T<25 Lume Life

[mjm800]

I have two T<25 watches one is an N Serial GMT Master Pepsi the other an S serial No Date, Non-COSC Sub.

The lume on the Sub is completely dead while the lume on the older GMT is alive and well.

I am not the original owner of either watch so I am wondering why one is dead while the other still lumes. Some history that I have is the GMT was clearly well cared for it looks brand new and has kept perfect time since buying. The Sub came in a bit beat up and was badly in need of a full service.

Perhaps the Sub lived a more robust life in the outdoors while the GMT was a pampered watch only worn sparingly.

[usbzoso]

http://en.wikipedia.org/wiki/Tritium - half life is 12 years

[Tools]

Tritium has a half life of ~12 years.. That means that after 12 years, it is emitting half of the energy that it did originally.. another 12 years, and it is again half that..

Generally, the tritium is still radioactive, but to a lesser extent and it cannot excite the phosphors in the paint matrix..

So, likely in your case, one watch has decayed more than the other and cannot make the paint glow. Could be because the paint used was on the shelf for a couple of years when used, or it could be that the paint matrix does not have sufficient phosphors to be excited by what little energy is left..

[mjm800]

Thanks for the info!

[cameronweiss]

any moisture getting in contact with the tritium lume will cause it to loose its function as lume. So maybe the Sub got some moisture in the case at sometime during its life.

[Paulie 50]

Originally Posted by Tools

Tritium has a half life of ~12 years.. That means that after 12 years, it is emitting half of the energy that it did originally.. another 12 years, and it is again half that..

Generally, the tritium is still radioactive, but to a lesser extent and it cannot excite the phosphors in the paint matrix..

So, likely in your case, one watch has decayed more than the other and cannot make the paint glow. Could be because the paint used was on the shelf for a couple of years when used, or it could be that the paint matrix does not have sufficient phosphors to be excited by what little energy is left..

Larry, i am wondering if you can help please, i own a SD 16600. U serial.
A couple of years ago i changed the insert, i still have the original one which i put away in the box, my question is my friend , is the new insert a Tritium pearl, the ref. no. is 315-16660-81. Lumi y-09. Thank you in anticipation.
PS. the old insert is showing patination on the pearl.

[rolexpawn]

Another reason could be the one that still glows is a service dial.

[SALTY]

My "W" 16710 c.1995 has lost its lume. Love the watch and it has sentimental value but would need Bond's cigarette lighter to tell the time after hours.

[subtona]

i bought an E serial sub in 1991, the lume was incredible,
in 1996 the watch needed a service and in the process of service the original dial was scratched. rolex replaced it with another tritium dial but it never glowed the same and it is now completely dead.

ps the watch never had any moisture inside and the crown was seldom opened as it was worn daily.

i suspect either the tritium quality control was varied or perhaps the tritium content was lessoned as the years passed by?

[terrenceterrence]

Originally Posted by subtona

i bought an E serial sub in 1991, the lume was incredible,
in 1996 the watch needed a service and in the process of service the original dial was scratched. rolex replaced it with another tritium dial but it never glowed the same and it is now completely dead.

ps the watch never had any moisture inside and the crown was seldom opened as it was worn daily.

i suspect either the tritium quality control was varied or perhaps the tritium content was lessoned as the years passed by?

or maybe the dial that they replaced with has been produced and kept sitting in the inventory for quite some time?

thus when it reached your watch it's just a few years shy of losing it's lume

[subtona]

Originally Posted by terrenceterrence

or maybe the dial that they replaced with has been produced and kept sitting in the inventory for quite some time?

thus when it reached your watch it's just a few years shy of losing it's lume

good possibility...?

but the dial had a slight revision over my original dial....
the lettering was slightly raised (more modern) vs my original which appeared flat painted. at the time i thought it was an improvement, but in hindsight i would have preferred to keep it original.

i guess its impossible to know for sure?

[warren G.]

My T-series SD lost it's lume. I kinda miss it, but I'll live.