lifejacket light in bits.

Sailingsaves

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I found this interesting.

Took me ages to open it as expected.

Photos here.

View attachment 40251View attachment 40253View attachment 40255View attachment 40252View attachment 40254

This is over 10 years old I think.

No good as a light these days.

BUT a fine example of design and use of LITHIUM battery (made by whatever UK company that is printed on the battery). WHY? Because after these years, this battery is 2.87 Volts. Brand new rated as 3V and after all these years it has only lost 0.13V (and who knows how many times it was activated?)

Shows how good Lithium batteries are for their purpose.

Lithium batts are great for not losing potential whilst stored. NiMetalHydrides do lose potential of course.

I am going to stick in a new Lithium battery and replace the glow worm fragile filament bulb with a decent LED, seal it all up (I have a plastic welder), and bob's you uncle, I have a pretty well designed light. It also has sensible dual methods of attaching to lifejackets.
 

bitbaltic

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I found this interesting.

Took me ages to open it as expected.

Photos here.

View attachment 40251View attachment 40253View attachment 40255View attachment 40252View attachment 40254

This is over 10 years old I think.

No good as a light these days.

BUT a fine example of design and use of LITHIUM battery (made by whatever UK company that is printed on the battery). WHY? Because after these years, this battery is 2.87 Volts. Brand new rated as 3V and after all these years it has only lost 0.13V (and who knows how many times it was activated?)

Shows how good Lithium batteries are for their purpose.

Lithium batts are great for not losing potential whilst stored. NiMetalHydrides do lose potential of course.

I am going to stick in a new Lithium battery and replace the glow worm fragile filament bulb with a decent LED, seal it all up (I have a plastic welder), and bob's you uncle, I have a pretty well designed light. It also has sensible dual methods of attaching to lifejackets.

Yeah, but ....

I believe some of these older lights have a design where they only light up as long as the power pack is immersed in water. That is, if they ride up out of the briny on your LJ while the rest of you is still floating in the drink, they turn off. I'd be sure this design is not one of these old school jobs before you go to the trouble to repower it. If in any doubt, I'd take my fifteen quid to the chandlers and start over.

Just an opinion, of course. PBO is frequented by old blokes who love this sort of thing.

Cheers
 

Sailingsaves

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Yeah, but ....

I believe some of these older lights have a design where they only light up as long as the power pack is immersed in water. That is, if they ride up out of the briny on your LJ while the rest of you is still floating in the drink, they turn off. I'd be sure this design is not one of these old school jobs before you go to the trouble to repower it. If in any doubt, I'd take my fifteen quid to the chandlers and start over.

Just an opinion, of course. PBO is frequented by old blokes who love this sort of thing.

Cheers

Good point. This one has a plastic plug that has to be pulled out to initiate light (and then hangs down ready to be inserted to stop light).

So that is good and bad.

Another light (I pull lots apart to examine them) is the type you mention, salt water makes the circuit.

The first design would not light if person unconscious, but would stay alight if moved out of water as you state.

Conclusion, a good design will incorporate both scenarios.

I am just tinkering and examining and fixing and making things better _ it is how I learn stuff. I only sail a dinghy these days and in daylight so have no need of a light (but I have several types to use if / when I do sail - so many I'll probably sink with the weight!)

I haven't looked at modern lights yet _ they may have it well sorted.

I was just impressed with the old battery and string and other attachments.
 

William_H

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Regarding replacing the light with LED. Yes far more light and more efficient than incadescant globe. However the filament globe has an all round light radiation pattern. LEDs have a directional radiation pattern. The LED witha hemisherical top cylindrical shape can have 15 degree radiation which makes them great for a torch directing light. The SMC types as found in multiple LED bulbs have a wider light dispersion but still essentially in one direction. But devils to mount and solder being sop small. So for LED light you will need 3 or 4 min LED facing in diferent azimuth orientation plus one for upwards to match the pattern of the incandescant bulb. Of course the opaque cover may suffice to distribute light from one LED in enough directions but will be much less intense. All good pastime for winter.
For the OP the lithium cell for long life is of course vastly different to a Lithium rechargeable cell. The rechargeable type are fairly common but the type you want is only used in emergency gear and memory backup. (and watches of course but far too small)
good luck olewill
 
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