|Posted by Derek on October 24, 2011 at 10:40 AM|
Tutorial: Changing the battery in a Darth SBBN011
Though the battery in my SBBN011 is not dead or showing signs of giving up, I don’t know when it was changed, so it could die anytime soon, and as I have the whole day to myself, I thought I would give it a go.
If you are brave enough and have a lot of patience and the right tools then the following might help – but I won’t take any responsibility if you mess up.
Firstly some details on this watch, the model number is SBN0011, 7C46-OAAO. It has a Seiko 7C46, hi-torque 7 jewelled movement designed for the Tuna series of divers. For more interesting information on these movements check out the link below written by Poseidon-Jim…..
The calibre 7C46 is used in the 600m and 1000m Seiko divers and is designed for use in saturation diving using Helium gas. The one piece case consists of Titanium and Ceramic, there is also some stainless steel in there, but to find out which part contains what; I found this post, by Jim from Sept 2010;
The case is always spoken of by the Japanese as a single unit, but as we know the casei s made up of more than just the body alone. You have the bezel and inner screwdown crystal rings and even an inner iron/SS antimagnetic plate inside theTitanium alloy case, and the shroud screws are IP coated stainless steel or could also be titanium alloy, and you have the inner crown and stem parts that are no doubt Stainless steel.
Titanium is also in the stainless steel family as it is steel, but a hi-grade type that is lighter and harder than stainless steel.
The body or main case is Black IP coated titanium with an TIHCCE (ceramics) shroud.
The bezel I think is either titanium IP coated stainless steel or titanium.
So you see, the whole case or body is actually a mixture of mostly titanium with some stainless steel parts (SS & Titanium) and the shroud is (IPcoated Ti Ceramics).
The battery required for this model is SEIKO SR43SW (301) and should last approximately 5 years, I bought a Maxell from Cousins.
For details on the watch here is a pdf from Seiko
OK, let’s make a start, what tools for the job? – BTW the hex screws shroud requires a 1.5mm Hex key, Jaxa type case remover, Blade to pop off the bezel, small screwdriver for the battery retaining screw, case/movement holder.
Pic 1 –Remove the Hex screws
Pic 2 –Shroud removed, revealing dirt – I cleaned this up to avoid any getting in the case later on.
Pic 3 –Slipping a flat blade between the case and bezel, pop off the bezel – this should be easy. In this pic you can see the two flat bezel springs still in thecase.
Pic 4 - The flat bezel springs sit in a groove and are easily removed with a small screwdriver or similar
Pic 5 - I have removed the strap and popped the case into a movement/case holder, you will need to secure the case so that you can get good leverage to unscrew the crystal retaining ring.
Pic 6 –Here the crystal retaining screw has been removed using a Jaxa type caseback remover. Ensure the remover sits properly within three grooves, apply even pressure and unscrew anti clockwise. These are normally hand tight some can be tough but keep even pressure or you may slip and scratch the crystal orcase.
Pic 7 –Under the crystal retaining ring sits a nylon band which ensures the rubber gasket below it is evenly pressed and shaped to provide a maximum seal.
Pic 8 –This shows the crystal out but the crystal gasket still in place. Removing crystal I found to be quite tricky, it sits on the rubber gasket under pressure so it is well bedded in and requires very gentle persuasion with a small flatend object, preferable made of plastic or wood. You can use a flat head screwdriver, but you can end up damaging the gasket or the crystal.
Pic 9 –This shows the crystal far left, then the rubber gasket and the minute chapter ring. The chapter ring has two grooves cut into it that match to one dial feet and the crown. This ensures that the markers line up perfectly when refitting.
Pic 10 –Here you see a gasket that sits around the movement, this should be removed to get access to the crown release button.
Pic 11 –This shows the crown release button and it sits just north of the crown,unscrew the crown, on the two occasions I have removed the crown from a 7C46 I didn’t pull it out to 1st or 2nd position prior to removal, just unscrew the crown, depress gently the release button and wiggle the crown with gentle pulling force, and it should pop out.
Pic 12 –Case, movement and crown
Pic 13 –With the crown removed there is nothing holding the movement in the case, so be careful and turn the case over ensuring you can grip the edges of the movement/dial. Then you will need to pop the movement into the holder. Remove completely the screw holding the battery retaining clip, don’t think you can nudge the battery out, you won’t. Replace battery and pop the retaining clip back and spend 30 minutes putting the little bugger of a screw back in :(.
Pic 14& 15 – Here is the case all nicely cleaned, I really like this case, and you can see it is a great piece of design and engineering, each groove has a purpose and the base has a raised plate where the movement sits.
Now thebattery is replaced and you have cleaned and greased (very little required) the gaskets put it back together. Do you need to replace the gaskets? Well some will swear by it, but I have found that certainly on these modern Seiko’s the gasket shape is fine and can be used again, if it has deteriorated or out of shape then of course in needs replacing.
Pic 16 –Once completed put on wrist and admire your handy work J
I want to pay credit to Dr Seiko for his tutorial on the 1000m divers, without I wouldn’t have ever dared to attempt this.