Helvetia 1960s Depthomatic brought back to life

For a while I’ve wanted a watch with a depth gauge feature. When a 1968 Helvetia Depthomatic with original B&P came up I had to have it, even though it had some issues.

This is the watch today; I’ve told the story if how it got to this stage below.
https://i.imgur.com/ZtCv5Jn.jpg
https://i.imgur.com/uPMJxvw.jpg

The seller was very honest about some of the issues. These included the bezel not rotating, sediment preventing the caseback coming off and a very scratched up crystal. The crystal is the most critical component, as it contains the depth gauge function and is also the structural mounting for the bezel - more below.

https://i.imgur.com/PBzKZUU.jpg

The first job was to take everything apart and clean it. In the end I had to take the crystal out to get the bezel off. The depth gauge works by water entering a capillary tube that runs around the edge of the crystal. The greater the pressure, the further the water runs round the tube. The opening of the tube was completely blocked with sediment.
https://i.imgur.com/LITdEW7.jpg
https://i.imgur.com/CkNIk4M.jpg

The caseback is held on by a flanged ring, like Vostoks and Blancpains, which I really like as it wears the seal less. This one was encrusted with sediment.
https://i.imgur.com/YIRx4gP.jpg

The inside of the caseback has some very interesting information.
https://i.imgur.com/fNFjl3M.jpg
Firstly, the Helvetia serial number 5758430 tallies with the date on the warranty of 1968, according to Carl’s helvetiahistory.co.uk site.

Secondly, the area ground out gives away that the original branding on the case was Nivada. As well as their own brand, they provided versions of this watch for a number of manufacturers including Helvetia. I have seen one other Helvetia with the caseback marked in exactly this way.

The dial has clearly spent many years in the sun.
https://i.imgur.com/1vM5yDI.jpg
I know people have mixed feelings about tropical dials but I love this effect. Apparently the lume is Tritium.

This is the case and the back of the bezel with most of the sediment removed.
https://i.imgur.com/oSNjUNI.jpg

The circlip holds the bezel onto the crystal. The whole thing really was filthy, but I think it was years of use in the water.
https://i.imgur.com/OuMDheb.jpg
The crystal cleaned up nicely. I was very careful pressing it into the case, as it is essentially irreplaceable and contains all of the main features of the watch including the depth gauge capillary and dial, and the bezel mount.
https://i.imgur.com/1xmIjBR.jpg

I reassembled the rest of the watch but ran into a problem. I had loosened too much the screw that holds the stem in place. This resulted in the plate it connects to detaching. Repairing this requires the dial to come off; way beyond me. In any event I felt the watch deserved a proper service so I booked it in with Olivier (.olli.)

Olivier has done a fantastic job and also told me a bit about the movement. He also had the hands relumed by James Hyman who did a great job as well.

The movement is based on an ETA 2520 ebauche, with the rotor modified to use a bearing. The three spoke balance may also be a Helvetia modification. The movement is signed Helvetia and with the calibre number ‘4094 patented’ dial side. For a Helvetia nerd like me it’s quite nice to know that this very innovative manufacturer hadn’t quite given up their ambition for in-house quality and differentiation, as they started the slide into oblivion during the ‘70s. If any ETA experts can add any details I’d be interested.

I also think the movement looks beautiful all cleaned up - it was filthy before. Olivier has it performing very well across five positions, with a good power reserve and the auto winding working perfectly.

https://i.imgur.com/RnaDElo.jpg

I have the original box and warranty paper. From that I was able to find the shop, Mazzotti, that first sold the watch. Mazzotti is in Cervia on the Adriatic coast near Ravenna, Italy. The shop doesn’t look to have changed much and in fact is still in the ownership of the Mazzotti family of the proprietor who sold this watch.
http://web.tiscali.it/orologeria/immagini/vetrine.jpg

All in all I’m delighted with my depth gauge watch, even if I will never risk trying out its main feature. I think I just need a nice original Tropic Sport strap now...
https://i.imgur.com/UUT7wKa.jpg

An unusual watch and a good result, thank you!

That looks great! And Olli's excellent at restoring, repairing and servicing watches.

A good read and a very interesting watch.

The clean up is very good and the watch looks a treat now.




Mitch

Many thanks, always enjoy reading about the unusual being brought back to life...

Very cool - I know you won't try it in deep water, but does the depth gauge mechanism work now you've cleaned it up or does it need more pressure than you're happy to subject it to, to test it?

M

Excellent post and a nice watch. I have never seen this or the Nivada version in the wild.

Thanks for all the kind comments

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Originally Posted by snowman

Very cool - I know you won't try it in deep water, but does the depth gauge mechanism work now you've cleaned it up or does it need more pressure than you're happy to subject it to, to test it?

