Seiko 7A38 - by the numbers

It's not as if I needed another stainless 7A38-7020 (or 7A38-7029). I'm very fortunate that my collection already includes half a dozen decent examples, varying in condition from NOS / Mint (a couple were refurbished using salesman's sample cases and NOS bracelets) to better than average. Top Row: 7A38-7029 SAA013J's; Bottom Row: 7A38-7020 SAA009J's.


Besides those six I have another restored beater and a couple of modded Frankens, based on the 7A38-702x watch case. Thankfully, I bought the majority of them long before the 'Royal Oak' misnomer hype escalated and so paid considerably less for them than the ridiculous prices that speculators ask nowadays. But I never could resist the occasional 'bargain'.

Readers may recall a mildly humorous thread in the Workshop section of the old forum that I started nearly three years ago, but then temporarily locked (with the intention of continuing it later), but subsequently left unfinished.

7A38-7020 Basket Case restoration - a.k.a.The RUSTO-mod.


Here's a couple more 'as received' photos I posted in that abandoned fledgling topic:


Famous last words, I ended my second post with: To be continued ....

In fact, I'd started to strip the watch down, not long after I received it and in the first two weeks of August 2018 had taken literally dozens of photos. First thing I'd none was to remove the p/n B1171S bracelet and in my habitual manner, left it to soak overnight in neat Flash cleaning fluid. That certainly loosened up a few years worth of encrusted crud.

Here's a few more, which should be graphically self-explanatory and give you some idea of the horrors I found inside.

At that early stage, I already had absolutely no illusions of being able to rescue the rusted-out movement, but decided to make a concerted effort to save the dial and hands. I gingerly rotated the hour and minute hands to align them with the sweep second hand (which was seized solid and wouldn't budge), to facilitate their pulling in one operation.


I was relieved that the hour and minute hands came off cleanly and the latter will only require a little polishing of its boss to remove the rust staining. Whereas I've managed to source NOS hands in years gone by, Seiko p/n's 12BH0KNH and 12BH0KNM (which were also used on the 7A28-7040/9) pretty much fall into the 'unobtanium' category nowadays.

My efforts at saving the sub-dial hands were rather less successful. Those white deposits on the sub-dials are where the aluminium hands had been presumably sat in a tiny pool of water and dissolved. My first clumsy attempt at moving one.

Strike 2 !
The fact that I actually managed to remove one sub-dial hand intact is something of a fluke and completely academic. In its badly weakened state, I strongly suspect it would break, were I to try and re-fit it. Luckily, I discovered I still had a secondhand used set of p/n 04E14AW in my spare hands stock and wrote myself a Post-it note reminder to that effect.


Having successfully removed the hands, I was annoyed (with myself) to notice that, despite 'using protection', somehow I'd managed to mark the dial - there's a tiny spot of paint missing between the 1/10s and constant seconds sub-dials.


Academic really, when you consider the overall condition of the dial, but bloody annoying nevertheless. I plied the rusty dial screw @ '35' with WD-40 and after some gentle persuasion, to my surprise, it came out without the need to resort to drilling or grinding. The receding water marks on the underneath of the dial plate tell their own sad story.


Despite having marked the dial, I resolved to attempt to clean it up, best I could, with a view to re-using it. Here's how it looked after a couple of hours work, carefully dabbing away at it with tiny pieces of moistened damp sponge and the obligatory Rodico. Better ?

Seiko7A38 wrote: ↑Mon Jun 28, 2021 9:49 amAt that early stage, I already had absolutely no illusions about rescuing the rusted-out movement ....

As I'd expected, the badly rusted movement was another story altogether. The Top side looked deceptively reasonable:


Starting from the backplate, after giving each of the 7 retaining screws a tiny drop of WD-40 ....


.... and using a freshly sharpened screwdriver, I was pleasantly relieved that they all unscrewed:


To my greater surprise, the PCB actually peeled off in one piece, but needless to say, is completely buggered.


Whereas there are a few parts that could possibly be re-used, the real surprise bonus was the switch lever at 10 o'clock was almost rust free and pristine (compared to the other two) - and still springy !!

Perhaps I was a little hasty leaving that feedback !

And that is where I left it, nearly three years ago. I didn't bother to dismantle the movement any further and carefully put the disassembled components into ziplock poly bags and small plastic boxes (I use empty DDS / DAT tape cartridge boxes) and thence into the obligatory takeaway container and added it to my growing stack of 'round-tuit' projects.

Whereas I wanted to restore it, keeping as much of the original watch as possible, I didn't see the point of expending hours of effort cleaning up any possibly salvageable movement components. The simplest solution might have been to fit a NOS (or known working) replacement movement. Problem was, ever the stickler, I wanted to keep it 'original'.

The US export market 7A38-7029 SAA013J comes fitted as standard with an English / Spanish day wheel. The European export 7A38-7020 SAA009J mostly have English / French or English / German. This particular 7A38-7020 had come from the States and thus had an English / Spanish day wheel. Unfortunately, as can be seen in the first two photos of my previous post, it had succumbed to corrosion, particularly around the DOM / SUN area. I guess what really stalled my restoration at the time was that I really didn't want to 'waste' a NOS replacement movement in it - and the fact that although I had a couple of used day star wheels in my dismantled movements box, I didn't have an English / Spanish.

But I did have a Seiko 7A38A movement, fitted with an English / Spanish day wheel sat somewhere one didn't belong - inside my Racer J39930-70 'wrong un', which for 5 years had festered, fitted with not only the wrong movement, but also the wrong case-back. In March of this year, I finally found the solution to both issues in another donor J39930-70, which I wrote up in this thread in the non-Seiko re-branded section: Orient J39930-70 - (Correct) Closure at last !!

