Breitling case back removal

[Bonefixer]

A colleague has entrusted me with servicing his Breitling 92 Navitimer. I've fallen at the first hurdle as I can't get the back off!

 Rubber ball wouldn't do it. It's a 14 sided polygonal back, 30mm. I tried supergluing a nut on the back but it sheared off when trying a spanner. 
 

Can I try the same trick with some epoxy? Will I be able to remove epoxy with acetone? Or do I just have to shell out on a die to remove the back and hope I select the right one?

[AndyGSi]

What size is it across the flats and can you post a photo.

[mikepilk]

You can buy tools for this from Amazon or ebay

[AndyGSi]

4 minutes ago, mikepilk said:

You can buy tools for this from Amazon or ebay

All the ones I've seen of these are either 12 or 15 sided.

[RichardHarris123]

What type of opener do you have? 

[AndyGSi]

21 minutes ago, RichardHarris123 said:

What type of opener do you have? 

Being a 38mm case I expect that's the size needed.

[HectorLooi]

2 hours ago, Bonefixer said:

Can I try the same trick with some epoxy? Will I be able to remove epoxy with acetone?

Yes. You can use epoxy. No, acetone won't dissolve epoxy. But epoxy comes off quite easily when heated.

I would use 5-ton epoxy and glue a huge nut to it. Then let it cure 24 hours.

Or you could do it the redneck way and use a big adjustable wrench. 

[mbwatch]

I am surprised the superglue didn't hold. Did you allow it to cure 24 hours?

[RichardHarris123]

Try a flanged nut , more surface area  

[Bonefixer]

21 minutes ago, mbwatch said:

I am surprised the superglue didn't hold. Did you allow it to cure 24 hours?

More like 5 minutes. I was under the impression that superglue was pretty much instantaneous. 
 

i think the problem may be the surface isn't flat - it's got an embossed emblem - so the contact area is restricted. Which is why I think a blob of epoxy might be the solution. 

1 hour ago, RichardHarris123 said:

What type of opener do you have? 

That is probably the one, just trying to avoid yet another cousins order. 

[AndyGSi]

What size nut were you trying to glue or as mentioned by @HectorLooi have you got a large adjustable spanner.

[mbwatch]

23 minutes ago, Bonefixer said:

More like 5 minutes. I was under the impression that superglue was pretty much instantaneous. 

Ah. It will stick 2 things together in a couple of minutes but will not become uniformly hard and resist shearing until the next day.

[Neverenoughwatches]

9 hours ago, Bonefixer said:

A colleague has entrusted me with servicing his Breitling 92 Navitimer. I've fallen at the first hurdle as I can't get the back off!

 Rubber ball wouldn't do it. It's a 14 sided polygonal back, 30mm. I tried supergluing a nut on the back but it sheared off when trying a spanner. 
 

Can I try the same trick with some epoxy? Will I be able to remove epoxy with acetone? Or do I just have to shell out on a die to remove the back and hope I select the right one?

Did you clamp up the nut when you glued it ? 

5 hours ago, Bonefixer said:

More like 5 minutes. I was under the impression that superglue was pretty much instantaneous. 
 

i think the problem may be the surface isn't flat - it's got an embossed emblem - so the contact area is restricted. Which is why I think a blob of epoxy might be the solution. 

That is probably the one, just trying to avoid yet another cousins order. 

Nut needs compression to get the best fixture possible, and like HectorLooi and Andy have said, biggest nut you can find that fits the back,ie the most surface area coverage. Any engraving will fill in with glue as long as the back is flat and not bowed it will work. This trick has never failed me, cyanoacrylate is a very strong glue when applied correctly, if the operation isn't good then the fix can be really quite crap. It also comes in different strengths , thicker takes longer to fast set but is the strongest. All superglue has an instant set but full cure time is well past instant. For your clamp , use a screwback press, obviously a good fitting die to the front with a cloth or plastic sheet between it and the die. I guarantee it will work if you get the application right .

Make sure you remove all of the previous attempt, you want two good clean surfaces, no greasy fingerprings so wipe the nut and back over with IPA once you have the first lot of superglue off.

[CYCLOPS]

if your going to do nice watches I would invest in some type of case opener, a simple LG wrench would probably do the trick and last a lifetime....good luck with the nut hack

[VWatchie]

What surprises me is why case backs are screwed on so excessively tight. If the lugs are sharp, I usually wear a leather glove on my non-dominant hand to get a better grip on the watch and then tighten the case back as much as possible using a rubber ball. That is more than enough to keep the watch water-resistant, especially with a well-lubricated gasket.

My advice to everyone, including manufacturers: Stop tightening case backs with tools designed to open them. There’s a reason they’re called "case back openers"!

[Bonefixer]

On 3/20/2025 at 7:28 AM, CYCLOPS said:

if your going to do nice watches I would invest in some type of case opener, a simple LG wrench would probably do the trick and last a lifetime....good luck with the nut hack

I've got a bench mounted one like a Bergeon, just a good quality Chinese version that has never let me down. I just don't have a 14-sided 30mm Breitling specific die to go with it. Got a set of Rolex (knock off) ones but the Breitling sets are quite expensive and incomplete anyway. 

And some feedback - it's off! Superglue, when allowed more than 30 seconds to fully cure, combined with a bigger nut, did the job. 
 

inside the watch is a standard ETA base calibre with a chronograph module. I think it's the same as the Omega I tackled, so should be good from here