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Swapping a case on a Bronzo

Woundup

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When I bought my 671 it had a great deal of forced patina on it - I prefer the natural patina from age.

To remove the forced patina (lots of crusty green areas) I used a couple of denture cleaning tablets and submersed the watch for about 15 minutes. It did an amazing job of stripping the patina but left a very pink finish. Did some research and found a recommendation to use 'detoxifying' toothpaste and just scrub away at it. I didn't take any before shots but here is the result after the brushing (it actually looks more pink in these pictures than to the naked eye).





 
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Liondeer

Getting To Know The Place
7/6/21
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When I bought my 671 it had a great deal of forced patina on it - I prefer the natural patina from age.

To remove the forced patina (lots of crusty green areas) I used a couple of denture cleaning tablets and submersed the watch for about 15 minutes. It did an amazing job of stripping the patina but left a very pink finish. Did some research and found a recommendation to use 'detoxifying' toothpaste and just scrub away at it. I didn't take any before shots but here is the result after the brushing (it actually looks more pink in these pictures than to the naked eye).


Interesting. Looking at your 671, at least to my eye and on my screen, it looks a lot less pink than JayBee0815's 382 or my soon to arrive 507.

I'd actually be quite happy with that case colour as base on which to a build natural patina - which I much prefer also.
 

JayBee0815

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Looking again at the pictures you posted, it appears that after the vinegar bath your Bronzo turned to a piglet colour that is very like the pics of the Pronzo I've ordered that I put in my opening post.

Then looking at the pics of your Bronzo redeemed from its piglet status, I see that the two pics show very different colours.
I presume the more red one (first pic) is closer to reality but I'd be interested in knowing, as what you have achieved with salt water
might also be achievable with my Pronzo, when it arrives.

Also, how long did you leave it in the salt-water, and was it sea-water or just table-salt dissolved in water?


Ok, lets start from the beginning. I bought my 382 on M2M. The watch is a early VSF and is around three years old. It had developed some "brownish" patina, which is not really my taste.

Before:


So I wanted to "reset" the look of the bronze to factory state. Then I made the mistake to think "the more the better", checked the gaskets and then let the watch lie in a glass of vinegar for around an hour.

After that the watch was not only "pink" but also had a glossy, shiny surface. Not comparable to your watch, that seems to have a structured, grainy surface. It seems that the strong acid has washed out the tin form the alloy, so the surface was kind of "pure" copper. Then I searched for help on the net but could not find a fitting answer to my specific problem. So I talked to a friend, who is a kind of expert on metal processing. He told me, that the bronze surface will come back but it takes time ... maybe a long time. He said, I can force this process with ammonium-citrat in a weak alkaline solution (ph9). But as I have no access to a chem lab and the base chemicals in a reasonable container-size, he gave the tipp to use some classic bronze polish like Brasso and right after this a treatment with normal salt water. Thats is what a did. I wrapped some toilet paper soaked with Brasso around the watch over night and then gave her a bath in salt water (maximum sale concentration) for the rest of the day then took the watch out of the brine without cleaning and just waited one or two further day till the old color came back and a forced patina begann to developed.

But this was only a kind of fast forward. This seems to be a process, that also happens without this treatment but then takes much much longer. But your watch is not that "ruined". It has a structured surface (and so more contact surface for the normal reaction with air, salt and so on), so it might not take too long.

To the different colors: That is the normal light effect. One picture is made in natural daylight, the other indoor.

And one last thing: There is nothing like a "Gen" color. If have seen so much Bronzos in the Gen- and the Rep-Boards and they all develop different color-nuances over time, depending on the use and the surrounding conditions. There also seem to be different mixtures of the alloy in different models. I have an IWC Bronzo, a Segaull Bronzo and the VSF 968, which all have a different color, different tone and develop a different patina.


So the final tipp is: There is no need for rush. Give the watch some time and see what happens. I would have destroyed this wonderful watch by a hair's breadth with my actionism. I had much luck, that I could save the watch.
 
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JayBee0815

Repoholics Anonymous
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When I bought my 671 it had a great deal of forced patina on it - I prefer the natural patina from age.

To remove the forced patina (lots of crusty green areas) I used a couple of denture cleaning tablets and submersed the watch for about 15 minutes. It did an amazing job of stripping the patina but left a very pink finish. Did some research and found a recommendation to use 'detoxifying' toothpaste and just scrub away at it. I didn't take any before shots but here is the result after the brushing (it actually looks more pink in these pictures than to the naked eye).