Those of you who've read it may have noticed these couple of paragraphs:

Seiko7A38 wrote: ↑Thu Mar 18, 2021 7:50 amSo I've just sent them both off to Simon 'Sir Alan' Wilkinson to have their movements serviced, with explicit instructions of which set of parts to use to rebuild the 'NOS' J39930-70. The donor will not be resurrected as such. The surplus Seiko 7A38 movement is already earmarked for another unfinished project.

This partial quote is from another related thread in the Workshop section. Simon 'Sir Alan's services of my 7A38's

Seiko7A38 wrote: ↑Sat Jun 19, 2021 3:26 pmOnce he'd serviced it, following my instructions, Simon fitted the Orient J3920 movement where it rightfully belonged - in the almost mint J39930-70. When he later serviced the Seiko 7A38 movement, he dropped it back into the 'donor' case, without re-fitting the hands (for transit protection). Reason being I have other plans for it. Of more anon.

So if you haven't already guessed from my clues, that Seiko 7A38 movement, recently serviced by Simon, which happens to have the desired 'correct' English / Spanish day wheel, is destined to find a new home in the 7A38-7020 'Rusto-Mod'.

At the moment, my only other quandary about the 'originality' of the 'Rusto-Mod' concerns its aesthetic appearance.
If I'm going to fit the original (cleaned up) 703L dial, the watch is going to be 'cosmetically challenged'. Whereas I've had plenty of practice at re-finishing 7A38-702x bezels, cases and bracelets and am quite capable of doing another, without wanting to appear lazy, wouldn't it be more in keeping if I left it the way it was, replete with dings and scratches ?


I was even considering retaining the original slightly fogged crystal. Yesterday I stripped and cleaned the watch case and pushers (photos to follow) and got a bit of a shock. Notice that yellowish residue under the rim of the crystal ? Without examining it closer, I'd incorrectly assumed it was rust staining. It wasn't. It's glue ! I pressed the crystal out to find that not only was it only 0.9mm thick, but plastic - not glass !! So that now definitely won't be getting re-used !

Seiko7A38 wrote: ↑Mon Jun 28, 2021 8:04 amFamous last words, I ended my second post with: To be continued ....

Of more anon (tomorrow is another day and all that). To be continued .... Honestly.

Seiko7A38 wrote: ↑Mon Jun 28, 2021 5:08 pmYesterday I stripped and cleaned the watch case and pushers (photos to follow) ....
Of more anon (tomorrow is another day and all that). To be continued .... Honestly.

Apologies, due to other distractions, the project's fallen a little behind schedule. Here's the first couple of photos:


I'm not sure why, but sometimes the pusher assemblies used in the stainless 7A38-7020 SAA009J and 7A38-7029 SAA013J (Seiko p/n 80600709) come fitted with those little stainless retaining washers, but other times they're omitted. The Rusto-Mod's pushers didn't have them. Seeing as I was stripping and rebuilding them, I added them. As usual nowadays, when refurbishing SPORTS 100 rated 7A38 models, I've used Cousins' cheap generic mini O-Ring seals, p/n G39083 which they describe as a substitute for Seiko p/n EC0060B01, costing a mere £1.50 for a pack of 10, rather than say genuine Seiko p/n EC0060B0A @ £4.35 a pop ! Apart from making economic sense, my watches never get wet anyway !


At this stage, with the components cleaned and dismantled, it might have been an opportunity and a relatively simple matter, to skim and re-brush the case and bezel. For the moment, I've deliberately elected not to refinish them, so that the rebuilt watch will retain some of it's 'well-loved' character and match the rather 'less than perfect' cleaned up dial.


Here's the re-assembled case, now fitted with a new Sternkreuz p/n MSM310 crystal, but complete with battle scars.

Another belated update on my progress last weekend ....

The donor Racer J39930-70 yielded up its Seiko 7A38 movement, which had been capably serviced by Simon last month.

Seiko7A38 wrote: ↑Mon Jun 28, 2021 9:49 amI was relieved that the hour and minute hands came off cleanly and the latter will only require a little polishing of its boss to remove the rust staining.

It took no more than a couple of careful dabs with Silvo Duraglit followed by very gentle wiping with a microfibre cloth to remove the surface rust. I was quite pleased with the result, which left some tell-tale pitting around the boss.

Seiko7A38 wrote: ↑Mon Jun 28, 2021 9:49 amLuckily, I discovered I still had a secondhand used set of p/n 04E14AW in my spare hands stock and wrote myself a Post-it note reminder to that effect.

Sometimes I amaze myself at how well organized I can be (shades of O.C.D.).


One of those sub-dial hands was obviously NOS, but it took me a while to remember where the other 3 had come from. They had slightly tarnished bosses. IIRC, they were probably from another stainless 7A38-7020, which I bought off eBay Germany back in 2011. It was a non-runner that had suffered a fairly catastrophic battery leak.


Initially, I broke it up for parts; ironic as in some respects, it was in better condition than the 'Rusto-mod'. The acid damaged dial donated its black sub-dial plate, to form the basis of my two-tone 7A38-7020 'split-dial' Franken, which uses gold sub-dial hands. I later re-built it using another working movement and the dial and hands from a 7A38-7029 salesman's sample case, hence how I ended up with a surplus set of used p/n 04E14AW sub-dial hands. But I digress ....

More text ....


More text ....

Here's a slightly different wrist shot to the one I just posted in the WRUW thread ....


.... compared to a similarly cropped 1:1 format version of my original 'as received' photo from nearly 3 years ago: