⚙ TESTING & REGULATION

Water Resistance Tester

Applies pressure or vacuum to prove a sealed case still seals.

Regulate Testing & Regulation

Water Resistance Tester — technical drawing

Specification

Types	Dry pressure · dry vacuum · wet pressure
Test range	0.5 – 12 bar typical
Accuracy	±0.05 bar typical on dry units
Cycle time	10 – 60 seconds
Case capacity	Up to 60 mm typically
Display	Digital pressure and leak rate
Power	Mains or internal pump
Test medium	Air (dry) or water (wet)

Technical parameters

Method	Pressure decay or case deformation
Requirement	Crown screwed home
Result	Pass/fail at a pressure, not a rating
Calibration	Against a known pressure standard
Risk	Wet testing lets water into a leaking case

Use magnificationAvoid magnetismVentilate

Overview

A water resistance tester checks a sealed case for leaks. A dry tester pressurises the case with air and watches for a pressure drop, or measures the tiny expansion of the case under vacuum; a wet tester pressurises a small chamber containing the watch over water and looks for bubbles. Dry testing is safer because a leaking watch does not get wet.

The result is a pass or fail at a given pressure — not a certification. A watch rated 100 m and tested at 10 bar today may fail tomorrow, because gaskets continue to age and a case that has been opened once will never be quite as it was. Any test result is a snapshot.

Testing must happen after any case opening, and it must be done with the crown screwed home. A surprising number of "failed" tests are simply an unscrewed crown or a gasket that was pinched during reassembly rather than a genuinely faulty seal.

What matters about it

Proves a seal without submerging the watch
Dry testing avoids water damage on a leaking case
Pressure is set by the operator, not by the watch rating
Results are a snapshot, not a guarantee
Must be done after every case opening

SafetyPressurised vessels store energy and a failing seal releases it suddenly. Never exceed the rated pressure of the tester, never open a chamber under pressure, wear eye protection, and never pressure-test a watch with a cracked or chipped crystal — it will fail by shattering.

Practical notes

Screw the crown home before every test; most failures are operator error.
Test at a pressure appropriate to the watch, not the maximum the machine allows.
A slow pressure decay usually means a pinched gasket, not a bad seal.
Replace gaskets on any watch that fails and retest.

Compatible with

Sealed stainless casesScrew-down and push-in crownsPost-service verificationDive watch testing

Specifications on this page describe generic families and published reference values, not a specific product. Nothing here is for sale, no result is guaranteed, and no page endorses a commercial brand. Follow the documentation for the movement or tool actually in front of you.

⚙ RELATED

Also useful here

Gaskets

Elastomer seals at the back, crystal and crown — what water resistance actually is.

Cases, Dials & Hands

Stainless Steel Case

The housing: seals the movement, carries the lugs, sets the water resistance.

Cases, Dials & Hands

Crown

The control: winds the movement and sets the hands, through a sealed tube.

Cases, Dials & Hands

Timegrapher

Measures rate, amplitude and beat error — the instrument that makes regulation possible.

Testing & Regulation