Best birthday present: an ETA6497 SKULL Watch !

[MarkK]

Birthday priority...

I am currently working through level 3 of the watch repair course. I had planned to start my practical training on level 2;  stripping down, oiling and rebuilding a Seagull 6497.

However, my daughter Lisa has her birthday coming up on April 10th. And in early March I decided to build a real Swiss watch as a present for her 23rd birthday!  Although this is not about watch repair, this activity already proves a nice exercise for me to practice using various tools. 

The watch is already 95% finished. Now I am waiting for 2 little case clamps before I can proceed and finish. 

Below I show you what I did up to now!

Lisa likes wierd and alternative things like skeletons and other black stuff therefore I have a good idea of what she likes.   And I want shopping and got all these parts, including a NOS ETA 6497:

[MarkK]

I found a brand new but old Swiss ETA 6497 in Greece. All other parts came from China.
The watch case is stainless steel and is part brushed and part polished. Mineral glass front + back side.  The "Skull' skeleton dial is super cool and the markers, numerals and hands are glow-in-the-dark!

After fixing the watch dial onto the movement the most difficult part is fixing the watch hands. The most difficult is the very small seconds hand...

The little seconds hand flew away 2x from my tweezers, so I had to crawl on my knees and pray to find it back somewhere on the floor. This was quite stressful.

[MarkK]

I used a press to fit the hands. Nevertheless it did not prove to guarantee a flush / parallel mount of the hands. I verified this using a 10X loupe and had to manually adjust the minute and seconds hand. I made sure that the hands are parallel to each other and the dial all around the clock. Esp. the seconds hand has a very small clearance to the dial. It got stuck during testing and I had to correct the situation.

 

[MarkK]

So, in these pictures I show the ETA6497 in the movement holder, here I took a look at where the case screws should go.

And I had a look at the case clamps which I got with the Seagull clone. Unfortunately, I dicovered these are too short to fix the movement inside the 45mm case...So I had to go shopping once again for case clamps.

 

[MarkK]

I test fitted the movement in the case. Because the case has a large diameter, a brass filler ring is supplied and is inserted between the movement and case.

I am quite surprised that even with the brass filler ring there is quite some movement. I had expected a much tighter fit.  This leaves me a bit concerned whether I need to take some measure to do something about the play between movement, ring and case?

Anyway, at this point I discovered that I need to get longer case clamps to fix the movement inside the case. 

I also show a photo of the blue press I used. I am disappointed in the performance and its quality; I hadn't realised that the tips a made of rusty steel instead of nylon. Maybe I should chuck it out for something better with nylon tips.

 

[MarkK]

So, while I am waiting for the new case clamps to come. Let's test and adjust the timing on the Weishi. Before regulation the beat error was okay but dial-up it was running quite fast. I adjusted the watch for now to about +8sec/day. I will repeat the regulation after final assembly.  

Next steps:

a) fix the movement using case clamps & screws;

b) shorten the winding stem;

c) regulate the movement (again);

d) fix the wristband to the watch;

e) test-run the watch for a few days to verify that its running fine!

 

- to be continued -

 

[FLwatchguy73]

Awesome watch. I built 2 similar ones based on the 6498 movement. One has a legit Swiss movement, the other has a Chinese one.

[MarkK]

8 hours ago, FLwatchguy73 said:

Awesome watch. I built 2 similar ones based on the 6498 movement. One has a legit Swiss movement, the other has a Chinese one.

Hi FLwatchguy73,

Same here. I have 2 Seagull 6497/6498 movements waiting for exercising stripdown, oiling and rebuild. I will do this while repeating course level 2.

After that I will make watches out of them for more birthday presents.

I also have a Swiss Unitas 6498 on hand,  I am keeping it to make a B-type pilot's watch for myself.  Here's the watch dial: 

Edited April 1, 2020 by MarkK

[FLwatchguy73]

My first is a Panerai homage. All Chinese parts and I love it.

The next is completely custom Frankenstein. Swiss movement, American dial, Chinese case and a Russian strap. The sub second hole had to be elongated because a 12s Elgin pocketwatch second hand does not quite line up with the 6498 second.

[MarkK]

On 4/1/2020 at 11:16 PM, FLwatchguy73 said:

My first is a Panerai homage. All Chinese parts and I love it.

The next is completely custom Frankenstein. Swiss movement, American dial, Chinese case and a Russian strap. The sub second hole had to be elongated because a 12s Elgin pocketwatch second hand does not quite line up with the 6498 second.

thanks for sharing - thumbs up - I like !!

