Grönefeld 1969 DeltaWorks

Inspired by the Dutch Delta Works, Bart and Tim Grönefeld, aka ‘The Horological Brothers’, have conceived their first sports utility watch, the aptly named 1969 DeltaWorks which also references the year Bart was born.

The model is designed to cope with the perils of water ingress and shocks while still upholding the elevated standards of horology and traditional craftsmanship that are synonymous with the Grönefeld name.

Grönefeld 1969 DeltaWorks watch

Grönefeld 1969 DeltaWorks


The 1969 DeltaWorks displays hours, minutes and seconds. There is nothing superfluous on the dial to ensure a clear, intelligible format. The hands and hour markers are treated with Super-LumiNova®, which produces a blue glow in restricted light.

Although extremely convenient, this dial is still enriched with numerous details. For example, the hour track sits on a higher plane than the central dial area and small seconds display. The plump lancine-style hour and minute hands deliver impressive readability even in the most challenging conditions. At the fulcrum of the hands, the ‘centres’ are black polished to a gleaming conclusion.

Grönefeld 1969 DeltaWorks watch

The small seconds display features ‘60’, presented in an orange hue, a respectful nod to the brothers’ homeland. Likewise, the country of origin is proudly proclaimed at the base of the dial.


The 1969 DeltaWorks is presented in a 45mm stainless steel case, measuring 12.5mm in height. The case features an integrated strap that ergonomically encircles the wrist, conferring a high degree of wearer comfort while appearing smaller than its stated dimensions would suggest. The scale of the case endows the watch with a generously proportioned dial area, augmenting legibility but without appearing unduly large. Every aspect of the case has been carefully considered.

Grönefeld 1969 DeltaWorks watch

Two inserts are integrated within each caseband, steadfastly secured to the main body of the case. The inserts are offered in two formats: stainless steel, matching the case material, or titanium shrouded in coloured FKM rubber, designed to match the shade of the strap. A notable attribute of the latter option is that there is less risk of the case band picking up annoying scratches. Throughout the composition, the case juxtaposes brushed and highly polished surfaces, contributing to the model’s notable allure.

Grönefeld 1969 DeltaWorks watch

A triple-seal, screw-down crown mitigates the risk of dust or water ingress. In addition, the crown features an ingenious safeguarding system. When the Grönefeld logo on the crown is perpendicular to the dial and pointing upwards, the triple-seal, screw-down crown delivers maximum protection. Both the front and rear side crystals are thicker than normal. As a result of the aforementioned details, the watch is water resistant to 100m.

Grönefeld 1969 DeltaWorks watch


The 1969 DeltaWorks is offered in an array of different coloured FKM rubber straps. The exterior of the strap features a wave pattern, while the inside of the strap is decorated with a motif formed of numerous Grönefeld logos, allowing the wearer’s wrist to breathe.

Grönefeld 1969 DeltaWorks watch

The strap can be cut to length for optimal sizing, while the micro adjustable clasp, featuring gleaming facets and relief engraving, allows the wearer to fine tune the union between the strap and the wrist.

Grönefeld 1969 DeltaWorks watch movement

The sapphire crystal case-back affords views of the beautifully appointed, self-winding movement. The case back features ‘GRÖNEFELD’ and ‘DELTAWORKS’ in relief, while the name ‘Oldenzaal’ is discretely engraved opposite the crown, an elegant reminder of where the Grönefeld family’s watchmaking story began.

When conceiving the 1969 DeltaWorks, Bart & Tim were keen to ensure the watch was suitable for daily wear and compatible with an active lifestyle. With this in mind, they decided it must feature a self-winding movement encompassing the same exalted finishing as other Grönefeld timepieces.

Grönefeld 1969 DeltaWorks Movement

This timepiece houses the calibre G-06, a movement first used within the company’s 1941 Principia Automatic. However, while many elements have been carried over to the 1969 DeltaWorks, there are some additional details which enhance robustness, imbuing this version with its own distinctive character.

For instance, a notable feature specific to this model is the distinctive oscillating weight. The open-worked architecture features four stainless steel arms, presented in a double-spoke design. These arms are connected to an 18K gold mass adorned with a wave motif.

Each of the four arms is positioned beneath the gold mass and projects beyond, sitting above a circular ledge. In case of a sudden shock, the elongated arms will prevent the oscillating mass touching the inside of the sapphire crystal or striking the bridges below.

Grönefeld 1969 DeltaWorks watch

The rotor is completely hand finished and turns on ceramic ball bearings, preventing wear and eliminating the need for lubrication. Meanwhile, the stainless-steel bridges replicate the façades of traditional Dutch houses, termed ‘bell gables’. Each bridge features a micro-blasted central section, framed with a hand-bevelled gleaming edge. Some of the bridges also feature relief engraving.

Each movement is fitted with a plate engraved with ‘ΔW’ (signifying DeltaWorks) along with its unique movement number.

The Grönefeld 5-arm, double spoke gear train wheels exhibit a contemporary character, but their circular grained surfaces pay due reverence to fine watchmaking tradition. Their design, as well as the bevelled escape wheel teeth, prevent the oil from dissipating, thereby mitigating wear. The free-sprung balance mitigates positional influence and delivers superior rate stability. The escapement is adjusted to heat-cold, isochronism and six positions.

Grönefeld 1969 DeltaWorks watch

Gold chatons stand testament to the no-compromise specification of this movement. In addition, the mirror polished screws feature chamfered rims and slots. Numerous surfaces gleam, courtesy of the mirror-polishing which has been patiently executed by time-served hands. The inventory of different decorations includes snailed, grained, spotted and frosted surfaces.


The 1969 DeltaWorks is available with 3 different dial designs/colours, 5 different strap options and, finally, a choice of stainless steel inserts or colour-coordinated FKM rubber-clad inserts.