Dive Lights Using Mineral Oil?

gcbryan

Flashlight Enthusiast
Joined
Oct 19, 2009
Messages
2,473
Location
Seattle,WA
I've heard of divers filing regular flash lights with mineral oil and using them as dive lights.

Other than being potentially messy does this work? Since this is the dive light forum I figured some of you had probably tried this in years past and was just curious as to what you learned.

Does this have any adverse impact on li-ion batteries for instance?

I would rather pick someone else's brain and learn from their mistakes if possible!

This must impact the quality of the light output as well I would think.

While I'm brain picking:grin2:...has anyone experimented with potting led's, circuit boards or any other components in an effort to eliminate the damage should a light flood?

I'm sure it's better to just design a light that doesn't flood but in the name of exploring all aspects of dive light construction/techniques I thought I'd ask.
 
Last edited:

Dez

Newly Enlightened
Joined
Dec 14, 2009
Messages
54
Location
Sweden
I've heard of divers filing regular flash lights with mineral oil and using them as dive lights.

Other than being potentially messy does this work? Since this is the dive light forum I figured some of you had probably tried this in years past and was just curious as to what you learned.

Does this have any adverse impact on li-ion batteries for instance?

I would rather pick someone else's brain and learn from their mistakes if possible!

This must impact the quality of the light output as well I would think.

While I'm brain picking:grin2:...has anyone experimented with potting led's, circuit boards or any other components in an effort to eliminate the damage should a light flood?

I'm sure it's better to just design a light that doesn't flood but in the name of exploring all aspects of dive light construction/techniques I thought I'd ask.

I have been working with diving for 7 years and never seen anything like that. Interesting thought though.. But I dont think its really worth it.

Hehe, but then again, I rarely use a light at all under water. Even at night as long as its a good moon out. =)
 

Goldigger

Enlightened
Joined
Mar 17, 2009
Messages
327
Location
London UK
Why dont you fill the ugly light up with oil and let us know..
Oh hold on thats an unfair test, we wont know if the oil killed it or the salt water :D


Not to mention the environmental impact if all ugly light owners do the same.. :D
 

Packhorse

Flashlight Enthusiast
Joined
Nov 29, 2007
Messages
1,912
Location
New Zealand
Filling items with oil is more about reducing the effects of external pressure.
If you get rid of all the air inside then there is nothing to compress and the crush rating of the device is increased dramatically.

Im not sure doing it to a light is such a good idea. Its going to be very messy every time you change the batteries.
 

DM51

Flashaholic
Joined
Oct 31, 2006
Messages
13,338
Location
Borg cube #51
Goldigger... this is a family-oriented forum. Crude references of that type are not permitted.
 

Linger

Flashlight Enthusiast
Joined
Feb 17, 2009
Messages
1,437
Location
Kingston ON
Issue #1 - changing / charging batteries that were immersed in miniral oil?

issue #2 - what is keeping the oil out of the focal distance between the light source and the lens? (you don't want lumen absorbing oil in here).
and if this space is an air pocket how much has really been gained filling the rest with oil?
 

gcbryan

Flashlight Enthusiast
Joined
Oct 19, 2009
Messages
2,473
Location
Seattle,WA
The ugly light is working fine thank you.;)

It sounds awfully messy to me as well. I had wondered about the oil between the lens and emitter.

I haven't heard of anyone doing this for a while but it used to be more common. It is probably a good trick to have up your sleeve.

I can't imagine that it ever worked with HID. Maybe it was just in the lower powered Halogen days?

A cheap light filled with mineral oil could save a particular dive I suppose.

Anyway, thanks for the feedback.
 

gallonoffuel

Enlightened
Joined
Mar 11, 2008
Messages
570
Location
Northern MD
Back when people were overclocking their PCs in the original Pentium days, mineral oil was used to completely submerged the motherboard with the theory that the liquid would be a better thermal conductor than air. Interesting to use that concept for dive lighting. I'm fairly confident it wouldn't *hurt* anything, just not sure of its benefit. It might also cause issues with the beam profile.
 

gcbryan

Flashlight Enthusiast
Joined
Oct 19, 2009
Messages
2,473
Location
Seattle,WA
Back when people were overclocking their PCs in the original Pentium days, mineral oil was used to completely submerged the motherboard with the theory that the liquid would be a better thermal conductor than air. Interesting to use that concept for dive lighting. I'm fairly confident it wouldn't *hurt* anything, just not sure of its benefit. It might also cause issues with the beam profile.

The concept for diving isn't about thermal properties but rather about keeping salt water out in the event of a flood.

If it's full of oil...water can't come in.
 

gcbryan

Flashlight Enthusiast
Joined
Oct 19, 2009
Messages
2,473
Location
Seattle,WA
And yet a semi decent dive light would also save the dive and not be messy.

Agreed. Just thinking outside the box a bit. I have no plans concerning mineral oil and dive lights for the foreseeable future!

As an aside...I had a small non-diving light that I converted to a dive light with some silicone sealant. It worked. While I was at it I also used some on the threads. It turned out to be stronger than I thought.

So when the ugly light flooded and after I cleaned it up and fixed the problem based on my experience with the other light I decided to use a little silicone sealant on the bezel thread just as a little extra protection.

It's worked out quite well. Sometimes when you experiment with something in one regard that knowledge is quite helpful later in another regard.

Mineral oil is still an interesting concept (to me) even though I have to plans to use it (as is potting).
 

gallonoffuel

Enlightened
Joined
Mar 11, 2008
Messages
570
Location
Northern MD
The concept for diving isn't about thermal properties but rather about keeping salt water out in the event of a flood.

If it's full of oil...water can't come in.

Understood, just making the point that it shouldn't really hurt anything electrical.
 

gcbryan

Flashlight Enthusiast
Joined
Oct 19, 2009
Messages
2,473
Location
Seattle,WA
Understood, just making the point that it shouldn't really hurt anything electrical.


Sorry, and thanks!

It's interesting that you can spend $600 for a MC-E or P7 dive light, or you can spend $100 for a DX dive light, or you can get a $40 P7 and fill it full of mineral oil and you have an instant dive light!

Hannachan I love reading about your lights and projects but I can't help think that for some of those lights you might as well just fill them with oil.
 

lover018

Newly Enlightened
Joined
Apr 11, 2011
Messages
19
To be honest. I am not a diver but I think distiled water or alcohol could be more usefull and less messy. Just a thought, although I have no backing for my two cents.
EDIT:
On the other hand. I think that water is not a good option cause battery contacts will rust.
Alcohol doesn't make corosion, is lighter than water. And the fishes will like the taste. At least humans do. :)
 
Last edited:

Doc Ed

Newly Enlightened
Joined
Oct 20, 2010
Messages
53
Location
Manila, Philippines
Years ago, I tried this method once with a DIY MR11 based canister light. One problem that developed was that over time, the oil in the light head started to discolor - whether from the heat or from possible salt-water incursion, I can't be certain. Another issue had something to do with my build itself. For some reason, in spite of completely filling the canister with oil, there would later be pockets of air inside (batteries were SLA). At other times I'd surface in a small layer of oil. Overall, it was a messy experiment.
 
Top