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Forum Home > Parts Info, Tech Tips and Tinkering > Sticky: The all-too-common Displaced Finger Tension Spring chrono' sweep hand problem

Seiko7A38
Site Owner
Posts: 9312

I was sorely tempted to write some sarcastic comment in response to this recent thread on the UK RLT watch forum:


http://www.thewatchforum.co.uk/index.php?showtopic=73593 (entitled: Seiko 7A38 Beat Up Crystal)




I mean just how many times did I write about displaced 7A chrono' centre second finger tension springs, on RLT in the last 3 years ? 


Mike 'Tixntox' wrote in reply to the OP:

I think that the spring clip in the centre right of the watch (currently over the 'nad' in the word unadjusted) is skewed around under the screw (the right hand screw of the three on the centre plate). The end of the extended portion of the clip should be over the purple jewel in the centre of the movement ....

Somebody give the man a from me !

Meanwhile, I really must learn to bite my tongue. 

February 23, 2012 at 4:42 PM Flag Quote & Reply

7ARCool
Member
Posts: 168

To be honest I do not understand how the "Centre seconds finger tension spring" works.

A simple explanation would be nice Paul.

If the guy with the beat up crystal thinks that crystal is bad, I have a 7A38 with a crystal that looks like it has been used as a welders bench for twenty years,with metal fragments melted into it ! :lol:

February 23, 2012 at 9:07 PM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

It simply acts as a damper to smooth the movement of the chrono' sweep second hand, Chris.

It should bear very lightly on the end of the axle protuding through the jewel in the middle of the Chrono' Centre Seconds bridge.

If it is removed altogether, 9 times out 10, the chrono' sweep hand will still work - as appeared to be the case with that one on RLT.

What is more common, particularly during battery changes, is for clumsy jewelers to accidentally displace the finger spring to one side of the axle, so that it rubs on the side of the shaft and acts as a brake. Then the chrono' sweep hand will be very reluctant to move.


Here's one of the first times I encountered it, in April 2010, on my 7A38-726A. Excuse the strap. I was going through a Lizard phase:



The photos above were originally posted in this thread on RLT: http://www.thewatchforum.co.uk/index.php?showtopic=53474 entitled:

A Rant About High Street Watch-Botchers A common problem with Seiko 7A38's - easily fixed !

February 24, 2012 at 3:49 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

Topic re-named and thread moved to 'The Workshop / Tinkering' section, as it has become more of a 'Tech Tip'. ;)

February 24, 2012 at 4:12 AM Flag Quote & Reply

JSS
Member
Posts: 32

"I mean just how many times did I write about displaced 7A chrono' centre second finger tension springs, on RLT in the last 3 years?"


.....LOTS

Even I remembered your posts about that.  I was going to post and tell the guy about the spring but I thought it was TOO obvious.

Just goes to show, even a little knowledge can be helpful.

 

February 24, 2012 at 7:21 PM Flag Quote & Reply

7ARCool
Member
Posts: 168

Cheers Paul for explanation on the tension spring. :D

February 25, 2012 at 1:19 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

I hadn't seen one in a while now, personally - but then I came across this classic example in a German eBay listing earlier this week:

http://www.ebay.de/itm/290797343746




It's a rather grubby two-tone 7A38-7280 which could use some TLC. Note also the incorrect orientation of Tachymeter dial ring spacer.




Looks like the seller really splashed out in the battery department, too. :roll:




From the seller's description: Bei mir dreht sich nur der Zeiger bei 3 Uhr nachdem man die Batterie einsetzt und auf den Knopf drückt.

Which roughly translates as: For me only the pointer at 3 o'clock turns after inserting the battery and pressing the button.

Not exactly a surprise, with the 'brake' firmly applied to the centre seconds sweep hand. :lol:


October 28, 2012 at 7:09 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

It's been a while since I'd inadvertently bought a 7A38 with this problem.

But earlier this week I encountered it once again on my newest incoming NOS Racer J39723-70, which apart from needing the battery replacing, demonstrated all the classic symptoms. It had almost certainly been left like this since the last battery change, years ago. :roll:



If you look closely, you can see that the finger tension spring has a dimpled impression in the middle, where the clumsy jeweller must have squeezed it down pretty hard on the centre seconds shaft, before subsequently deflecting it to one side. I later replaced it. ;)

And you wonder why I have this loathing for high street watch botchers ? :mad:


August 24, 2013 at 8:38 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

Here's a classic example of a 7A38 with the displaced centre seconds finger tension spring problem listed today by a UK eBay seller:


http://www.ebay.co.uk/itm/331044658813

VINTAGE GENTS SEIKO 7A38-7289 CHRONOGRAPH DAY DATE QUARTZ WRIST WATCH HEAD ONLY

 

Seller's comments read: "ticks, but hour and minute hands are not functioning"


Two of the seller's (9 in total) listing photos:




Description reads:


Gents Seiko chronograph wrist watch head, it will tick but for some reason the hour & minute hands are stagnant, able to move them with the crown, day date changes smoothly, no strap is fitted, there are several marks on the glass and may need to be replaced, please bare in mind, this watch is not fully functional, and repairs may be expensive, it is listed for parts only, and will not accept returns, partial refunds etc, so bid accordingly.


Now, think about this. In an earlier post, I wrote: 

Not exactly a surprise, with the 'brake' firmly applied to the centre seconds sweep hand. :lol:

So we know that the chrono' sweep second hand wouldn't work (no mention of chronograph functions in the seller's description).

But if there was also possibly wear in the central hand stack or main base-plate centre jewel ....

