Removing friction fit bezel with a case knife without destroying the thing.

[Birbdad]

So i have the case to a brand new snxs seiko. There's only a bit of information on swapping the crystal for a sapphire i bought but everybody says it's straight forward which it of course isn't. There's a friction fit bezel that must be removed to remove the crystal. Seiko was good enough to design it to open with a case knife and provided a notch at 12 and 6 oclock position. The people who have removed it said it was easy, stick a case knife in the notch, lever it up and it came right off! Well iv'e been at this for 25 minutes and have managed to destroy the bezel and the case and the bezel has budged maybe a 10th of a milimeter on one side and not on the other. Does anybody have any advice on how you open a bezel like this that's designed to open with a case knife without destroying it?  I MIGHT be able to buff out the damage but i probably just pissed away 90 dollars.

-

[RichardHarris123]

These are popular, someone may correct me but I think you can get away with a cheap version. 

[Birbdad]

Yeah i'm aware of those and i've heard mixed things about them. I would LOVE input from others here on whether it worked for them.

I guess i'm frustrated i want to be a pro watch maker and i seem to be the only guy who can't use a case knife for a simple job without destroying the case haha. 

FYI i DID get it off. Did the sapphire swap. It's a bit chewed up. I Guess it will be a future project for when i try to learn polishing.

[Neverenoughwatches]

31 minutes ago, Birbdad said:

Yeah i'm aware of those and i've heard mixed things about them. I would LOVE input from others here on whether it worked for them.

I guess i'm frustrated i want to be a pro watch maker and i seem to be the only guy who can't use a case knife for a simple job without destroying the case haha. 

FYI i DID get it off. Did the sapphire swap. It's a bit chewed up. I Guess it will be a future project for when i try to learn polishing.

Looking at the photos Col, the case knife just doesn't seem sharp enough, the honed angle looks too steep. The bezel removers can be a safer and more accurate option for some people, some better than others depending on your budget. Case knifes can be hit and miss tools, some casebacks will require a sharper edge than others. Handy to have a few kicking around with different edges or is often the case of having to sharpen one up to make it fit better. Most folk's go to with a tight case back and particularly a bezel where damage is so visual is a single sided razor blade. They will fit into almost any gap to make a start but not stiff enough to do any real damage if the bezel isn't shifting as long as you dont slip with them. 

Edited April 16, 2023 by Neverenoughwatches

[SpringMangler]

The bezel remover does work for some types of bezels, but others are just a sod to get off. 

For some you need to remove the bezel insert then remove the retaining spring, others, like the Squale I've been working on, need 3 hands and the patience of the pope. The bezel remover would not work on either of these bezels. 

 

[Marc]

Since you have been provided with two notches diametrically opposite each other you might want to try using two case knives simultaneously, one in each notch. This should result in a more vertical lift without canting the bezel off axis. If tolerances are really tight, which they seem to be, the axial tilt of a one sided lift may be all that is needed to bind the thing solid.

[Birbdad]

19 hours ago, Neverenoughwatches said:

Looking at the photos Col, the case knife just doesn't seem sharp enough, the honed angle looks too steep. The bezel removers can be a safer and more accurate option for some people, some better than others depending on your budget. Case knifes can be hit and miss tools, some casebacks will require a sharper edge than others. Handy to have a few kicking around with different edges or is often the case of having to sharpen one up to make it fit better. Most folk's go to with a tight case back and particularly a bezel where damage is so visual is a single sided razor blade. They will fit into almost any gap to make a start but not stiff enough to do any real damage if the bezel isn't shifting as long as you dont slip with them. 

INteresting, i assumed having a thick robust edge for prying strength was sorta how a case knife is supposed to work. In all the demos i've seen of their use they're used mainly as a prying tool. I would love to see a pic of your properly dressed case knife if you got one. I can probably reprofile the thing

 

19 hours ago, Marc said:

Since you have been provided with two notches diametrically opposite each other you might want to try using two case knives simultaneously, one in each notch. This should result in a more vertical lift without canting the bezel off axis. If tolerances are really tight, which they seem to be, the axial tilt of a one sided lift may be all that is needed to bind the thing solid.

yeah it could be. Once i got one side to move a little the other seemed to not budge at all. THe thing finally popped off when i sorta just started working my way from the partially separated side around and just jam the case knife in and gently lever it up. ONE slip though and the case and bezel are toast and it's SO slippery and easy to slip.

19 hours ago, SpringMangler said:

The bezel remover does work for some types of bezels, but others are just a sod to get off. 

For some you need to remove the bezel insert then remove the retaining spring, others, like the Squale I've been working on, need 3 hands and the patience of the pope. The bezel remover would not work on either of these bezels. 

