Accuracy of IWC models

Hello,
I was wondering if other members can post how accurate their IWC watches are and please tell us the model?
I know that there are many COSC watches out there but my favorites have always been IWC watches because, to me, they exude more style. My Aquatimer 2000 has a accuracy of about 1 second per day so thee are no complaints there at all!!
Please also post how regularly you have your wath serviced to maintain this accuracy.
Many thanks and I look forward to the replies.

It's tough to say a watch is "exactly" this precise as it really all depends on how it's worn etc...

That said, on average, my IWC Spitfire Chrono (3717) is about +4 per day.

Point taken. Well I wear my Aquatimer almost 24 hours a day and recently have not been engaged in a lot of physical exercise as I have been too busy at work (medical field).

I have a Mark XVI and accuracy at moment is +0.8 seconds per day in my wrist and +1.5 seconds per day in watchwinder.

Sorry FLAKER,i did buy my IWC in July of 2011 and it is new.

Hello! I have a 2001 GST chrono perpetual calendar and it runs +2 give or take. Pretty good IMO.

Hmm, here goes:
my Top Gun 379901 is at about +1 or +2 secs per day.
my Portuguese Yacht Club 390206 is at about +1 secs per day.
my Portuguese Automatic 500114 is at about +2 or +3 secs per day.
my Portuguese Perpetual Calendar 502303 is at about -2 or -3 secs per day, which is not within IWC specs. Given that its new and needs time to break in, and its movement-complications, I will wait for a bit more before deciding whether to send it in for servicing as it doesn't really bother me.

This below is a comment from a previous discussion on accuracy, by our moderator Michael. As he notes, accuracy depends on a few things.

One of my favourite earlier discussions on accuracy can be found in this earlier thread: what defines accuracy: practicality or ideality ? what is accuracy ? Do we see more than time when we look at our watches, the superlatives ?

My 3 month old 3717 is running ca 3 second fast.

Mine is almost four years old and is still running about the same as your new Mark XVI!

I've been very lucky....

IWC Portuguese Chrono: 0.0 seconds per day on wrist; +1.0 seconds on winder.

Other watches I wear often for comparison:

• Rolex Sub Date: 0.0 seconds per day on wrist; +2.0 seconds on winder.
• Rolex Explorer: -0.5 seconds per day on wrist; -3.0 seconds on winder.
• Tag Carrera Date: +3.0 seconds per day on wrist; +6.0 seconds on winder.
• Tag Aquaracer Day Date: -0.5 seconds per day on wrist; -2.5 seconds on winder.

Correction:

• Tag Aquaracer Day Date: +0.5 seconds per day on wrist; +2.5 seconds on winder.

I am new on this forum. The Portuguese Perpetual Calendar is accurate for more than five centuries! But that might be 'too much,' so I would recommend the Portuguese Chronograph or Yacht Club Chronograph.

I have now had my Big Ingenieur for three weeks, still +11s per 24h. I hope that it improves after that the lubricants has stabilised...
Can the "energy level", meaning how many days left before it stopps have any impact on the accuracy?

Tobiaa

My Mark XVI, purchased in October, 2009, consistently runs 1.4 seconds fast on a daily basis. No complaints here!

Cheers!

Donald

Yes, Tobiaa, the "energy level", as you call it, has a huge effect on "accuracy". Basically, all mechanical movements have what is called "isochronism error" --the tension of the mainspring exerts force as it unwinds which affects the balance. When fully wound, there is much more force; at the end of the winding cycle, the spring is relatively loose and there is much less force. Most watches are adjusted for accuracy when the watch is fully wound.

You can read more about "isochonism" merely by checking Google.

My Pilot's Chrono is consistently running at +4 seconds a day. Although I am not TOO bothered, I couldn't help thinking how I can make it more "accurate" after knowing that other owners with watches using the same or similar calibre can achieve a much better result. A few posts here seem to suggest that the way how a watch is placed when not being worn will affect the accuracy. If so, how should I put it to make it consistently less fast? Any difference between wearing it with left hand and right hand?

Thanks a million!

AL

You need to just experiment. Every watch has slightly different positional variances. Most people try leaving it differently while they're sleeping.

Keep in mind that every second differential equals a .001% difference in accuracy (that is, there are 60 seconds in a minute, 60 minutes in an hour and 24 hours in a day --so we're talking about 1/86,400). As such, even improving a watch by 2/seconds a day really is a miniscule matter.

This has been a very interesting topic. Thanks Shing for making me jealous of your collection' love that Potugese Yatch timer!!!

I last set my Big Pilot (5004) after returning from a trip to Europe on the 16th of July. I always use the atomic clock reference from the Canadian Research Council as my standard (same as what the CBC broadcasts daily at 1pm).

I just checked and I am 5 seconds fast right now. So that's a 5 second gain in 52 days. Very impressive. That is less than .1 second per day by my math (daily it varies much more than this of course).

I've been wearing the BP regularly so it is generally fully wound.

As a very unscientific observation, it seems to be 2 seconds/day fast if it is very fully wound, a little slow if not fully wound, so my current pattern of use seems to be optimal.

Two months ago I bought a Portofino Chronograph IW378302 in Vienna (from Bucherer in Kärnter Straße). Their service was first class, the way I was treated. I just love the look and feel of the watch. I think it's magnificent, especially with the fine gold touches, and so far it's no choice as to whether to wear it or one of my other watches. So I've been wearing it nearly every day since I bought it.

As for accuracy, I've only just started properly checking, even though I've been aware that the watch was gaining. After 8 days of precise checking and a consistent pattern in wearing (and how it's placed overnight when I'm not wearing it), I can say that it is gaining 3.5 seconds per day. Until I read all the comments above, I was getting concerned, but now it seems that the accuracy is well within specs. In spite of that, it bugs me that my humble $90 Timex quartz has gained only 1 sec in the whole 8 days.

Can the IWC Portofino be adjusted finely enough to improve the accuracy, or would any attempt at adjustment make it worse? Is it as good as it can get?

BTW, getting the tax refund on leaving the EU made the final cost of the watch a terrific deal.