The original Horological Machine N°5 in zirconium was launched at the end of 2012; at the time, we explained that a new series would be presented every year. For the 2013 edition introduced in November, we’ve modified the case to red gold and titanium.
Red gold is significantly heavier than the original zirconium, so this could have been one heavy timepiece… but you probably noticed that we’ve offset the warm gold colour with some cooler (and lighter) titanium components. However, we went a step further: HM5 has an internal container, which protects the movement from shocks and water. Previously in stainless steel, the RT edition’s container is now in titanium. The result? A very different-looking machine, but which retains a comfortable weight.
Aside from this, HM5 RT keeps all the 1970s-inspired ingredients from the original edition. The design cues are from the first supercars like the Lamborghini Miura and Lotus Esprit, as well as the wacky watches of that decade, powered by the first quartz movements.
Technically-speaking, the movement and time display are a unique combination of mechanical and optical engineering: the jumping hours and minutes, situated on horizontal discs in the calibre, are reflected upwards 90 degrees, reversed and magnified 20% by an optical prism in sapphire crystal. Don’t get me started on how difficult it is to craft that prism…
One of the most surprising features of HM5 is what we call the “light convector” system. If the time display seems a bit dim, flip open the flaps on the case. This will let light flow in, through the sapphire crystal window of the inner container, down onto the SuperLuminova of the hour and minute discs.
HM5 RT is a limited edition of 66 pieces. You’ll find a lot more about HM5 on our website, including a fast-paced video with some beautiful 1970s supercars.