is used for measuring suitable dry coatings on compatible Fe and NFe metal substrates. It should not be confused with a wet film thickness gauge used immediately after coating application.
What Is Wet Film Thickness?
Wet Film Thickness (WFT) refers to the thickness of a coating while it is still wet after application.
This measurement is normally taken before the coating has fully dried or cured.
WFT measurement can help painting personnel determine whether enough wet coating has been applied to potentially achieve the required dry film thickness.
A common tool for this purpose is a:
Wet Film Thickness Gauge / Wet Film Comb
This is different from an electronic dry coating thickness gauge such as the UT343A.
What Is Dry Film Thickness?
Dry Film Thickness (DFT) refers to the thickness of the coating after it has dried or cured.
DFT is important in applications such as:
Protective coatings
Industrial painting
Powder coating
Steel fabrication
Manufacturing QA/QC
Equipment coating
Metal finishing
A suitable electronic coating thickness gauge can be used to check the final dry coating thickness over compatible metal substrates.
Which One Does UNI-T UT343A Measure?
The UNI-T UT343A is a coating thickness gauge for suitable dry coatings over metal substrates.
Typical applications include:
Paint on steel
Powder coating on steel
Suitable coatings on aluminium
Automotive paint on compatible metal panels
It supports both:
Fe Ferrous substrates
and
NFe Non-ferrous substrates
with a measuring range up to 1750 μm.
WFT and DFT Are Not Interchangeable
A common mistake is to measure a wet coating and assume that this will be the final dry thickness.
As a coating dries or cures, solvents or other volatile components may be lost and the final thickness can change.
Therefore:
Wet thickness ≠ automatically the same as dry thickness
The relationship depends on the coating system and its formulation.
For industrial work, refer to the coating manufacturer's technical data and relevant project specification.
Why Measure WFT During Painting?
WFT measurement can provide early process feedback.
Imagine a painting contractor is applying a protective coating to fabricated steel.
If the wet film is substantially below the intended application level, waiting until the coating has completely cured before discovering the problem may result in additional work.
Checking WFT during application can help the painting team control the process earlier.
Why Measure DFT After Drying?
After the coating has dried or cured, the final coating needs to be checked against the required specification.
This is where DFT measurement becomes important.
A typical process might be:
Surface preparation
→ Coating application
→ WFT check
→ Drying / curing
→ DFT inspection
→ Final QA/QC
WFT and DFT measurements therefore serve different stages of the coating process.
Example: Painted Steel Component
Suppose a factory produces painted steel equipment.
During painting, the operator uses a wet film gauge to check application.
After curing, QA/QC uses a dry coating thickness gauge to inspect several locations.
For example:
Point A: 118 μm
Point B: 121 μm
Point C: 120 μm
Point D: 117 μm
Point E: 119 μm
The final results can then be compared against the required DFT specification.
Powder Coating and DFT
Powder coating is another important application for dry film measurement.
After the powder coating has cured, QA/QC may need to verify the final coating thickness.
Typical products include:
Electrical enclosures
Metal cabinets
Steel frames
Aluminium panels
Machinery components
Metal furniture
Automotive components
A suitable Fe/NFe coating thickness gauge such as the UNI-T UT343A can help perform these final coating checks.
Should You Measure Only One Point?
No single measurement should automatically represent an entire component.
For a large coated panel, take several representative measurements.
For example:
Top Left → Top Right → Centre → Bottom Left → Bottom Right
Then review:
MIN + MAX + AVG + Individual readings
The UT343A provides MAX, MIN and AVG functions, which are useful for multi-point coating inspection.
What If DFT Is Too Low?
If repeated measurements confirm that the dry film thickness is below the required specification, the production or coating team should investigate according to the applicable coating procedure.
Possible areas to review include:
Application process
Coating coverage
Number of coats
Equipment setup
Surface geometry
Process control
The coating thickness gauge identifies the measurement condition.
The corrective action should follow the relevant coating system and project requirements.
What If DFT Is Too High?
More coating is not automatically better.
Excessive coating thickness can indicate process variation and unnecessary material usage, and some coating systems have specified thickness limits.
Always compare results against the actual coating specification rather than assuming that the highest thickness is best.
WFT Gauge or UNI-T UT343A?
A simple selection guide:
Need to measure freshly applied wet paint?
→ Consider a Wet Film Thickness Gauge
Need to measure dried paint or powder coating over a suitable metal substrate?
→ Consider an electronic Coating Thickness Gauge such as the UNI-T UT343A.
Need to measure the actual steel plate or pipe wall thickness?
→ Consider an Ultrasonic Thickness Gauge
These are three different measurement requirements.
UNI-T UT343A Main Features
The UNI-T UT343A offers:
01750 μm measuring range
Fe/NFe substrate support
Automatic substrate recognition
Single measurement
Continuous measurement
MAX/MIN/AVG
199 data storage
μm/mil units
Upper and lower limit settings
It can be used for suitable dry coating inspection in:
Manufacturing | Powder coating | Metal fabrication | Automotive | Industrial painting | QA/QC
WFT and DFT Measurement Equipment Malaysia
Not sure whether you need a Wet Film Gauge, Dry Film Coating Thickness Gauge or Ultrasonic Thickness Gauge?
Send MTM Precision:
Material + Coating + Wet or Dry + Expected Thickness + Application
For example:
"Dry powder coating on steel, approximately 80120 μm, factory final inspection."
This makes instrument selection much easier.
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
Serving coating, manufacturing and industrial customers throughout Selangor, Kuala Lumpur, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kedah, Kelantan, Terengganu, Perlis, Sabah and Sarawak.
22 Sep 2026