[MarkK]

So, tomorrow it's my daughter's birthday.... 

Did I manage to finish the SKULL watch with the ETA 6497?! 

YES, but it wasn't easy, there were some hurdles   

• missing case clamps. - I ordered them seperately but in the end, I made them myself to be on time;
• case clamps failing to keep the movement in place.  - That took a lot of time tinkering;
• the winding stem that broke in two while grinding it  - Luckily, I could borrow one from another movement;
• the brass filler ring with poor tolerance, leaving too much space for movement within the case. - Which i solved with adhesive aluminum tape.

see final photos below.  

A watch with a real Swiss movement for my daughter... 

 

 

 

[jdm]

On 4/1/2020 at 1:04 AM, MarkK said:

I used a press to fit the hands. Nevertheless it did not prove to guarantee a flush / parallel mount of the hands. I verified this using a 10X loupe and had to manually adjust the minute and seconds hand.

It is not using a press that installs hands well parallel, it's the hand of the repairer.

First, check that hands are straight on a jeweller cube. Place the collet in on of its holes. If needed straighten gently with a soft tip. 

Then, to make hours and minutes parallel, install the hand with a properly sized (hand held) stake with nylon tips. Check and if one side is too low, incline the stake the opposite side and press gently.

That won't work for the seconds hand, if  doesn't sit parallel I recommend not to try to correct it while is mounted, but remove and work on it on the anvil as above. 

You certainly did a good work, and have learned some of the real issues when assembling a watch from parts that are not designed as an an ensemble, or aren't very precise. 

Compare your results to the ones of the dreamers that occasionally show up here with fantasious ideas but have never held a screwdriver smaller than 3mm, and are normally never seen again. 

Edited April 9, 2020 by jdm

[MarkK]

@jdm thank you for your kind tips!

Despite the the information received in the WR courses, I'd like to ask the following question:

We know that case clamps are meant to fix the movement inside the watch case. Fine. But, how is this mechanically achieved? 

Is it because the clamps simply press against the casing by tightening the screw? Or is this achieved by the watch back pressing the clamps down and creating outward pressure against the casing? 

Without the case back on, I had a tough time to immobilise the movement in the case. Maybe this also has to do with the makeshift clamps made from a tin lid. Unlike a spring, this type of metal bends but doesn't want to flex back. 

Another learning point: make a full bill-of-materials.

Finding brass dial washers and case clamps, is difficult, let alone finding them in the correct size...I still need to find a good supplier for those items...Any suggestions besides eBay and Ali?

Cheers, Mark

 

[MarkK]

Final measurement results on the Weishi 1900 for the Skull watch / ETA 6497-1:

• Beat error in dial up/down positions: 0.0 mS  (but off on other positions)

Rates:

• dial up                      : +12 sec/day
• dial down                 :  +6
• crown @3 o'clock   :  -2
• crown @12 o'clock :  -15
• crown @6 o'clock    : -4 
• crown @9 o'clock    : -14

Let's see in practice whether this regulation gives a good avarage result for keeping time...

Also an interesting experience to regulate a movement. It's quite tricky to do: the slightest adjustment leads to big changes. Demands lots of patience!

Edited April 9, 2020 by MarkK

[jdm]

10 hours ago, MarkK said:

We know that case clamps are meant to fix the movement inside the watch case. Fine. But, how is this mechanically achieved? 

Is it because the clamps simply press against the casing by tightening the screw? Or is this achieved by the watch back pressing the clamps down and creating outward pressure against the casing? 

There are many many types of case construction, when a metal mov.t ring is used there are two main types:

One that uses tabs, these press down from mov.t to grooves on the case wall, going over cuts in the ring. All is secured before fitting the caseback. 

Another type uses no tabs, the screws only hold the ring to the mov.t. Sometime the ring has horizontal cuts near the top, which thin section is slightly bent up and a protruding section in the case back presses it down.

This latter type is much like the plastic mov.t spacers used on cheap and even not so cheap watches, and by the recent Seiko 5 and divers. 

Quote

Unlike a spring, this type of metal bends but doesn't want to flex back

Case tabs aren't much flexible, and often have a permanent bend. A good source of material for this kind of items is a feeler gauge.

Quote

Finding brass dial washers and case clamps, is difficult, let alone finding them in the correct size...I still need to find a good supplier for those items...Any suggestions besides eBay and Ali?

Cousins UK. 

Edited April 10, 2020 by jdm