Sunday, March 3, 2024

A New Custom Dial for My 6155 GS

 The first custom dial that I made for my 6155 rescue project turned out exactly as I had envisioned it but, unfortunately, sometimes things look better in my mind than they do in reality.  The texturing of the background just seemed to be a bit too understated.  In other words: boring.  My favorite Grand Seiko dial has always been the Mt. Iwate, so I decided to try and replicate that look.  I disassembled the first dial so that I could reuse the hour markers, date window and logos that I'd previously made, then got to work on the new dial base.  It was made in exactly the same manner as the previous one,  except for the application of the radial feathering.  The feathering was done with a 90 degree carbide bur, mounted in a Foredom handpiece that was mounted in the lathe's milling attachment.  The milling attachment was set at 45 degrees from horizontal and, starting from the center and using the power cross-feed, the pattern was cut as the dial rotated in the headstock.  I had experimented with a number of scrap pieces in order to find the combination of spindle RPM and cross-feed rate that would achieve the look that I was after.  Once that was done, the slots for the hour markers were machined, the minute markings engraved and the date window aperture were done exactly as done previously.  Prior to plating, I brushed the dial with a slurry of rottenstone, using a short-bristled "stippling" brush, in order to very slightly matte the surface.  This would make the silver plating a bit more white than silver.  After plating, all was reassembled.  I'm much happier with the result.

The finished dial


Sunday, February 4, 2024

Refreshing a Rolex 16753

 A long-time customer brought this 1981-vintage Rolex GMT Master in to be serviced, have the bracelet repinned, repair the scratched crystal and a general exterior clean-up.  As in gunmaking (or any other profession) there are those that probably should not be doing the work that they do, and this particular watch is a good example of why one should be very careful about choosing who they allow "under the hood".

Let's start with the case.  Rolex cases (pre-2003) have their lugs drilled completely through, theoretically making removal of the bracelet or strap pretty much foolproof.  Well, nothing is foolproof for a sufficiently talented fool.  The majority of external damage to the case was due to failed attempts to remove and replace the springbars.  There was also some minor rust pitting (stainless steels aren't rust proof, but rust resistant) but nothing that would compromise sealing of the case.

The case, before:

The case, after (no buffing wheels are employed during the process):

The polycarbonate crystal had a number of deep scratches.  They were block-sanded out prior to hand polishing.

Now, on to the dial and hands, which were mercilessly scratched.  The dial scratches were no doubt caused by careless removal and replacement of the hands.  The scratches on the hour and minute hands appear to have been caused by attempting to scrape them clean with an X-acto blade or something similar.  Beyond properly cleaning the dial, not much can be readily done about it, but the hands can be saved.

Before:

The dial and hands, after:

Now, on to the movement.

The autowinding rotor was rubbing on the balance cock AND the inside of the caseback.  How can this be, you wonder?  Because the rotor axle was not properly secured, allowing it to "float" in and out and wobble while doing so.  

The retaining ring for the rotor is itself retained by the rotor pinion.  This pinion has a pocket machined into one end that envelops the retaining ring, preventing the ring from backing out of its slot in the rotor axle.  

The problem here is that the rotor pinion was installed upside down, thus negating its ability to retain the ring that retains the rotor.

As with their counterparts in the gun world, the uncaring are duty-bound to wreck every screw slot that they encounter, and sometimes even the area around the screw head.


After disassembling the autowinder, I flipped the movement to disassemble the date, dial train and keyless mechanisms...
 
Where I found this "MacGyver" repair.  As my friend D'Arcy says: "Some peoples' kids..."

Then the movement was flipped back over to disassemble the balance and main train.

Everything cleaned, subassemblies assembled and lubed and ready for final assembly and lube.

After reassembling/lubing the movement, the dial and hands are reinstalled (making certain that the date changes at midnight) and the movement is recased (the crystal and its retaining ring having already being reinstalled).  At this point, new stem and crown seals are installed, as well as a new caseback seal.  Prior to final tightening of the caseback, the watch is tested on the timegrapher.  After final adjustment, the caseback is sealed up and the watch is wet pressure tested to 3 atmospheres (a.k.a. 3 BAR or 30 meters).  After the wet test, the timing is again checked and then the GMT bezel is assembled.  This is done so that there is no chance of water being trapped inside the bezel.


 
 
With the watch itself finished, I turn my attention to the extremely worn "Jubilee" style bracelet.  The tools used in disassembly and reassembly are of my own design and manufacture.  They are not the "fecalium" alloy crap that sells for way too much money from the supply houses.  They are similar in function but made of much better material and are much more precise.

The lower endpiece had a couple of dents in it which I remedied at this time.  I made a backup block (shaped to fit the inside of the endpiece) and used that to support it while I tapped the dent out.  Then the brushed finish was reapplied.

The bracelet was reassembled with new pins.  The worn link screws (for the removable links) were shop-made from 316 stainless.

I reinstalled the bracelet (after taping the lugs) and the job is done.  Even though it still sports the damaged dial and bezel insert, it is now much more presentable.  Most importantly though, it functions correctly.