GMT 06 by Grönefeld

The GTM-06

The watch differs from other repeater wristwatches in a number of details. This is first and foremost a man’s repeater wristwatch, as one can see in its full bodied and forceful lines.

But there is also an acoustic reason behind this design aspect, as the case volume allows the gongs to develop a full and pure sound. The lugs, which also convey the full outlines of the case to the special galuchat strap, appear to be straightforward but they are not. Using specially developed micro-machining techniques invisible from the exterior, the lugs are specially channeled in order to allow the resonance of the case not to be dampened by their mass.

This is the result of experiments and vast experience that both Tim and Bart developed in the course of years of work on minute repeater mechanisms, as well as careful listening and tuning of the sounds the minute gongs produce. The GTM-06 also utilizes a Cathedral type gong that has a longer winding within the confines of the case, thus providing the fullest possible tone achievable.

The dial is formed by the beautifully finished movement itself, decorated with Geneva stripes, perlage, anglage and perfectly polished screws, hands, indexes and springs. Black polish, the most impossibly demanding and difficult ‘dark art’ of fine finishing found only in the most expensive watches, is used extensively throughout the movement.

Even those areas never to be seen by the user are given exquisite finishing on a level that has become increasing rare in the world of haute horlogerie today. The modern styled chapter ring of black onyx is adorned with highly polished hour indexes that catch the light at every angle to provide a subtle and discrete view of the time. Only the fine finishing of the parts before assembly starts takes more than 2 months of intensive work in several stages to complete.

The watches are available with 18 carat 4N rose gold cases and in 950 platinum. There are plans to develop a unique diamonds set GTM-06 a limited series stealth model in black DLC coated titanium during the course of 2009. Only one unique edition “His & Hers set” will be available. Both will have a minute repeater but the ladies watch will not have the tourbillon mechanism. There are many short, medium and long-term plans to follow as the brand develops and grows.

Scope of delivery
The Grönefeld GTM-06 is delivered in an ultra high-end presentation box of unparalleled quality and design. The hand finished, black piano lacquer box contains two shelves, the uppermost a leather-lined tray with the watch, a comprehensive leather-bound instruction book, guarantee certificate and space for cuff links or other accoutrements.

Below is a special, ventilated wooden tray for cigars. Another level lower, one pushes on the engraved aircraft aluminum inlay with Grönefeld logo, and a secret drawer appears containing a Davidoff (Dupont) black lacquer gas lighter and two cigar cutters.

Servicing and guarantee
Tim and Bart Grönefeld are the owners of QWS, Quality Watch Services BV, a long standing (more than 10 years) and official repair center for a large number of major name watch brands.

With 14 full time watchmakers in employ, the Grönefeld brand is therefore able to guarantee and offer fast, highly expert repair and support to every Grönefeld wristwatch they produce, now and in years to come.

Each GTM-06 is guaranteed against defects in workmanship for a period of 2 years.

Technical Specifications of the GMT 06 by Grönefeld

Mechanical hand-wound movement, Caliber G-01 One minute Tourbillon
Minute Repeater

Movement dimensions
Diameter: 28 mm Thickness: 9.2 mm

Number of parts Number of jewels

Power reserve Balance wheel Frequency Balance spring Main Plate Bridges
Tourbillon: One minute Tourbillon (one revolution every minute) Total weight of the cage 0.420 grams
Black polish and hand beveled on all steel parts Fine regulator on yellow gold engraved indicator Swiss lever escapement

Repeater: Classical mechanism of the minute repeater mechanism
Mechanism is visible through the transparent case back
“Surprise”- and “all or nothing” mechanisms
Two black polished steel hammers striking on Cathedral gongs (extra long gongs)

Casing specifications:

Case
4N rose Gold or 950 Platinum Limited Edition of 10 pieces each Sapphire crystal on the front is slightly domed coated on the inside Sapphire crystal on the back is flat with coating on the inside
Hand engraved case back
White Gold security screws
Polished bezel and centre band with hand-finished straight graining Special channeled lugs to improve the sound of the minute repeater

Case dimensions: Diameter 44mm - Thickness 15.1mm

Water resistance: Humidity resistant, 2 atmospheres – 20 meters – 65.6 feet

Crown: Gold or platinum, engraved with “G” logo

Dial: Open hour- minutes chapter ring made of natural black onyx Internal bezel in white or rose gold printed with minute tracks Grönefeld printed on the onyx
Polished white- or rose gold indexes

Hands: Hours and minutes made in rose gold or white gold with black nickel plating

Strap: Hand-sewn mat black, alligator leather with rose- or white gold triple folding buckle, engraved with the Grönefeld logo

Complete movement:41 jewels 48 hours
Glucydur with timing screws (11 mm diameter) 18’000 vibrations/hour (2.5 Hz)
Breguet overcoil spring

Spotted and snailed rhodium plated nickel silver

Nickel silver hand beveled, Geneva stripes, the underneath spotted Hand engraved gold plated “G” logo on the barrel bridge