The Signalman tecnical details can be downloaded or you can print a PDF of these details here;
The case body used on the Signalman model is a patented four part outer assembly consisting of the visible stainless steel components. And a two part anti-magnetic movement holder. The case is extremely complex and expensive to manufacture, machined to tolerances not exceeding 0.01mm.
Case dimensions are 15.01mm from the case back to the crystal. 44mm outer case diameter, excluding the crown. 47mm wide including the crown. 51mm from lug tip to lug tip. Strap width at the lug ends is 24mm. The lugs wrap around the wrist, dropping below the case by 4mm making the watch very comfortable on both large and small wrists.
The screw in, double gasket crown is 9mm in diameter, giving great leverage, making it very easy to use. The pusher for setting the GMT sub-dial is unusually built into and through the lug assembly. The strap fitting bars are a two piece screw together assembly with large 3.5mm screw heads and 2mm bars. This gives superior support and strength while reducing wear to the straps.
The Sapphire Crystal is 2.20 mm thick with an anti-reflective coating on the inside where it won’t get rubbed off. The crystal is set just below the lip of the bezel. The Schofield Signalman is a robust and elegant watch with a water resistance of 500 metres.
The anti-magnetic movement assembly consists of the dial and a special one piece movement holder. This group of components helps keep magnetic flux away from the movement by providing a preferred path for the magnetic field to pass through.
The Signalman DLC has the stainless steel parts of the case coated with black Diamond Like Carbon. This is the hardest and slickest of coatings available. The case parts that are DLC coated are first microbille finished which gives a matt look. The crown and case back are left polished and uncoated.
The case back is a screw down type, featuring an etching of Smeaton’s lighthouse and a stylised graphic of a Fresnel lens. The engraved lettering tells of some of the model’s details.
The Signalman case design is representative of the early Aldis lamps used by the Royal Navy, and the casements of some Fresnel lenses.
The Signalman DLC is the same as the polished version in every way apart from the near black case. It is limited to just 100 pieces.
DLC is an abbreviation for Diamond Like Carbon, a special coating applied to the stainless steel case components of the Signalman DLC.
The coating process takes place in a facility in Germany that produces a superior hydrogen free DLC that is especially hard and consistent in colour.
As the name implies DLC is similar to diamond but has a different crystaline structure. Applications are typically those where it is needed to reduce abrasive wear. As a coating it is only a few microns thick, blasted on to the substrate material in a special chamber. The resulting surface finish has many desirable qualities that makes it superior to more common PVD coatings.
DLC is extremely hard (4500 HV) compared to untreated stainless steel (225 HV) and its been shown that if you were to knock the watch, this ‘skin’ would flex slightly, greatly reducing the risk of cosmetic damage.
DLC is also slicker than Teflon. It has a Coefficient of Friction around 0.03 where the surface of steel is 0.78, that is a big difference. It feels very smooth, is extremely water resistant and antibacterial.
The Signalman GMT PR model wrist watches uses the very high end mechanical, automatic, Swiss made Soprod 9335/A10 movement. This is the base Soprod Alternance 10 Calibre (A10) movement with the 9335 module placed on top to handle the Power Reserve and the GMT complications. Movements are regulated in 4 positions insuring an average deviation of +/- 4 seconds a day. Watches are therefore 99.98% accurate. These Soprod movements are beautifully finished and decorated using traditional Swiss methods such as Côtes de Genève, Perlage, blued screws and Rhodium plating.
Round calibre 111⁄2’’’ Diameter: 25.60mm Height: 5.10mm Automatic winding in 2 directions 28’800 alternations per hour (4Hz) Number of jewels : 31
3 central hands; Hours, minutes and seconds 24 hour indicator at 6h Power Reserve Indicator at 12h Date with aperture at 3h The timing of the 31 jumps of the date can be between -/+ 10 minutes from midnight 24h Crown at 3h with 3 setting positions Push setting for 24 hour hand at 4:30h
Rotor with ball-bearings Mechanism with the integrated automatic device Regulator assembly with a device of fine regulation Shock–absorber: Incabloc
A static test (movement only, not cased up and held motionless) give results of ± 4 s/day. Realistic cased up dynamic test results should be ± 4 s/day - ± 10 s/day i.e. when worn.
