Jump to content

Recommended Posts

Posted (edited)

Hello all,

I want to strip down and service my favourite Seiko 5 watch. Thing is I'm a newbie and Odds on I'll probably make mistakes. I'll be using various Vids off Youtube to guide me but if something does go wrong I might want to replace the entire movement as I'll possibly not be able to find the fault. I looked online and it dont seem you can buy replacements brand new. I was thinking about the NH36 movement as a replacement as they're readily available although what worries me is it's thicker and might not fit my watch case.

I'd welcome and be grateful for any advice.

17322308997196827821360039176626.jpg

Edited by Ruffass
Posted

Don't know where in the world you are but 7S26 movements are still available, not cheap compared to what you can get a complete Seiko for.

It's common practice to use the NH36 as a replacement but you'd need to swap the day wheel from the 7S26.

image.thumb.png.074e07279fe39da34fbc0807dc4775e1.png

  • Like 1
Posted

Thanks for your reply Andy

I'm in Sheffield UK.

I was hoping to be able to get a replacement movement for around £35.

Not cost effective otherwise as like you say I may aswell get a new watch.

I think if things go wrong I'll just have to try and convert it to the NH36 movement which seems much cheaper.

 

 

Posted

iirc you’ll likely have to swap the plastic ring that comes as part of these movements, black ring on the 7s26 and grey on the NH36 as well.

 

Tom

  • Like 1
Posted
8 hours ago, tomh207 said:

iirc you’ll likely have to swap the plastic ring that comes as part of these movements, black ring on the 7s26 and grey on the NH36 as well.

 

Tom

Thanks Tom,

I was wondering if you have any experience doing this Conversion, maybe you could give me some advice if and when the time comes?

I would also be grateful if anyone could give me a pointer in the right direction in regards to obtaining genuine Seiko parts that sells to the UK public (not trade). A parts catalogue may come in handy aswell? I'm thinking for a new crown and stem. 

Posted (edited)
11 minutes ago, Ruffass said:

Thanks Tom,

I was wondering if you have any experience doing this Conversion, maybe you could give me some advice if and when the time comes?

I would also be grateful if anyone could give me a pointer in the right direction in regards to obtaining genuine Seiko parts that sells to the UK public (not trade). A parts catalogue may come in handy aswell? I'm thinking for a new crown and stem. 

Cousins will deal with anyone but as Trade (so you don't get the same customer rights or something)
but it's never bothered me and I've only ever had 1 issue that was resolved without question.

I you looking at genuine parts for replacing on the 7S26?

Edit

Is it a 7S26-0480?

 

Edited by AndyGSi
  • Like 1
Posted

Thanks again Andy.

When I tried signing up online they wanted me to confirm I had my own business. I also think they wanted a VAT number. Not sure if and how to get round that? 

Posted

I haven’t done the conversion myself but have seen plenty of info online in doing this. Happy to help if I can though. I echo Andy about cousins, there are also HS Walsh along with Gleaves. Worth checking all three for price as sometimes one can be cheaper than the others.

i wasn’t ask for a vat number when I signed up for cousinsuk, it was fairly straightforward.

 

Tom

  • Like 1
Posted

Thanks Tom, I've just had a look and it turns out I've successfully obtained an account with Cousins. I'll try them for the relevant parts.

Thanks, Ruffass 😊

1 minute ago, RichardHarris123 said:

I think I was asked for a business address and vat number, if I remember correctly, I  left it blank and I was allowed to join. 

Cool, cheers for that Richard.

1 hour ago, AndyGSi said:

Is it a 7S26-0480?

Sorry just seen this edit! Yes it is Andy, and there's an F in a box next to this Number.

  • Like 1
Posted
1 hour ago, Ruffass said:

Sorry just seen this edit! Yes it is Andy, and there's an F in a box next to this Number.

The crown would be a 9M40B3SNW0 and the F relates to the case construction as below.

image.thumb.png.33fbabccf6d1dda6cce52b65967371e6.png

  • Like 1
Posted
45 minutes ago, watchweasol said:

Hi Ruffass. Ther are also A.G.Thomas ( Bradford). And H.W. Walsh who are also material houses who deal amateur’s.

Thanks watchweasol. 👍

 

28 minutes ago, AndyGSi said:

The crown would be a 9M40B3SNW0 and the F relates to the case construction as below.

image.thumb.png.33fbabccf6d1dda6cce52b65967371e6.png

Thanks for the info Andy. Although I've had a quick google and it seems it wont be a straightforward job. I think the problem might be getting the stem and crown right. I might be better just trying to service the 7S26 and see how I go. I'll make a note of the Part number just in case. 👍

Posted

I've done this swap and its very easy. You will need to replace the stem, since the NH has hand winding. Well worth the mod. It swapped in no problems. I cant remember if I had to change the spacer ring. 

Posted
3 minutes ago, SwissSeiko said:

I've done this swap and its very easy. You will need to replace the stem, since the NH has hand winding. Well worth the mod. It swapped in no problems. I cant remember if I had to change the spacer ring. 

Hi there SwissSeiko. Thanks for the info. Oh right so do I put the Original Crown on the new NH36 stem? Did you do the swap on the same model as mine (SNXS73)? Is there any cutting to size required? 

Many Thanks in advance! 😊👍

 

1 hour ago, AndyGSi said:

The crown would be a 9M40B3SNW0 and the F relates to the case construction as below.

image.thumb.png.33fbabccf6d1dda6cce52b65967371e6.png

Thanks again Andy. I've just ordered the part from Cousins. £12 including P+P.👍

Posted
29 minutes ago, Ruffass said:

Is there any cutting to size required?

No cutting required but if you do go for the NH36 you're best going for a NH36-3.8 so you don't have to mess around with the Day Dial.