M

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The depth gauge would probably work but requires an absolutely water tight seal between the sides of the crystal and the case, not just at the bottom where the original gasket is still in place. The chances of both being sealed are remote so even going down to 2m would be too much of a risk I think. I’d love to see it working though.

Very interesting write up Simon, and thank you very much for the kind words!

Nice write up and great to see another unusual/rare watch saved :applouse:

Never seen one of these before and thought Nivada manufactured the only version . Interesting to learn they made them for other manufacturers.
Lovely to see the old watch shop in Italy still going and not been turned into a Boutique
It's a really special piece and is looking great after everyone's hard work.

Quote:

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Originally Posted by alfat33

Thanks for all the kind comments



The depth gauge would probably work but requires an absolutely water tight seal between the sides of the crystal and the case, not just at the bottom where the original gasket is still in place. The chances of both being sealed are remote so even going down to 2m would be too much of a risk I think. I’d love to see it working though.

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Yeah, makes sense - Great watch, though.

I can't get excited about a different coloured font on JAFR, but I love these unique watches.

M

Quote:

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Originally Posted by Robbo12

Never seen one of these before and thought Nivada manufactured the only version . Interesting to learn they made them for other manufacturers.
Lovely to see the old watch shop in Italy still going and not been turned into a Boutique
It's a really special piece and is looking great after everyone's hard work.

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Thanks. I think that Nivada probably sold the case and dial to Helvetia who then rebranded the dial and caseback and fitted their own movement.

Researching Helvetia during this time is very difficult. They became part of ASUAG around this time and there don’t seem to be any records around.

Quote:

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Originally Posted by snowman

Yeah, makes sense - Great watch, though.

I can't get excited about a different coloured font on JAFR, but I love these unique watches.

M

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JAFR took me a while [emoji1787]

That's a lovely outcome to a project and clearly provides extra pleasure every time you wear it as a result.
I started a thread a while back about restoration projects as I thought it might be useful to have a single source of information on the topic. Knowing how it looked previously does add something special over a non-restored watch.

Sent from my HD1903 using Tapatalk

Lovely looking watch and great to see the restoration process. I'm a sucker for baton markered indices as well. Really like all the little design features that have gone into it as well, the way the case back attaches and the depth gauge.

Lovely write-up and story. The end result looks brilliant. Lovely to see something like that brought back to life.

Great read!

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Originally Posted by Tailyn

Great read!

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Calm down dear.

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Originally Posted by tomp

Lovely looking watch and great to see the restoration process. I'm a sucker for baton markered indices as well. Really like all the little design features that have gone into it as well, the way the case back attaches and the depth gauge.

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The dial is definitely one of my favourite parts, I love the batons in conjunction with the 3-6-9-12. The lume has aged beautifully, and James did a great job of matching the colour and texture in the hands.

There is a later version with a cushion shaped case and a funky ‘70s look. I like that as well but it doesn’t have quite the same charm for me.

I think the addition of the cushion case would be too much. With the watch dial, the inner bezel and the outer bezel I think the round case suits it better.

Just seen this. What a cracking looking piece!

I love unusual vintage stuff like this and it certainly looks good after the renovation.

Well done.

Well done Simon for finding such an interesting watch and for posting about it - it's nice to see the work of a single-brand obessive, particularly down the path less-trodden. It's also good to see the other jobs passing over Olivier's and James' bench. was there not a possibility of testing the depth gauge with the movement out - or have I missed something really fundamental. I'm looking forward to seeing this in the metal at some stage. A tropic strap could suit it and I'd say you could also try some funky colours.

Quote:

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Originally Posted by Carlton-Browne

Was there not a possibility of testing the depth gauge with the movement out - or have I missed something really fundamental. I'm looking forward to seeing this in the metal at some stage. A tropic strap could suit it and I'd say you could also try some funky colours.

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Cheers Alan, thanks. I’ll definitely bring it along next time we meet up.

The depth gauge could have been tested with the movement out, the configuration would allow for that. To be honest I didn’t think of it before and between me and Olli we had some fun getting the crystal properly located so an opportunity didn’t arise. Maybe I’ll give it a go in the future, after a few drinks.

It occurred to me there is a bit of a design flaw, as salt water in the capillary is always going to leave a bit of salt residue after use inside the tube which a quick rinse in fresh water wouldn’t get out. I doubt many functioned for long to be honest. I like to think this one was used by some old Italian skindiver gradually getting more silted up until it was put in a drawer.

I’d be interested if anyone else has a similar depth gauge watch and has actually tried it out, or even if not.

I’ve got a funky tropic strap idea, although the lugs are 21mm so I’ll have to take a chance on a 22mm tropic fitting. I thought about a mesh strap as well but the tropic is the favourite at the moment.

