Incoming components controls
The standard procedure provides physical check and esthetical quality inspection on incoming components. The client is always welcome to ask for additional controls such as water resistance tests on incoming cases or rate accuracy test of mechanical movements.
Assembly of a pre-series test watch
A sample watch is assembled at the beginning of every new series production. This stage ensures that all the technical details are ok (stem length, hands height, …) and we can start mass production without the risk of compromising the entire series.
Dials are fitted manually while Seiler semi-automatic machines are used for hands, having a wide range of modules covering the majority of the calibres from the most popular Swiss movements producers.
We are able to deal with any kind of case construction, from the simplest two pieces with snap caseback to more complicate ones like three pieces top loaded or caseback with screws or screwed.
Casing and crowns assembly are really crucial in order to obtain a high-quality final result.
For these steps we use air ionisers, compressed air and vacuum systems to ensure cleanliness and remove static electricity, as well as the most advanced Seiler machines to cut stems and screw crowns.
Strap and Bracelet fitting
As a final step of the assembly process, we carefully fit precious straps or bracelets paying particular attention to the quality of the final product, that can often be ruined by this very last passage if not executed by expert hands.
Quality Control and Water Resistance Test
Every single timepiece assembled at TAN SA is aesthetically and technically approved after strict controls and tests. Quality controls and water resistance tests (by air and by water) are made on every single watch after the assembly process. Roxer and Witschi instruments are calibrated depending on the water resistance specifications of each model.
Rate Accuracy Test
Quartz watches rate is tested for a minimum of 48 hours in order to ensure that they perfectly run. Automatic watches are wound with special machines before being tested, changing the winding parameters depending on the calibre specifications.
The rate accuracy of each mechanical watch is tested twice with Witschi instruments: when the timepiece is fully wound and after 24 hours. The microphones are calibrated with the number of positions and parameters provided by movement producers. However, the client is always welcome to ask for additional or even stricter tests.
Clients’ control and shipment
In case clients prefer to check their watches before shipment, we have dedicated rooms with all the necessary instruments to carry out technical and aesthetical controls.