Inside diameter of the barrel drum: 10.98 mm Diameter of the core: 2.43 mm Available height for the spring: 1.05 mm
Height: 1.00 mm Thickness 0.122 mm Length: 3:80 mm Moment of force M0 780 g mm Moment of force M24 610 g mm Development in turns 7.7 tours The barrel makes one turn in 5h 37m 30s Type: Nivaflex NM
Minimal power reserve: 42 h movement run down bettween 42 and 48 hours
Distance: pallet – balance: 2.95 mm Distance: wheel – pallet: 2.797 mm Lift angle of balance: 47° MHVJ made
Number of teeth: 20 Total diameter: 4.85 mm Hole diameter: 0.33 mm Diameter of pivot: 0.092 mm Between shoulders :1.77 mm Escape wheel, steel, épilame-coated, DTH lube
Lift in ruby monocrystal épilame-coated Diameter of the pivots: 0.09 mm Between shoulders: 1.05 mm MHVJ made
Balance wheel: Glucydur gilt – 4 arms Staff: épilame-coated Moment of inertia: 8 mg cm2 Total diameter: 8.98 mm Hole diameter: 0.80 mm Height of the felloe: 0.41 mm Thickness of the arm: 0.20 mm Length of the axle: 2.49 mm Diameter of the pivots: 0.072 mm Height of the plate: 0.75 mm Distance of the impulse pin: 0.68 mm Diameter of the plate hole: 0.33 mm MHVJ made
Flat no. CGS 0.950
Positions: CH, FH, 6H, 9H, 3H Middel rate 0h: ± 4 s/d Max. divergence all positions 0h: 15 s/d Isochronism CH 0h – CH 24h: ± 15 s/d
Screws: untreated unless specified as blued Plates: perlage Rotor: Côtes de Genève, un-branded Barrel: radial spiral Rachet wheel: radial spiral Rhodium plated
The dial is a 2 part brass construction, rivetted together. Coated in copper oxide matt black paint. The inner dial is further engraved for the GMT index. The GMT and minute indices marry up perfectly, the GMT 12 o’clock noon aligning with the 6 o’clock on the main index.
The applied, diamond polished hour markers are fixed to the dial using tiny pins. The non-numerical hour markers are hollowed and filled with SuperLuminova C1, the whitest and brightest lume.
Designed with minimalist symmetry, there is no printing on the dial that is unnecessary. The slashed O at the 12 o’clock position is congruent with the 24 hour GMT display and military time. The slashed O is also used for clarity as it cannot be confused with any other symbol.
The power reserve indicator is designed to resemble a lighthouse beam of light, this general shape is echoed thoughout the watch, i.e. the hands and hour markers. The beam of light has now been adopted formally as the Schofield logo.
The minute and hour hands are diamond polished and again filled with SuperLuminova C1.
The second hand has been designed with a large black central cap that hides the canon pinion and is an unusual feature in wrist watches. The counterpoise of the second hand is of the same dimensions as the counterpoise of the GMT hand but is instead solid.
The date window is deliberately small and inconspicuous so as not to clutter the dial.
All Schofield straps are manufactured using top quality materials from around the world. We use special leathers and exotic fabrics and often create limited edition straps. The strap insert is custom made for Schofield and is fabricated in the classic half Remborde method. All of our straps are lined with fine green calf skin and feature a patented red ‘keep close’ ribbon that prevents the floating keeper loop from moving up the strap.
Some of the materials we use for our straps are water resistant to 100 metres, for example, the sharkskin, horse leather and india-rubber.
We are constantly updating our catalogue of straps in innovative and sometimes unusual directions. We aim to use non-synthetic materials for all our straps where possible and have a limited edition range of straps made with English fabrics.
The buckle is the only component of the Signalman GMT PR that has not been designed by Schofield as it fitted the bill perfectly. All buckles have been engraved with the name of the company and are made with polished 316L Stainless Steel.
Changing the straps is achieved by using 2 x 2.5mm screwdrivers.
Changing the buckle uses a 1.6 mm screwdriver.
A strap changing tutorial is available on youtube and we provide adhesive lug protection on request. Various strap changing accessories are available at the Schofield shop including an all-encompassing English made strap-changing kit.
The Signalman Box is manufactured and finished by hand by skilled craftsmen in the North of England. They are made with solid Cherry and based on turn of the century marine chronometer boxes. The scaling and dimensions of the box are based on the mathmatics of the ‘Golden Ratio’. Each box features custom made brass work and is badged with the serial number of the corresponding watch. The Signalman DLC comes in exactly the same box as the Signalman but has been finished in a black laquer.
Inside the box is a CNC milled foam insert, the brass GMT Setting Pusher and chamois leather. We take as much pride in the less conspicuous areas of the business as we do with the product. This is exemplified in the stationery and packaging we use. All our paper is made from 100% cotton, and is the finest produced in England. The envelopes, labels, tags, stickers and stamps are also sourced in England from the best manufacturers. In spite of this we try to keep our packaging as utilitarian as possible.
All printing and foiling is carried out in England. Nearly all of our packaging is recyclable.