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Hi all, I’m new to this so would greatly appreciate some advice. I bought a used Android/Aragon (small boutique brand like invicta) automatic divers watch. The watches Seiko’s nh35 movement. Unfortunately, it’s losing about 30 seconds a day. I have other automatics but generally they lose/gain only up to about 10 seconds a day, so I feel a little frustrated with this one. I approached a watch repair shop who told me that it would cost more than $200 to service it, which is about double what I paid for the watch. My questions are: 1. Would it be worth me trying to sort this out myself - is there away to adjust the movement to improve the accuracy. 2. Should I just live with it i.e. not worth the effort for a lower level movement. 3. Pay the $200 and get the movement serviced. 4. Explore the possibility of putting in a new movement (same or something like a 6r15) either myself or paying the repair shop to do it. Any advice you can give would be greatly appreciated. I understand there is a subjective element to this, but would like to know what you would do in my position based on your experience. Many thanks

What you need is this lot Sent from my iPhone using Tapatalk

@rogart63 This made me chuckle - we forgot to check scale.... Out of the screws there were two types with the same thread. The problem is the shoulder, one too small and one too big. Original in the middle: I haven't got an broaches only needle files - what are the chances of being able to open the hole to accept the larger shoulder?

Only animals use a drill bit, there certain tools for doing certain jobs. Sent from my iPhone using Tapatalk

Apologies. On the latter method as mentioned I should of said ream out not broach, that's a bit misleading. Also advisable to use a Reamer when setting a new Bushing, rather than a drill bit. The chances of misalignment are greatly reduced. Sent from my SM-G920F using Tapatalk

The way to do it is by the means of a D cutter, if the hole has been elongated there will be half of the hole that has been untouched that is where you line up the cutter so the flat side of the cutter is facing the elongated part of the hole then the cutter will be centred correctly if you know what I mean that’s why the cutters like in a jeweling set have a flat face. Sent from my iPhone using Tapatalk

Not having a Seiko to test I used a 9154 basically something similar. So the timing machine gives all those nice features that you wanted the rate the beat and amplitude. The lift angle is whatever the last watch previously I measured. Then a section from the witschi manual for this machine showing the oscilloscope mode. At around 7.5 ms You'll notice the waveform showing where lock occurs you see a dashed line colored red telling us where the machine thinks lock is occurring. On older watches were the escapement isn't quite as clear cut as a modern escapement I've noticed it moves around a little bit. Then the other thing the timing machines doing is it basically has a window where it perceives this will occur as opposed to looking for a really loud sound which typically is what happens when the escapement locks up and the pallet fork crashes into the banking pin. So when you look at the waveforms of the electric watch it doesn't exactly resemble a mechanical watch. The timing machine still guesses where it perceives lock occurs and you'll notice the amplitude varies depending upon where it guesses. So most of the time it's in the 240 range but you also see a 77 and 143. So the timing machine works for rate but on a non-mechanical lever escapement watch amplitude is not correct. http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&ETA-ESA_9154 http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Seiko_3702B

That's why you have to close the hole to less than the diameter of the pivot and broach out, keeping the hole as round as possible. This work is not fine horology. As Oldhippy would say " Its more like Blacksmithing. " But you can also misalign when Bushing, requires a bit of practice. Sent from my SM-G920F using Tapatalk

isn't it an issue locating the hole properly? In that the above locates based on the existing hole, but if its worn its a bit elongated so its centre location, that a tool will follow, has changed slightly?

In the day, to fit a Bushing or to close the hole with a staking set and broach out both had there advocates, with this type of movement. Both methods lend themselves to an effective repair, obviously the latter being of far less cost. Sent from my SM-T585 using Tapatalk

The correct way to fix this is to broach out the pivot hole, fit a bush then re-establish the hole and oil sink. You will also need to refinish the pivot by filing and burnishing on a jacot tool. You will most likely find guidance on the net by searching for clock pivot bushing. I know there are better links if you look hard, but here is a quick summary http://www.m-p.co.uk/muk/ryoc/doc_page16.shtml I know that some would fit a jewel as it’s quicker and easier, and some would try and punch the edges of the hole to close it up. Neither would be my recommended option!