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Tudor 79170 Big Block; The only chronograph you will ever need?

Lets make it clear from the start; I am a huge fun of the Tudor brand; their heritage, their history and their offerings. The Tudor name first appeared in 1926 and it was registered as an independent company in 1946. Hans Wilsdorf, the founder of Rolex, wanted the Tudor watches to be obtainable for a lower price than their Rolex siblings but still benefit from the same quality. This was possible by using Rolex oyster type cases equipped with off the shelf reliable movements form ETA, Valjoux etc.

Tudor 79170 Big Block

A lot of people consider Tudor as the choice of those who would like a Rolex but could not stretch the budget far enough. I beg to differ. While they did present a more affordable opportunity, they also had a number of firsts in the Rolex family beginning with the Advisor, the only mechanical alarm watch between both brands and continuing with the first and only manual wind Submariner, a watch extremely rare and very desirable by collectors. But for me, their most important achievement was that they were the first Rolex family brand to introduce an automatic chronograph back in 1976, a good 12 years before Rolex adopted a modified version of the El-Primero movement for their Daytona. This first automatic chronograph will be discussed in today’s post.

Tudor introduced their first chronographs back in 1970. They utilised hand wind movements such as the valjoux 23 and they featured some very nice colourful dials encompassed by oyster cases with nicely chamfered lugs. In 1976 the company decided to embrace the new trend and introduced their first automatic chronograph using the valjoux 7750. The case was similar to the one used by their predecessors but had gained a bit in thickness in order to accommodate the rotor of the automatic movement. These cases are now known as big blocks and these models enjoyed a very long life stretching all the way to the end of 1995.

Tudor Big Block and Speedmaster TinTin

During their introduction, the company decided to offer some black and blue dials commonly known as monte carlos or exotics and introduced for the first time some panda, reverse panda and albino dials. The blue monte carlos where offered with steel or blue tachymeter bezels and blue 12h graduated bezels. The black monte carlos where offered with steel and black tachymeter bezels and black 12h graduated bezels which were also the available choices for the new panda, reverse panda and albino dials. The above combinations paired with some short-lived square-guard cases leave a potential buyer spoilt for choice. The monte carlos lived a short life and are currently commanding a great appreciation in collector circles. This is reflected on their price which is now creeping above £10000. The albino dials are also quite rare but they seem to be trading below the panda and reverse panda versions. A complicated world, I know, but the internet is full of information that will help navigate a potential buyer.

Exotic Big Blocks

If you are into chronographs I am sure you have come across the Rolex Daytona 6263. An iconic watch that can probably be considered as the archetype of well-designed chronographs. It had always been on my radar as a future purchase until I came across one and had the opportunity to strap it on my wrist. Dream shattered… I couldn’t believe how underwhelmed I felt. It felt quite fragile and flimsy and at 36mm it looked tiny and out of place on my 6 and ½ inch wrist. It is one of these rare occurrences where a watch looks better in the pictures rather than in real life! I loved the aesthetics but not anything else and this meant that I had to look at other alternatives.

The big block was exactly what I was looking for. A 40mm oyster cased chronograph with a date. What else can someone ask for? As was mentioned above, someone in the market for a big block is faced with a lot of choices. I have always admired the sunburst panda dial but I felt that the reverse panda would be much more versatile during everyday use. I knew that I did not like the steel bezel so I had to decide between the tachymeter black bezel or the 12h rotating graduated one. Unless someone is a racing driver or a production engineer working on an assembly line the second choice seems like a much more useful feature. With all of these out of the way I started looking for a 79170. Examples were plentiful but most of them had lost their most prominent feature, the lug chamfers, due to previous polishing. A small number of examples also seems to be suffering from tritium deterioration.

Tudor Big Block Chamfers

All big blocks should feature a Rolex Triplock crown and the caseback should bear the “original oyster case by Rolex Geneva” inscription accompanied by the Rolex Crown. If someone scrutinizes a number of examples will notice a few differences between watches produced during different eras. The applied dial markers are mostly chamfered but models with plain indices can be found. Most big blocks bear the Oysterdate designation underneath the Tudor name but some don’t. The date window is usually framed by a printed rectangular but not on all examples. The radial pattern found on the subdials of the last versions seems to be different to the one found on the earlier versions. Such small differences are quite common and no watch should be dismissed as a fake without careful scrutinising. The reference number for the original big blocks was 94XX which was then changed to 791XX for the last generation.

After a few weeks of searching I managed to source a nice example from a fellow collector. As soon as I received the watch I could finally see what all the fuss is about. The watch had a reassuring heft on it and it felt amazingly well built. The fully brushed oyster bracelet was a great match and the chamfered lugs helped a lot with the transition from the radially brushed lugs to the highly polished case sides.

Tudor Big Block on Oyster Bracelet

My example is a B37XXXX serial which means that the watch was produced around 1991. The mate dial gives it a no-nonsense toolish look and does not attract any weird reflections. The applied indices are clearly visible under different angles and lighting conditions due to the chamfered edges. The hour and minute hands never seem to blend with the colour of the dial due to their design; sloping downwards from the highest point in the middle to the lowest on the edges. The chronograph seconds hand has a very well defined, white arrow shaped tip and the rest of the functions are clearly visible due to the reverse-panda colour scheme. The date function is a welcome bonus for me and manages to nicely balance the 12-9-6 arrangement of the valjoux 7750. The movement can easily be dismissed as a pedestrian choice but please remember that some of the most well-known brands such as IWC, Breitling and Sinn depended on it for years due to its reliability and accuracy. The 12-h graduated bezel can be used to easily track a second time zone or track different activities without engaging the chronograph. The watch looks amazing on the oyster bracelet but also works wonders on a distressed or racing leather strap.

Before receiving the watch, I was not really sure on how I would feel about it. When it finally arrived, and as soon as I had it on my hand and around my wrist any shadow of doubt completely disappeared. It really is an amazing chronograph and I still find it better looking and proportioned than any Daytona model, past or present. The fact that it goes well with leather straps and NATOs is an added bonus! Prices now seem stable around the £4k mark but well-preserved, unmolested examples are quite rare. If you can get your hands on one of them, pull the trigger and you will not be disappointed.


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