 

Yeah unlike other seiko bezels this one is purely press fit and it actually is the sole thing retaining the crystal. THere's not even a gasket inside it which i've never seen before. It was a nightmare to get off -_-

[Neverenoughwatches]

4 hours ago, Birbdad said:

INteresting, i assumed having a thick robust edge for prying strength was sorta how a case knife is supposed to work. In all the demos i've seen of their use they're used mainly as a prying tool. I would love to see a pic of your properly dressed case knife if you got one. I can probably reprofile the thing

Different profiles will come into their own, what is being removed will usually dictate that. My thoughts are you need to push into and create a gap to have something to lift off, an over thick profiled or steep edged case knife could make that difficult.  Then forcing comes into play and control is out of the window. I'm sure other folk have different ideas, ive seen kalle of chronoglide use something that looked like a sharp bladed auto punch. He said it worked well. Here are the ones i use, all but one have a bevel on both sides, not by my doing just as they came. My favourite is the old bone handled one, its very thin and sharp but still has good stiffness to lift off, it fits into almost any gap. Ideally a prying action shouldn't be used as that will tend to cause damage, but who doesnt resort to that when things aren't shifting. The bevel edge of the caseknife should pop the bezel up, but thats not always the case if its tight. Thats usually when we feel the need to work our way around the edge lifting bit by bit. And has been mentioned lifting one edge can make the bezel and case bind against each other. Same with everything in watchreapair, its about finding which way works for you and practising that technique to get better.

Edited April 17, 2023 by Neverenoughwatches

[Birbdad]

28 minutes ago, Neverenoughwatches said:

Different profiles will come into their own, what is being removed will usually dictate that. My thoughts are you need to push into and create a gap to have something to lift off, an over thick profiled or steep edged case knife could make that difficult.  Then forcing comes into play and control is out of the window. I'm sure other folk have different ideas, ive seen kalle of chronoglide use something that looked like a sharp bladed auto punch. He said it worked well. Here are the ones i use, all but one have a bevel on both sides, not by my doing just as they came. My favourite is the old bone handled one, its very thin and sharp but still has good stiffness to lift off, it fits into almost any gap. Ideally a prying action shouldn't be used as that will tend to cause damage, but who doesnt resort to that when things are shifting. The bevel edge of the caseknife should pop the bezel up, but thats not always the case if its tight. Thats usually when we feel the need to work our way around the edge lifting bit by bit. And has been mentioned lifting one edge can make the bezel and case bind against each other. Same with everything in watchreapair, its about finding which way works for you and practising that technique to get better.

Ok. i might see what i can do with the edge on mine. it's a less cheap chinese case knife but still pretty good quality and appears to be a clone of the bergeon one. Appreciate the advice. I might not have just been using it correctly. There's just not a lot of info on the subject out there. This is the end result -_-

Brand new seiko snxs case

Edited April 17, 2023 by Birbdad

[mikepilk]

You should not "lever" but just push the blade in. That's the theory, but I gave up with case knifes as I found them too difficult to use in some cases, and it's easy to scratch the movements and dials (or draw blood )

I use one of these on bezels and case backs, works easily and no danger of slipping and damaging something.

For tight bezels, if there is very little gap to get the blade in, I sometimes work round with a razor blade just to start it.

[Neverenoughwatches]

1 hour ago, Birbdad said:

Ok. i might see what i can do with the edge on mine. it's a less cheap chinese case knife but still pretty good quality and appears to be a clone of the bergeon one. Appreciate the advice. I might not have just been using it correctly. There's just not a lot of info on the subject out there. This is the end result -_-

Brand new seiko snxs case

It happens, annoying but i wouldnt worry about it. In an ideal world if the bezel has a notch ( but not always and that might suggest it doesn't come off that way or at all ), if the case knife has a slightly steeper angle than the notch then it should push the bezel upwards and off as its pushed up against it. Thats hoping and watch repair is also far from being in an ideal world

[Birbdad]

On 4/17/2023 at 4:45 AM, mikepilk said:

You should not "lever" but just push the blade in. That's the theory, but I gave up with case knifes as I found them too difficult to use in some cases, and it's easy to scratch the movements and dials (or draw blood )

I use one of these on bezels and case backs, works easily and no danger of slipping and damaging something.

For tight bezels, if there is very little gap to get the blade in, I sometimes work round with a razor blade just to start it.

I've never seen one of those. You got a link to it? It seem to work well for you?

On 4/17/2023 at 5:10 AM, Neverenoughwatches said:

It happens, annoying but i wouldnt worry about it. In an ideal world if the bezel has a notch ( but not always and that might suggest it doesn't come off that way or at all ), if the case knife has a slightly steeper angle than the notch then it should push the bezel upwards and off as its pushed up against it. Thats hoping and watch repair is also far from being in an ideal world

I saw somebody else on my other place i hang out with watchmakers say that they often use a case knife in a similar shape as mine and lightly tap it with a hammer and just alternate sides with it.