Could this displaced finger spring be enough to bring the main hands to a standstill - say by causing the cannon pinion to slip ? :/


October 14, 2013 at 6:54 PM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

Another classic example in this 'Spares or Repair' stainless 7A38-7190 with discoloured sub-dials, listed on eBay earlier this evening:


http://www.ebay.co.uk/itm/111251451672



Before the seller revises it again, note the part of his description I've outlined in red:



Currently his 5th listing photo, which I suspect may be hastily removed - in due course, when he reads this. :P



Zoomed:




Yeh - and the 'gold tone' sub-dials on a white 710L dial are really meant to be that colour - right ? 


January 5, 2014 at 4:44 PM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

Another 'classic' spotted on eBay, listed by a UK seller this afternoon. :roll:


http://www.ebay.co.uk/itm/360864924550


Description

 

SEIKO 7A38-7020 Quartz Chronograph Steel Gents Watch Runs- Needs Attention

 

31mm Grey Dial with White and Luminous Hands 3 Sub-Dials and Date Display

36mm Stainless Steel Case and Back

No Strap

Seiko 7A38 Quartz Chronograph Movement

 

In Used Condition - Movement Runs and Keeps Time but the main second hand judders but doesnt move

Movement Working - Runs but Sweep Second Faulty




A penny for your thoughts ? :lol: My first one was .... 


February 22, 2014 at 10:07 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

All the examples cited so far in this thread have been 7A38's (plus the odd Orient J39), but this 'inflicted problem' can afflict any 7Axx.

Spotted this 7A48-7009 'Parts Watch' listed by a US eBay seller: http://www.ebay.com/itm/301212704769




Mens Seiko sports 100 chronograph moonphase watch model # 7a48-7009.

For parts or repair. Watch works great but chronograph doesn't work. Selling as is.


The seller's third photo of the movement isn't the sharpest, and there may be other issues, besides ....




But it's not difficult to spot why the chronograph centre seconds hand wouldn't be working. :roll:


June 16, 2014 at 4:48 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

Seen it on a few 7A28's too recently. :roll:

This (mis-titled) listing for a 7A28-7049, fitted with an non-original replacement bracelet, which appeared overnight made me chuckle.


http://www.ebay.co.uk/itm/121384571894


THERE IS NOT A FULLY FUNCTIONAL SEIKO WORKING MOVEMENT INSIDE THIS CASE. "IT DOES NOT RUN PROPERLY," I RECEIVED THIS WATCH AS PARTIAL PAYMENT ON A PURCHASE... THE CHRONOGRAPH DIAL FUNCTION SEEMS TO WORK (NOT SURE), BUT THE TIME FUNCTION WITH SECOND HAND IS NOT MOVING... NO GUARANTY SELLING AS IS......

SELLING FOR PARTS OR REPAIR ONLY... NO RETURNS!!


If you're wondering about the slightly odd description, it's because the US eBay seller gmc-jr is more used to dealing with salesman's sample cases. In fact, he's knocked out half a dozen 7A38 sample cases in the last month or so. He's obviously used / re-edited one of those previous listings as a template, hence the first sentence. :roll: But looking at the state of the finger tension spring in his photos ....




Perhaps he should stick to selling salesman's sample cases ! :lol:


July 13, 2014 at 3:50 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

There was one other small issue with my recently acquired 'cheapie' ex-eBay Germany stainless 7A38-7270 that I hadn't mentioned.

A somewhat recalitrant sweep second hand. :/ Guess what the cause was ? :roll:


January 20, 2015 at 9:34 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

The gross incompetence, ignorance and laziness of some eBay sellers dealing specifically in watches never ceases to amaze me. :roll:

Take this dog-eared stainless 7A38-7190 with badly stained sub-dials, fitted with a non-original replacement bracelet, listed yesterday by UK eBay seller yeti.watches - whose less-than-stellar offerings have previously featured in threads in the eBay section.

The reason I'm tacking it onto this thread will soon become apparent.


http://www.ebay.co.uk/itm/351326866650

Now check out the seller's two photos of the movement (you may need to zoom in on them) ....




That easy fix apart, I still wouldn't touch it with a barge pole ! 


February 27, 2015 at 6:04 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

There are some downright incompetent cowboys on eBay lately. :roll: A little over half an hour ago, a UK ebay seller vw_tornado listed a stunning well-used stainless 7A38-7060, fitted with a non-original replacement bracelet and a seriously mis-aligned Tachymeter ring, asking £150 as a Buy-it-Now.


www.ebay.co.uk/itm/STUNNING-SEIKO-QUARTZ-CHRONOGRAPH-7A38-7060-SILVER-FACE-RETRO-DAY-DATE-/131475729783


His description starts off:


This is a seriously handsome example of this classic timepiece. I wore it for the day to make sure it all works okay and had several comments from colleagues as it stands out so much.

 

I fitted a new battery yesterday and all of the functions seem to work okay.


Oh really ?  Bet they don't all work okay anymore - thanks to his clumsiness. Check out his last couple of photos ....



Incredible that he posted this zoom of his own cock-up. 


April 2, 2015 at 5:09 PM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 9312

It's been a couple of years since I last updated this thread. It's not that I haven't seen (more than) a few instances of this self-inflicted fault in the intervening period - I just hadn't seen any I deemed worthy of comment. ;) That was until this morning, when I saw this average worn condition 7A38-702A listed yesterday evening by a UK eBay seller dazzler3369. He seems to be under the illusion that it's near mint. I suggest you examine the photos for yourselves. I've already formed my own opinion. But that wasn't the reason I'm mentioning it. It's his claim that it's in FULL WORKING ORDER.


http://www.ebay.co.uk/itm/401372053950


I really don't see how !  


Yet another classic example of this basic cock-up - in high resolution.  


July 25, 2017 at 4:57 AM Flag Quote & Reply

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