The Patek Philippe 5270R Perpetual Calendar Chronograph combines two classic watch complications into a single timepiece that privileges clarity on the dial. Most Patek Philippe watches reflect the idea of a practical timepiece, but this is something of an exception because the date subdial interrupts two of the three chapter rings, the seconds scale, and the tachymeter scale. There is a complete fractional seconds scale right at the edge of the dial, but it’s not all that easy and intuitive to take an exact reading. And so, considering a subdivision of all watches into two families, “tool” watches on one hand, and watches that are primarily prestigious objects on the other, the Patek Philippe 5270R is unusually closer to the second group. Click here for a selection of perpetual calendar chronographs.
The legibility of the seconds and tachymeter scales at the bottom of the dial is sacrificed to make the date as legible as possible, with large, sporty numerals. The windows for day of the week and month are close together at the top of the dial, and everything is certainly clearly visible, though it’s not a totally logical arrangement. The continuous seconds subdial is on the left, and the chronograph minutes subdial is on the right – it is instantaneous, so moving by one minute at the end of the minute. Below the two subdials – precisely vertically-centred on the centre of the subdial, and horizontally in line with the centre of the date subdial – there are circular apertures for the day/night indicator, which changes at 6am and 6pm, and the leap year indicator, in which the number 4 indicates a leap year. The moon phase indicator has a sapphire disc on which gold moon and stars are applied by means of a vacuum condensation process. It is accurate to one day’s deviation in 122 years.
Case and correctors
The case is a little larger than most Patek Philippe watches at 41 mm, thickness 12.4 mm. Water resistance is the standard 3 atm. The 5270 was first presented in 2011, in white gold and platinum, and this additional piece, 5270R in rose gold with silver-toned opaline dial, was launched in 2015. The crown is used just for winding and setting the time. The calendar indications are adjusted by correctors on the caseband: date correction at 11.30, month correction at 12.30, day of week correction at 10.00, moon phase correction at about 6.30. A special correcting stylus is supplied with the watch.
Manually-wound mechanical movement
The manually wound caliber CH 29-535 PS Q is based on Patek Philippe’s classic chronograph movement presented in 2009, with a perpetual calendar module added to it. The chronograph has a column wheel and a horizontal clutch, so a traditional arrangement when compared to the vertical clutch, but it has been improved by patented gear tooth profiles that reduce wear, improve efficiency and prevent tip-to-tip collisions, all things that are characteristic of the horizontal clutch system. The perpetual calendar module has 182 parts, and is just 1.65 mm thick. The movement runs at 28,800 vibrations per hour, 4 Hertz, with a power reserve of at least 55 hours. The watch is available with solid or sapphire crystal caseback.
Care required during adjustment
No adjustments should be performed on the calendar or moon phase displays between 5.30pm and 2am. This is a long bracket and presumably reflects the moments at which the indications change, starting from the day/night indicator which changes at 6pm. The calendar displays have to be set in a certain order, starting with the leap year indicator (changed by using the months corrector), the date, the day of the week, and the moon phase.
Price and reference
The Patek Philippe 5270R Perpetual Calendar Chronograph costs 145,000 Swiss francs, inclusive of VAT. More information on the Patek Philippe website.