One of my longest-lived watches is a grab ‘n’ go beater, a bastardised aggregation of disconnected parts that came together over 10 years ago to yield a pretty coherent watch.  In fact, I’ll go so far as to say that it’s a beautiful thing, exuding the kind of delicious soft patina that engenders warm glows of satisfaction. 

The various components derived from an assortment of mismatched junkers whose confused identities included affiliations with four different Seiko models: 6309-8019; 6309-7150; 7009-8590 (maybe); and 6319-8000.

The standout component was the dial, a starburst dark brown with gold highlights and applied, lume-filled markers reminiscent of the style used in Seiko 150m and 300m diver’s watches of the late ‘60s and early ‘70s. 

The 6309-8019 case that belonged to the dial was tatty, with parts of its gold-plating worn down to the brass substrate beneath and to my mind, unrecylcable.

My plan at the time was to find a suitable steel case to pair with the lovely dial and handset and my subsequent search yielded a mis-identified 6309-7150 whose case in fact belonged to a 6319-8000.  Without, rehearsing any more of the details of that particular project (you can read about it here), the end result was watch that will form the starting point of a rethink and a repackaging, combined with some titivation to the engine room.  We begin this episode therefore with my trusty but slightly scuffed faux milspec Seiko 6309.

One of the features of this watch that I like so much is the soft domed acrylic crystal.

The 6309A movement displays a degree of tarnish that betrays the decade that has passed since it last was serviced.

That passage of time is revealed also in the slightly diminished amplitude on a full wind, although in other respects the movement is performing well and functionally, everything works correctly.

Here’s the dial-side of the movement, with the date disk and dial removed.

Most of the gear train is jewelled on this side, apart from the barrel arbor hole, but the same cannot be said of the train side.

Notably, the third and fourth wheels are each served by steel bearings.  If you subtract the two jewels that serve the autowinding mechanism, this is basically a 15 jewel movement.

One of the peculiarities of the 6309 (and 6306, 6319) gear train is the circular holes in the train wheels.  Initially, I thought this might have been a design choice dictated by the interests of cost-cutting/ease of manufacture but as we’ll see later, there is some logic to this rather industrial design choice.

My plan for this movement is to up-jewel it but rather than actually upjeweling the original 6309, I intend to replace the main plate and train bridge with parts from a 6319, together with replacement escape and third wheels, both of which dedicated to the 6319.

With that in mind, the 6319 parts join the dismantled 6309A to percolate in the watch cleaning machine.  With that done, and the parts nicely dry, the assembly begins with the installation of the mainspring into the barrel.

I have used Kluber P125 on the barrel wall and a touch of 8200 for the mainspring and barrel floor. 

In place of the single jewel serving the escape wheel, and steel bearings serving the third and fourth wheels in the 6309, the 6319 barrel and train bridge boasts a pair of Diafix settings for the third and escape wheels and a jewel for the fourth wheel.  One jewel becomes five and overall 17 will become 21.

The movement comes together in the usual order, starting with the setting parts, followed by the centre wheel and its bridge and then the gear train, click and barrel and train bridge.

The 6319 main plate is curiously devoid of any decoration, having a flat matt, bead-blasted appearance.  Note that the holey gear wheel design includes the centre wheel.  Four holes for the fourth wheel, three holes for the third wheel and two holes for the centre wheel.

The two Diashock settings provide the supports for the upper and lower pivots of the balance staff.  Their oiling and cleanliness is critical to the smooth operation of the movement.

The only part of the reassembly process for this movement that can be a bit of a fiddle is the installation of the setting wheel lever. 

One aspect of the assembly that you won’t necessarily appreciate the first time you work on a 6309 is that the quickset will not function properly until the day jumper guard is installed because it prevents the setting wheel lever from jumping out of position when operated.

In the photo above, you may be able to see where the date jumper guard makes contact with the post sticking out of the setting wheel lever assembly, holding it in position.  It’s time to see how the movement is running and to perform a preliminary regulation, assuming all looks well.

These movements are known for their relatively low amplitudes and so 236 degrees out of the box with its original mainspring is more than satisfactory.  The negligible beat error and consistency in numbers dial down (+13 s/d, 231 degrees, 0.1 ms beat error) lends confidence that all it needs is a slight tweak to the timing once it’s had time to bed in.

I was a little uncertain about whether to install a 6319 autowinding bridge assembly or stick with the original 6309 part.  The movement that I’ve ended up rebuilding is essentially a 6319A but many of the ancillary parts are from the 6309A.  In the interests of keeping faith with the marking on the dial and case back (more of which shortly), I ended up opting for the original 6309 part.

Refitting the day wheel, dial and hands brings the movement reconstruction to its conclusion.

Now we come to the question of the case.  The previous 6319-8000 case has a great deal of appeal in its balanced dimensions and Grand Seiko Self Dater-esque lugs.  There is also something to be enjoyed in the softening of its lines that has come from the refinishing that was required to eliminate its original battle scars.  However, it is my intention to return this watch more closely to its original identity, notwithstanding the modifications to the movement, and so I set about looking for a steel equivalent of the gold plated original 6309-8019 case.  By a stroke of luck, I happened upon a new old stock example of a 6309-8010 case for sale from an eBay seller in Thailand and nabbed it.

The new case is on the left in the photo above, and the out-going case on the right.  To be honest, I think I prefer the thicker lugs of the 6319 case but am going to stick to the plan as conceived, barring one slight adjustment to the new case.  The correct crystal for the 6309-8010 is the 310T18ANS but this has a flat top with an angled bevel that I think lends a certain sterility to the case.

Instead, I opted for a Sternkreuz 310T10ANS whose tension ring has the same dimensions as the one fitted to the original 310T18ANS and therefore which fits perfectly, but which has a soft-domed profile more to my liking.

The slightly smaller case requires the stem to be trimmed slightly, in fact to the fullest extent allowed by the design of the crown.

With the crystal replaced and the stem sized, we are ready to fit the movement to the case, topped off with the winding weight.

Before the big reveal, we need to select a strap.  I gave it a run around the block with a 19mm rubber tropic fitted, but in the end chose a vintage-style stitched black leather strap.

I think this strikes the right pose for a watch whose dimensions are closer to dress watch but whose outward appearance nods emphatically in the direction of ‘pseudo-milspec’.  The soft dome profile provides a further enhancement to that personality.

The end result is one that leaves me in two minds.  I can’t help but mourn a little for the change in personality of this ‘old faithful’ of mine:  I think it has lost a little of its masculine character in acquiring its slimmer, more refined body.  But setting those reservations aside, the end result is really rather special.

The gilt dial and steel case is an irresistible combination and with its movement having been given a new lease of life, I see this one maintaining its previous role as a do-it-all watch for all seasons and all occasions.