Can UNI-T UT343E Measure Small Parts Fasteners and Curved Surfaces Malaysia

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Published: 1 October 2026

The UNI-T UT343E Coating Thickness Gauge can measure suitable coatings on many steel and non-ferrous metal components, but small parts and curved surfaces require extra evaluation.

Even when the coating and substrate are compatible, the reading may be unreliable if the probe cannot sit flat or the component is too small, thin or strongly curved.

Why Component Size Matters

A coating thickness gauge does not measure at an infinitely small point.

The probe and measurement method require a suitable area of metal beneath the coating. If the component is too small, the reading may be influenced by:

Nearby edges
Component curvature
Limited base-metal area
Thin substrate
Holes or threads
Probe misalignment
Movement during measurement

A stable number on the display does not always guarantee that the measurement conditions are suitable.

Can the UT343E Measure Fasteners?

It may be possible to measure some larger fasteners with a sufficiently flat coated surface.

Examples that may provide a suitable test area include:

Large bolt heads
Large washers
Flat metal brackets
Larger nuts with accessible flat faces
Fabricated fasteners with wide surfaces

Small screws, threaded areas and narrow curved heads may not provide reliable probe contact.

The actual part should be tested before the UT343E is selected for a fastener-inspection programme.

Why Threads Are Difficult to Measure

Threaded areas contain:

Peaks
Valleys
Strong curvature
Narrow contact areas
Rapid changes in distance from the substrate

The probe cannot sit flat across this geometry.

A reading on a thread may not represent the actual coating thickness and may vary significantly between positions.

Use an approved alternative method when the coating specification requires measurement directly on threads.

Can the UT343E Measure Pipes?

The UT343E may measure a suitable coating on the outside of a metal pipe if:

The pipe diameter provides an acceptable contact area
The probe can remain perpendicular
The surface is clean
The coating and substrate are compatible
The curvature does not cause unstable readings

Smaller-diameter pipes generally create a greater measurement challenge.

A sample test should be performed using the actual pipe size and coating.

Coating Thickness vs Pipe-Wall Thickness

The UT343E measures the external coating over the metal pipe.

It does not measure:

Pipe-wall thickness
Internal corrosion
Remaining metal thickness
Material loss beneath the coating

For pipe-wall measurement, an ultrasonic thickness gauge such as the UNI-T UT345A is more appropriate.

Some inspection programmes may require both instruments.

Can the UT343E Measure Curved Automotive Panels?

Many vehicle panels have gentle curves that may still allow stable measurement.

For better repeatability:

Choose the flattest available point
Keep the probe perpendicular
Avoid sharp body lines
Stay away from panel edges
Take several nearby readings
Compare equivalent areas
Record the exact location

Strong curvature around pillars, arches and panel edges may reduce repeatability.

Can the UT343E Measure Aluminium Profiles?

Aluminium profiles may include narrow faces, grooves, channels and curved decorative surfaces.

The UT343E may be suitable when the NFE-compatible coating is applied over a section wide enough for the probe.

Before using it for production acceptance:

Test the actual profile.
Identify a repeatable measurement location.
Compare several readings.
Confirm the result using an appropriate reference method.
Document the approved measurement position.

Do not assume that every surface of the profile can be measured equally well.

Edge Effect

Measurements taken too close to an edge may differ from results at the centre of a larger flat surface.

Edge effect may be important on:

Small brackets
Narrow steel strips
Bolt heads
Washers
Window profiles
Metal channels
Cut-outs
Perforated components

Move the probe further from the edge where possible and compare several positions.

Thin Substrate Effect

A very thin metal substrate may affect the measurement response.

Examples include:

Thin sheet metal
Foil
Lightweight stamped components
Thin aluminium sections
Small metal covers

The instrument may display a reading, but suitability should be confirmed using the actual material thickness and geometry.

Do not rely only on the coating range when choosing the gauge.

How to Evaluate a Small Component

Before using the UT343E for batch inspection:

Confirm the coating material.
Confirm the substrate material.
Clean the probe and component.
Perform a reference check.
Choose the flattest available area.
Take at least several readings at the same point.
Rotate or reposition the component.
Compare equivalent parts.
Check whether results remain repeatable.
Confirm the method against the product specification.

If small changes in probe position produce large differences, the component may not be suitable for routine measurement with this probe.

Use a Fixture for Better Repeatability

A holding fixture may help stabilise small components during measurement.

The fixture should:

Hold the part securely
Keep the test area accessible
Prevent rocking
Support consistent orientation
Avoid influencing the measurement area
Allow the probe to contact the surface vertically

The same fixture and measurement position should be used throughout the inspection batch.

Do Not Average Unreliable Readings

Taking many unstable readings and calculating an average does not automatically produce a valid result.

If the probe cannot make proper contact, the correct action is to:

Improve the positioning
Select a better measurement point
Use a suitable fixture
Verify the method with a reference sample
Consider a different probe or measurement technology

Repeatability should be established before the result is used for acceptance.

When a Different Method May Be Required

Another instrument or laboratory method may be necessary when:

The component is extremely small
The surface is sharply curved
The required point is on a thread
The substrate is very thin
The coating is extremely thin
The tolerance is very tight
The part has no accessible flat surface
The coating-and-substrate combination is incompatible
A specific technical standard requires another method

Provide an actual sample or detailed drawing when the application is uncertain.

Who Should Evaluate Part Geometry Before Buying?

Careful evaluation is important for:

Fastener manufacturers
Electroplating companies
Automotive component suppliers
Aluminium-profile manufacturers
Pipe-coating contractors
Precision metal-part producers
Incoming quality-control teams
Supplier quality engineers

Companies in Selangor, Kuala Lumpur, Johor and Penang should confirm the component shape as well as the coating range before selecting the UT343E.

For application advice, send MTM Precision a clear photo with the component dimensions, coating material, substrate and expected thickness.

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

Can UNI-T UT343E Measure Small Parts Fasteners and Curved Surfaces Malaysia