Le Cheminant 25 jewel Master Mariner Super Compressor

[chrisdt]

Can anyone please give me guidance on the case back removal of a Le Cheminant 25 jewel Master Mariner Super Compressor?  The case back looks like a regular snap on with an even bigger gap between the back and the rest of the case to insert a case opening knife but no matter how I try I cant  seem to lever it off. Obviously I dont want to ruin the back but I'm getting ready to throw it.

Chris

[rogart63]

Pictures? 

[clockboy]

If this is the watch then it is clearly a screw back case.

[chrisdt]

Some pics but not sure they help much

Edited March 18, 2017 by chrisdt

[wls1971]

Is it definitley a Super Compressor there are two types of Super Compressor case back one is a screw down and one is a bayonet fitting both require a wrench to remove. Compressor and Compressor 2 case backs are snap on

[wls1971]

Having seen your pics you have a Compressor not a Super Compressor case so it defintley snap on

[chrisdt]

Perhaps just a compressor then but it was sold to me as a Super Compressor so if its the former its snap on and I need a jemmy?

[clockboy]

Could it split here.

[chrisdt]

Thank you clockboy I'll give it a try

Chris

[wls1971]

They can be very difficult to remove and a proper caseback opener not a knife would be the best option, they can be particually difficult if the gasket has degraded and formed a gum between back and case.

[wls1971]

No thats not the split Clockboy

Edited March 18, 2017 by wls1971

[chrisdt]

So its the split that you can see or its a front loader

[wls1971]

There are no front loading compressor watches, the back sits very flat and very tight against the case, what clock boy has pointed out is just a detail of the case

[chrisdt]

Thanks for all your help. Finally managed to free it from its home.......Seems to be an AS1906..

[wls1971]

I dont know if you have noticed or maybe you have removed it but the bezel is missing from the watch, and what is the curios word under the divers helmet on the back I can read suspe, have you a picture of the inside of the case back ?

[Neileg]

1 hour ago, wls1971 said:

I dont know if you have noticed or maybe you have removed it but the bezel is missing from the watch, and what is the curios word under the divers helmet on the back I can read suspe, have you a picture of the inside of the case back ?

Seems to say SUSPENSE

Neil

[chrisdt]

The word is SUSPENSE....Perhaps it is because you have to wait so long to see inside because the back is so difficult to remove.

The bezel came of when struggling to remove said case back....Now I cant get it back on

[clockboy]

Now and again you come across a real tight one. I purchased this tool and only use it with the tight one's but it works a treat. There are other styles but this works for me

To re-fit a tight case back or bezel you really need a case/crystal press. I prefer the screw style as these give more control.

[wls1971]

If you look on the inside of the case back there is quite often but not always a 3 to 4 digit date code usually the month and year of manufacture  seperated by a dash, SUSPENSE intresting but never seen that before

[wls1971]

"SUSPENSE" think I have found out what it is the movement is held in place with rubber blocks between the movement spacer ring and case to protect against shocks, I have a IWC yacht club that uses this kind of shock protection

[Marc]

@chrisdt I wonder if you would be good enough to post a picture of the bezel. I have what appears to be an identical Master Mariner in an EPSA Compressor case (which also says "SUSPENSE" on the back) except mine has an AS1903 inside (I suspect yours is probably also a 1903 as the 1906 is a day/date whereas the 1903 is just date).

Mine came in a job lot of stuff and is not as tidy as yours but it is on my list of projects to sort out. Mine didn't have a bezel when I got it and I assumed that it wasn't supposed to have one but you say that yours does. A pic would be most helpful as I would then know what to look out for.

Like yours mine is an absolute pig to open.

[chrisdt]

Your right about the rubber blocks wls 1971. In my opinion not a very good idea as they are starting to disintegrate and it would be almost impossible to remove them without them breaking up completely. Not impressed.

Pictures of the bezel for you @Marc

[Marc]

Thanks @chrisdt, the pics are very useful. I might even have a crack at machining up a replacement bezel myself.

I had forgotten about the rubber shock mounting of the movement to the case. This is a system that Certina have used for a long time in their DS range. I wonder if there is any published data as to how effective it is.

[chrisdt]

AS I mentioned @Marc the bezel came off but wont go back on again despite numerous attempts with 8 fingers six pairs of tweezers, 2am, frustration. (Contemplating super glue)