[Neverenoughwatches]

1 hour ago, Birbdad said:

I've never seen one of those. You got a link to it? It seem to work well for you?

I saw somebody else on my other place i hang out with watchmakers say that they often use a case knife in a similar shape as mine and lightly tap it with a hammer and just alternate sides with it.

Similar principle to the tool that kalle uses. Like an auto punch, you push the blade against the case back or bezel as it reaches its tension point it releases and fires the blade forward. I wouldnt trust myself with it. I prefer the slowly slowly catch your monkey approach.  I also have the same devise that mike uses, in fact it was mike that inspired me to try it. I dont often use it, not that it doesn't work , i just rarely need anything besides a knife. 

[mikepilk]

3 hours ago, Birbdad said:

I've never seen one of those. You got a link to it? It seem to work well for you?

I saw somebody else on my other place i hang out with watchmakers say that they often use a case knife in a similar shape as mine and lightly tap it with a hammer and just alternate sides with it.

Cousins sell them for £12.95 (or you can buy the Swiss version for £69, which looks identical ,  but it's one of those tools you don't need the expensive version for it to work OK).  Or you can find them on ebay. 

Edited April 20, 2023 by mikepilk

[Birbdad]

On 4/20/2023 at 9:44 AM, mikepilk said:

Cousins sell them for £12.95 (or you can buy the Swiss version for £69, which looks identical ,  but it's one of those tools you don't need the expensive version for it to work OK).  Or you can find them on ebay. 

Sweet, if that's workin for ya i'll order one on my next cousins order. Thanks bud!

[Waggy]

On 4/16/2023 at 2:16 PM, RichardHarris123 said:

These are popular, someone may correct me but I think you can get away with a cheap version. 

I got a Chinese version of this and it works well, I think it's one tool that you can get away with the cheap version, but I'd love to know where to get replacement blades as mine are starting to show signs of wear.... can anyone point me in the right direction?

I also got the Indian version of the case back opener, and it broke at the hinge on the leaver (see below), fortunately Cousins sell just the leaver (grey bit) so I could repair cheaply.

Whilst I'm on a roll I just noticed at the weekend that my case tube tool destroyed itself (see below), looks like the white plastic (red circle) deformed allowing the case to slip, which then subjected the pusher to a side-load deforming (tear dropping) the small hole that the pusher fits into (green circle). After a close look the wall thickness of the pusher hole is VERY thin (see below) and I'm not surprised that it deformed. So maybe I need to get the good version of this tool, but looking at the Horotec version the wall thickness looks just as thin! Any ideas?

   

[Birbdad]

On 4/20/2023 at 7:41 AM, Neverenoughwatches said:

Similar principle to the tool that kalle uses. Like an auto punch, you push the blade against the case back or bezel as it reaches its tension point it releases and fires the blade forward. I wouldnt trust myself with it. I prefer the slowly slowly catch your monkey approach.  I also have the same devise that mike uses, in fact it was mike that inspired me to try it. I dont often use it, not that it doesn't work , i just rarely need anything besides a knife. 

I"m a little unclear, fires the blade forward? It looks like you just screw down to slowly put pressure on the blade till it pops up the bezel.

What do you do with a knife when the bezel is REALLY on there?
 

[Waggy]

28 minutes ago, Birbdad said:

I"m a little unclear, fires the blade forward?

I think you are conflating 2 tools, the one that fires is a bit like those spring loaded centre punches (see below), these 'shock' the case back or bezel into opening, but I only use this as a last resort as the risk of it jumping and scratching the watch or burying itself into the flesh of your hand are significant, and I've only ever used on on a case back not a bezel.

 

[Neverenoughwatches]

2 hours ago, Birbdad said:

I"m a little unclear, fires the blade forward? It looks like you just screw down to slowly put pressure on the blade till it pops up the bezel.

Sorry confused you there colin, i was referring to the guy you mentioned that uses a hammer to tap the caseknife in, kalle used an auto release tool that fires the blade out. Mike's  tool and mine does wind a blade into the case edges.

2 hours ago, Waggy said:

I think you are conflating 2 tools, the one that fires is a bit like those spring loaded centre punches (see below), these 'shock' the case back or bezel into opening, but I only use this as a last resort as the risk of it jumping and scratching the watch or burying itself into the flesh of your hand are significant, and I've only ever used on on a case back not a bezel.

 

Thats the one

2 hours ago, Birbdad said:

I"m a little unclear, fires the blade forward? It looks like you just screw down to slowly put pressure on the blade till it pops up the bezel.

What do you do with a knife when the bezel is REALLY on there?
 

Me personally I can nearly always get away with using my favourite caseknife. Being a joiner i have really strong controlled hands. The times that i do struggle then i resort to the same tool that mike posted. They are well worth getting for the price.

[Birbdad]

Ok. Yeah that spring loaded tool looks pretty violent haha.