18 Dec, 2023

HYT Hastroid Silver Red

HYT Hastroid Silver Red Watch Review

The HYT Hastroid Silver Red, a limited edition of 15 pieces, redefines how we view time. The use of liquids, capillaries and bellows pumps sounds like the work of science fiction, but it is very real and incorporates a sizeable dose of Swiss watchmaking know-how. Mark McArthur-Christie struggles to contain his admiration for this delicious horological creation.

HYT Watch

Watchmakers have a thoroughly undeserved reputation for being a bit quiet, perhaps a little staid – introverted even. History proves that trope wrong time and again. For example, Herr Henlein may have come up with the novel idea of a watch with an hour hand in the early part of the sixteenth century, but since then watchmakers have regularly and joyfully turned up with a different way to tell the time with varying levels of sanity.

Different methods of indicating time

Years before digital watches were a glint in Pulsar’s eye there were mechanical watches with horizontal – and vertical – digital readouts. There have been makers who’ve tried replacing hands with rotating discs and Breguet himself made montres à tact where you felt the time with your fingers. But these are mild amusements in comparison with craziness like bras en l’air watches where pushing the crown causes animated figures on the dial to raise their arms and point – literally – to the time.

The Crow & The Fox pocket watch

Perhaps the peak of this type of creative timetelling was The Crow & The Fox pocket watch conceived and created by Louis Cottier on behalf of Patek Philippe. If you push a button on the top of the crown, the eponymous crow drops a tiny wedge of platinum (of course) cheese from its opening beak, which falls only so far as to indicate the minutes. The fox, meanwhile, sneakily raises his paw to reach for it and, in the process, shows the hour. Unlike the fox in Aesop’s fable, this one never quite snags his cheese breakfast, though.

HYT mechanical fluidic technology

The radical work of Neuchâtel’s HYT, then, shouldn’t come as too much of a surprise. Yet the firm takes the idea of time-telling a stage further. Most non-traditional time-tellers use either mechanical or electronic ways to indicate the hours and minutes. HYT has chosen to subvert all fuddy-duddy mechanisms by replacing hands with fluid – well, the hour hand at least. But this is not simply a fluid-display watch, complicated as that would be to design and build. The HYT Hastroid Silver Red mixes a wholly mechanical movement with a partially liquid display.

To do this, you need quite a bit more than some coloured fluid, a tube and a winning smile. In fact, the HYT system brings together two immiscible liquids, some red dye, an internally-coated, curved 0.8 mm-thin borosilicate glass capillary, a tiny cam, a lever, a set of metal bellows and a thermo-compensator. Try saying that in one breath, let alone conceiving it, designing it and actually making the damn thing.

HYT liquids and capillaries

Let’s start with those liquids. A capillary carrying a liquid and air simply wouldn’t work, so HYT uses two different liquids to create the hour display. Both are naturally clear, so the firm adds a permanent red dye to one. Because they won’t mix, the hour is indicated by their meeting point in the almost circular capillary that runs around the dial edge.

HYT Hastroid Silver Red

You get an idea of how obsessive the HYT watchmakers are when you learn that the coating on the inside of that capillary is one of the most expensive parts of the mechanism. That’s because it needs to be completely transparent as well as being as slippery as a politician’s suit. Even the dye itself is tested for colour fastness over several years.

The mechanical movement makes sure that two tiny, flexible-wall alloy bellows, with walls around 20 microns thin, expand and contract precisely over a 12-hour period, pushing liquid from one to the other.

HYT Calibre 501 CM

Powering the whole show is the Calibre 501 CM movement designed by watchmaker, mechanical artist and materials technologist, Eric Coudray. It’s an almost pocket-watch-sized engine with 352 parts and 41 jewelled bearings (including one at the base of the bellows). Furthermore, the movement is hand-wound, runs at 28,800 vph (4 Hz) and has a 72-hour power reserve.

The bare figures don’t come even close to doing Coudray’s work justice, though. It’s only when you understand what the movement has to do that the magnitude of his achievement becomes clear. If you think about the sheer complication of running a fluid hour indicator alongside a mechanical minute and second hand as well as a mechanical power reserve subdial, it’s not long before your head starts to hurt. Just the basics of keeping the fluid separate from the mechanicals whilst integrating them is ouchy enough.

HYT Hastroid Silver Red

Get into the detail and you’ll need intravenous espresso to keep up. To move the fluid in the capillary just one minutes worth needs a bare 1.5 microns movement of the bellows. By comparison, a sheet of A4 paper is around 100 microns thick. That’s the sort of margin of error that keeps brain surgeons awake at night. It’s also the sort of margin that needs a precisely constant rate of power displacement – hence the choice of the more controllable force that a handwound movement gives.

Then you have to get that power from the movement to the bellows. The transfer of mechanical to fluid motion is thanks to a ‘Coudray Cam’. This cam allows an oversized lever, the ‘sensor’, to transform the movement’s rotational power into linear movement of the bellows and thus the capillary fluid.

HYT Hastroid Silver Red

This all allows the movement to power the bellows (and the fluid inside the capillary they control) so that the hours flow smoothly for twelve hours. Once they reach six o’clock on the dial, the two liquids flow back whence they started, giving a retrograde reading of the next six hours. And that’s another fluid-mechanical feat; the fluid system is entirely self-regulating and, when they are moving in retrograde, the capillary is completely disconnected from the mechanism’s power.

After all that horological cleverness, the movement could be pug-ugly and you’d forgive it. But it’s not. Designed by Coudray, the TEC Group and Prix Gaïa winner Paul Clementi have got involved too. Many of the 352 pieces are black satin finished, laser-treated or bead-blasted. There are details like countersunk edges on the gear train and skeletonisation on the bridges. Even the screws are black-finished so they don’t mar the watch’s appearance.

This new movement is housed in a tank of a 48 mm case that wears smaller than the dimensions suggest thanks to its tapering sides and offset crown. You won’t be doing any weight training though as it’s cut from black coated and satin-finished titanium as indeed is the crown. Everything sits under a coated, domed sapphire crystal.

HYT Hastroid Silver Red