Thanks for the pictures. It seems that stronger agents do the "patina removing job" too good - same in my case with pure vinegar. So the conclusion might be, better to be careful and start with a soft approach.
 
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Rupert Fripp

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When I bought my 671 it had a great deal of forced patina on it - I prefer the natural patina from age.

To remove the forced patina (lots of crusty green areas) I used a couple of denture cleaning tablets and submersed the watch for about 15 minutes. It did an amazing job of stripping the patina but left a very pink finish. Did some research and found a recommendation to use 'detoxifying' toothpaste and just scrub away at it. I didn't take any before shots but here is the result after the brushing (it actually looks more pink in these pictures than to the naked eye).






That looks great! What’s the toothpaste you used?

My 968 was definitely pink when it arrived and I used light spraying of sea water to add some patina, which brings out the more gold tones.


The problem I’ve had is maintaining both a fresh shine AND keeping the gold tones.

I actually apply a very thin layer of natural bees wax (as recommended by a bronze sculptor) which massively slows down its patina process. It’s a way of maintaining the look you want for longer.
 

Liondeer

Getting To Know The Place
7/6/21
37
6
8
England
It's reassuring to know that some gold tones can be brought out by using sea-water, even on a watch that arrives 'delightfully pink'.

Thanks for the info!
 

Liondeer

Getting To Know The Place
7/6/21
37
6
8
England
Ok, lets start from the beginning. I bought my 382 on M2M. The watch is a early VSF and is around three years old. It had developed some "brownish" patina, which is not really my taste.

Before:


So I wanted to "reset" the look of the bronze to factory state. Then I made the mistake to think "the more the better", checked the gaskets and then let the watch lie in a glass of vinegar for around an hour.

After that the watch was not only "pink" but also had a glossy, shiny surface. Not comparable to your watch, that seems to have a structured, grainy surface. It seems that the strong acid has washed out the tin form the alloy, so the surface was kind of "pure" copper. Then I searched for help on the net but could not find a fitting answer to my specific problem. So I talked to a friend, who is a kind of expert on metal processing. He told me, that the bronze surface will come back but it takes time ... maybe a long time. He said, I can force this process with ammonium-citrat in a weak alkaline solution (ph9). But as I have no access to a chem lab and the base chemicals in a reasonable container-size, he gave the tipp to use some classic bronze polish like Brasso and right after this a treatment with normal salt water. Thats is what a did. I wrapped some toilet paper soaked with Brasso around the watch over night and then gave her a bath in salt water (maximum sale concentration) for the rest of the day then took the watch out of the brine without cleaning and just waited one or two further day till the old color came back and a forced patina begann to developed.

But this was only a kind of fast forward. This seems to be a process, that also happens without this treatment but then takes much much longer. But your watch is not that "ruined". It has a structured surface (and so more contact surface for the normal reaction with air, salt and so on), so it might not take too long.

To the different colors: That is the normal light effect. One picture is made in natural daylight, the other indoor.

And one last thing: There is nothing like a "Gen" color. If have seen so much Bronzos in the Gen- and the Rep-Boards and they all develop different color-nuances over time, depending on the use and the surrounding conditions. There also seem to be different mixtures of the alloy in different models. I have an IWC Bronzo, a Segaull Bronzo and the VSF 968, which all have a different color, different tone and develop a different patina.


So the final tipp is: There is no need for rush. Give the watch some time and see what happens. I would have destroyed this wonderful watch by a hair's breadth with my actionism. I had much luck, that I could save the watch.

Thanks for much for getting back to me with such a detailed and well-explained response.
The colour of your 382 in the first pic is precisely the kind of brown or reddish brown that I want to avoid also.

I'm really glad I started this thread now, as I can hopefully learn from your experience.
I'm sure I would never have thought to wrap the watch in Brasso soaked tissue before adding salt water, and now I have these options
should I have to redeem my watch from any over-zealous actions (of course best not take them in the first place, as you point out....)

I agree with you that there is no one bronze tone, but rather lots of different bronze colours depending on what is the alloy, and in
what proportions. Personally I prefer bronze with more tin or aluminium and less coppper, but now whatever is in my 507
I feel there is a possibility to nudge it toward the colour I want - after first waiting to see what develops naturally of course!