  • Like 1
Posted

Cheers Andy. Yeah I got the 3.8 NH36 coming from Ali Express. Only cost £25 in Black Friday Sale. Supposed to be Japanese but you never know. Hope it performs like a couple of my other NH35 Japanese movements which I've got in  Addiesdive and a Cestrian watches. 👍

  • Like 1
Posted

I did the 7S26X - NH family swap a few years back. First time I had done such a thing, so I was likely in a similar state of skill as you are currently. I had an old gray market 5 that bit the dust in a particularly nasty car wreck (fun times). I intended the resurrected watch to be a shop watch that would take irregular wear (and absolutely unconscionable abuse), so I went with a non-date version (NH39?) and didn't have to deal with any date complication complications. I also replaced the crystal and dial with aftermarket units. I don't recall any particular challenges related to the movements themselves save a vague recollection that I wasn't entirely comfortable with how tight the fit was getting the movement into the case. I don't have any clue if I used one movement ring or another, and it may not have even been the same watch I'm thinking of. Whatever the case, I went ahead with it, and I'm a famously cautious person with that sort of thing (me and torque specs are a running gag with the car club guys), so it couldn't have been that bad if I'm even remembering correctly.

  • Like 1
Posted (edited)

Cheers for the info Spectre6000. Yeah I'll have a go at it. Cheap and Cheerful way of easing my way into working on Mechanical watches.👍 

Edited by Ruffass
  • 1 month later...
Posted
On 11/22/2024 at 8:45 AM, Ruffass said:

I think if things go wrong I'll just have to try and convert it to the NH36 movement which seems much cheaper.

 

 

I did the nh36 convertion of my Seiko 7005-8042. It was given to me by my dad a long time ago. Parts were hard to source or not available even in the service center here in the Philippines. I removed the grey/black ring and was able to use the original movement holder after grinding it.  I had to replce the stem but used the original crown. The watch dial also had to be replaced since I don't know how to recolor it. I buffed the acrylic starting at 600 grit to 5000 grit sandpaper. After buffing, I used cutting and waxing compound. Acrylic was clead again. So far It's still working and keeping +4 spd. Ok by my standards for a revived seiko watch from the 70's.😁

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Interesting, thanks for the detailed post. I saw one of those Swiss Nano machines a while back in another youtube video from  the Weiss Watch Company.
    • Hello and welcome to the fo4um. Enjoy
    • Welcome to the forum, enjoy.
    • You're asking a pretty broad question and you didn't specify the machine but yes it's simple especially if you have the right machine. The question has problems but I'll take it as it is. Is it really that simple yes especially if you have the right machine. So in the video below he's making a screw and yes it really is that simple but pay attention to the machine it is not simple at all probably wasn't cheap but it is small it will probably fit in your garage. Unfortunately wouldn't fit in my garage as it's far too cluttered up with things. In the video he talks about making a screw and pay attention to the machine. The machine has lots and lots and lots of cutters and lots of things to do lots of machining all-in-one machine conceivably one step after another all programmable. If you look at his channel lots of CNC's stuff and there are several other videos related to this machine. He goes to the factory where they talk about it and show all the other machines they make in Switzerland.  I did look up the specifications the machine I don't recall the price it's not going to cut wheels I think it has a maximum diameter around 11 mm basically it's really good for making small diameter watch parts. Then in one of the other videos he goes to a factory that used to make parts with waterpowered machinery been in business for 100 years and everything they now make is made with CNC machines including this one. What was interesting with the factory photo was that when they make some parts they can put them on a optical comparator comparator compares with whatever the reference is and the machine can be programmed to adjust its cutting to make sure everything is actually being made to specifications. Oh and then somewhere in all of this there was at least one picture of a balance staff can't have a CNC Swiss machine without making balance staffs.   It would be really nice if we had pictures of the machine. Then yes if you look at the page for wheel cutting you can enter parameters and it will generate a G code but he left out things? Notice he has a picture of a complete wheel but the G code isn't making a complete wheel it's only cutting the gear teeth I don't see whereas the program for crossing out the spokes? Typically when you see people cutting gears once the teeth are cut most the time the spokes are cut by hand. Occasionally someone will mill them out but typically not with the program which seems strange if you have CNC capability for instance one of my friends fill it used to design assembly line equipment or things to make things. So his hobby was to continue to make tools to make things like clocks. Very interesting and clever clocks but his true fund was making the machines to make the clocks. Then machine is not controlled by G code like we would typically find today as the stepping motor controller he has was made a long time ago and the individual controllers used a textbased program. So the company had a editor you could write a program to cause each the stepping motors to do something. So basically once you figure out how to cut a gear he would just change the parameters for different size gears so here's an example of a gear as you can see we have the teeth and the spokes. Then we have a picture the machine which sucks because it would've been so much nicer if I could've taken a picture when it was cutting a gears so we can see things better. Then yes there is a worm gear stepping motor indexing this is a mini lathe and the indexing is at the end of the lathe head hiding. The basic operation of this machine would be brass sheet not cut to a specific diameter size not even round mounted on the machine. Then it turns and a milling cutter will cut the diameter. Then the gear would be cut with a gear cutter. The same mill cutter for the diameter although conceivably change the size I don't know but basically the same milling for cutting the outer diameter would be used to cut the spokes. I really can't remember how he did the center hole but whatever it was was very precise.          
    • Yeah I know the site and the creator of it.  the two video clips are good examples of the quicker method and a full tear down.  the quick method will work in many cases. But not always and not for all the different movements.  I strongly suggest to not bend the four tabs as was done in the first clip.  Instead there are three tabs that insert into the top plate, Much saver way as to not break a tab.
×
×
  • Create New...