A quick update now that my new strap has arrived. It’s a NOS Tropic Sport with the original buckle, just the right period for the watch and I can now see why people like them so much compared to the modern silicone ones. I’m very pleased with it.
https://uploads.tapatalk-cdn.com/202...a52c2a1c92.jpg
https://uploads.tapatalk-cdn.com/202...b7c565bea4.jpg
https://uploads.tapatalk-cdn.com/202...36aec6004f.jpg

Great post, always nice to learn about something new.

The tropic does suit it rather well, good choice!

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Originally Posted by ed335d

Great post, always nice to learn about something new.

The tropic does suit it rather well, good choice!

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Cheers Ed [emoji106]

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Originally Posted by alfat33

For a while I’ve wanted a watch with a depth gauge feature. When a 1968 Helvetia Depthomatic with original B&P came up I had to have it, even though it had some issues.

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Don't know how I missed this one Simon it really looks great now it's cleaned up! You've done a brilliant job with it. (Thanks for the link to the site too! Her is the serial number lookup for those that need it https://www.helvetiahistory.co.uk/serial-numbers)

These are a couple of my favourite Helvetia restoration projects:

https://i.imgur.com/Q1o1a5nl.jpg https://i.imgur.com/cVg0J2yl.jpg

https://i.imgur.com/xlWeMnHl.jpg https://i.imgur.com/HdHQ4kZl.jpg

Thanks. Carl.

Quote:

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Originally Posted by alfat33

Thanks. I think that Nivada probably sold the case and dial to Helvetia who then rebranded the dial and caseback and fitted their own movement.

Researching Helvetia during this time is very difficult. They became part of ASUAG around this time and there don’t seem to be any records around.

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It's a shame there is not more around about this time. There are a lot of movement references, catalogues, adverts, patents etc. around for the earlier years but hardly anything from when Helvetia was one of the founding members of SGT in 1968. I think they were doing a lot of modifications until then as you say even though they had stopped producing their completely in-house movements. It was General Watch Co, which seemed to have split off Helvetia, that joined AUSAG a bit later.

Thanks. Carl.

Thanks for straightening me out on that Carl, as you say there doesn’t seem to be any definitive information around about this era.

Quote:

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Originally Posted by alfat33

Thanks for straightening me out on that Carl, as you say there doesn’t seem to be any definitive information around about this era.

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Sorry Simon don't want you to think I was nit picking! That wasn't my intention. It's not clear at all and but they are in the list of founding members of SGT and I've seen the odd ad. It does seem strange that they spilt from General Watch Co as they were pretty much one and the same by then. I think General Watch Co must have just been nothing but a trading name without Helvetia.

Anyway that's all by the by, you have a fantastic watch there I am jealous!

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Originally Posted by enfield

Sorry Simon don't want you to think I was nit picking! That wasn't my intention. It's not clear at all and but they are in the list of founding members of SGT and I've seen the odd ad. It does seem strange that they spilt from General Watch Co as they were pretty much one and the same by then. I think General Watch Co must have just been nothing but a trading name without Helvetia.

Anyway that's all by the by, you have a fantastic watch there I am jealous!

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Haha, not at all Carl, I’m just too tired in this heat to type properly :). I do recall seeing them being in SGT as well but saw some contradictory information more recently, not realising that Helvetia and General Watch Co. split. Hard to imagine why but no doubt pretty much lost information now.

Thanks again for the comments, I must say I am enjoying wearing it. I have to get the waterproof pocket watch properly fixed up next I think.

I really enjoy these sort of posts. It’s great to see a lovely looking watch brought back in to use.
I find vintage watches much more interesting that newer models. I like a watch with patina, it makes them unique. I can’t help think that modern watches won’t have the same charm in 50 years time. And that watch has charm in spade fulls.
Thanks
John

Just for comparison here are some pictures of the Nivada equivalent, currently for sale on eBay. This is essentially the same watch with a different dial and the small movement differences pointed out by .olli.

https://uploads.tapatalk-cdn.com/202...ab83f6b279.jpg


The inside of the caseback shows the original markings, before the Nivada branding was machined off and the Helvetia serial added. The Brevet/Patent reference remains the same of course.
https://uploads.tapatalk-cdn.com/202...fdb9c84af6.jpg

The rotor is mounted using a bush rather than the bearing of the Helvetia version.

Nivada:
https://uploads.tapatalk-cdn.com/202...6915e952d9.jpg

Helvetia:
https://uploads.tapatalk-cdn.com/202...856245b5f1.jpg

It’s difficult to see the Nivada balance but it looks like 2 spokes rather than the 3 of the Helvetia.
https://uploads.tapatalk-cdn.com/202...4f2c8911bc.jpg