Knocking a watch out of regulation

njburke

Hi.
I got a new watch a few weeks back which I've been wearing everyday. It's a Seiko 5 srbp17, it has a 4r36 movement. Anyway, I gave it a good knock over the weekend, I bent the springbar and the bracelet uncoupled. I was changing the sheets on the kids bed and I caught the bedpost with the watch.
As the watch was relatively new I had been running the watch check app against it, it was performing very well about +2s/d. Since the knock it's now at +40 s/d, for the last three days.

What has happened to the mechanism, what has changed with the balance wheel?

My new watch doesn't seem to be up to the hiding my old Seiko monster took.

Some of the entry-level Seiko movements had a design weakness whereby an unlucky impact could cause the hairspring to jump out of position and perhaps tangle slightly. The crude fix was to give it another slap on the palm of your hand (!).

I don't know if that's the case with yours because a tangled hairspring usually manifests itself as running massively fast (not just a few tens of s per day). Also I was under the impression the 4R36 had a change to mitigate this issue.

Whatever the issue is, a watchmaker should be able to sort it for you. Although for a new watch and 'only' +40s/d I might just tolerate it for a few years until a service is more timely.

Trigger Happy

I would chance my arm and see if you can get it sorted under warranty. Watches should be able to tollerate some amount of knocking.

Trigger Happy

Trigger Happy wrote: »

I would chance my arm and see if you can get it sorted under warranty. Watches should be able to tollerate some amount of knocking.

The impact was sufficient to break the strap off. So it was a 'good knock' as the OP says. That falls under accidental damage, not the normal wear & tear a mechanical watch is reasonably expected to tolerate.

(In 9/10 cases a workhorse Seiko movement probably will take a good knock and come out unscathed. But that's good fortune and it doesn't mean the 1/10 case is covered under warranty)

njburke

I'll see if runs consistently fast over a couple of weeks. If it stays at a constant rate, I might have a go at regulating it.
Warranty isn't really an option, I bought from jomashop, I imagine a warranty return is a PITA, besides I did give it a wallop.

saccades

[Deleted User] wrote: »

Some of the entry-level Seiko movements had a design weakness whereby an unlucky impact could cause the hairspring to jump out of position and perhaps tangle slightly. The crude fix was to give it another slap on the palm of your hand (!).

I don't know if that's the case with yours because a tangled hairspring usually manifests itself as running massively fast (not just a few tens of s per day). Also I was under the impression the 4R36 had a change to mitigate this issue.

Whatever the issue is, a watchmaker should be able to sort it for you. Although for a new watch and 'only' +40s/d I might just tolerate it for a few years until a service is more timely.

4R36 is a modified 7S, there is a stop added to retain the bit that used to escape as well as the hacking function.