Improve Maglite's water resistance

[MetalZone]

Anyone thought about how to improve a maglite's water resistance? I once brought my 2D Mag74 caving in a cave stream... had a bit of water get in and stained my eneloops a little.
I think the most prone areas are the tail caps and front lens.
Could we possibly change the o-rings to thicker ones and use some silicone on the front lens? The switch doesn't look like it's got a good seal either so it could probably use a bit of silicone.

 

[Alex K.]

I don't put my Mags in situations where they could become completely immersed, but I can honestly say that the switch is the weakest link in terms of water resistance. I accidentaly dropped my 3D in the snow last February, and when I clicked it on, the switch started hissing!

 

[Linger]

Yes some o-rings are definately called for. For deeper emersion you'll want a thicker lens but if its just caving a usual hotwire borofloat lens will do nicely.

-A small ring of Norland optical around the bezel and lens could be great. A sufficient o-ring between bezel and would provide access to the reflector after you've sealed in the lens.

o-ring between head and battery tube is helpful, though you could add a band of silicone here for good measure.

Add a tight fitting rubber sleeve over that portion of the battery tube (like a bicycle inner tube).

A rubber sleeve could work well securing the tailcap as well, just ensure you've accounted for the tailcap grooves.

 

[Popsiclestix]

My unbored Mags with borofloat lens survive 30 mins of water immersion in my tub with no signs of water incursion. However, the bored Mags let water in just running it over the tap.

But YMMV.

 

[fivemega]

It is possible to add second groove for double O'ring on body to head, use thicker O'rings on tail cap and bezel but as mentioned earlier, weakest part is switch boot.
Some people used contact cement, others used silicone and some people used epoxy. None of them worked well and they all gave up.

 

[Justin Case]

The constant flexing of the switch boot under use will probably cause any attempt to seal the boot using glues or silicone to fail. I've had reasonable success using a section of rubber bike inner tube over the Mag body. It acts as a giant seal. You can still press the switch boot through the inner tube. The main thing is to make sure that the inner tube doesn't pucker or otherwise open up a gap when you press the switch. That means making sure that the inner tube extends past the switch toward the head to provide sufficient overlap. The inner tube also helps protect the body from dings and provides for a cushioned, insulated grip.

 

[MetalZone]

Thanks for the tips. I'll try to look around for some thicker o-rings.
I'm already using a borofloat lens atm.

My unbored Mags with borofloat lens survive 30 mins of water immersion in my tub with no signs of water incursion. However, the bored Mags let water in just running it over the tap.

But YMMV.

That's odd... My mag has been bored, but I thought boring it only affects the inner diameter of the main body tube and not the o-rings. But it's very clear on my mag that the tailcap o-ring doesn't seal very tightly.

The constant flexing of the switch boot under use will probably cause any attempt to seal the boot using glues or silicone to fail. I've had reasonable success using a section of rubber bike inner tube over the Mag body. It acts as a giant seal. You can still press the switch boot through the inner tube. The main thing is to make sure that the inner tube doesn't pucker or otherwise open up a gap when you press the switch. That means making sure that the inner tube extends past the switch toward the head to provide sufficient overlap. The inner tube also helps protect the body from dings and provides for a cushioned, insulated grip.

Add a tight fitting rubber sleeve over that portion of the battery tube (like a bicycle inner tube).

Interesting. Now I know why some mags I've seen have this rubber thing wrapped around the switch section.

 

[Wetterman]

I've also seen someone put an inner tube on the switch area. It sure is a better seal for water than the original.

 

[mrartillery]

I love my Mags, but if I was put in a situation of possible submersion, they most definitely would not be my first choice. As it has already been stated the boot is your weakest link, my suggestion, get yourself a smaller sealed light with clicky tailcap, that should take all the submersion you can throw at it.

 

[DonShock]

You could try dipping the entire light in Plasti-Dip. Back in my Navy days, I had a Mag2D that was fully coated for electrical safety reasons. A bonus was that the light was very waterproof. I never used it as a divelight, but it was pretty much immune to anything else. I adjusted the head to spot focus prior to coating so the Plasti-Dip was able to stay intact and cover all the joints except the tailcap one. And that o-ring seemed to work fine.

I just dipped the entire light and then cut away the stuff covering the front lens. And then I cut along the tailcap seam so I could remove it for battery changes. The Plasti-Dip works great for sealing the switch. I did a bunch of coats for durability and at first the seal was so good and the dip so stiff that it would take a second for the button to spring back out after turning the light on or off. It was a little disconcerting when turning the light off because there would be a delay until it went off. But it loosened up after a bit and stopped happening.

 

[Popsiclestix]

That's odd... My mag has been bored, but I thought boring it only affects the inner diameter of the main body tube and not the o-rings. But it's very clear on my mag that the tailcap o-ring doesn't seal very tightly.

It seems the sections cut away (they're tri-bores) leave so little material in contact with the O-ring that the tailcap doesn't seal very well.

 

[gcbryan]

The best thing to do would be to not use Mags. If you're not going to dive with them you could use most any clicky switch aluminum light and just add a little marine grade silicone sealant to the edges of the glass lens.

Don't click the light while underwater and don't go too deep or water pressure will do that for you.

You can just buy cheap hand-held backup dive lights. However, if you can buy a cheap light with a twisty type of switch rather than clicky that's even better. You can make something like that dive worthy (to a point) with sealant around the front glass.

If you can find a model with a ledge behind the front lens (like a Surefire 6P or a clone) then with the right o-ring you don't even need sealent. You still have to deal with the tailcap however (for diving purposes).

I don't have any Mags but from what I've seen the big switch on the side is the weak point and is going to be tough to overcome.

 

[fivemega]

My unbored Mags with borofloat lens survive 30 mins of water immersion in my tub with no signs of water incursion. However, the bored Mags let water in just running it over the tap.

That's odd... My mag has been bored, but I thought boring it only affects the inner diameter of the main body tube and not the o-rings. But it's very clear on my mag that the tailcap o-ring doesn't seal very tightly.

Quad boring and all the way boring for bundle of 4AA does not remove much material and will not effect on tail cap O'ring sealing area while tri boring for 3x17mm and dual boring for 2x18mm will remove more material from sealing surface.
Slightly thicker O'ring can solve this problem.

 

[kramer5150]

The switch boot is the weakness. its just a loose fitting rubber piece. There is no clamping mechanics to provide a water pressure seal. Glue and adhesives without clamping mechanics would be risky at best.

I have seen others use plumbers teflon tape around the tailcap and bezel threads. Although this is merely a temporary solution.

 

[rizky_p]

would a few wrap-arounds of sticky tape(celotape) around the switch boot help to waterproof it? It is cheap and temporary solution if it works and the switch might still be usable.

 

[kramer5150]

would a few wrap-arounds of sticky tape(celotape) around the switch boot help to waterproof it? It is cheap and temporary solution if it works and the switch might still be usable.

I am not sure, you would need to check the material properties of the adhesive used on that tape. Its not safe to assume though. I did a google search for "maglite waterproofing", and it came up empty. Surely if the mag could be easily waterproof-modded the DIY dive communities would be all over it.

The only mag-dive conversions I have seen have been canister type designs, that ditch the OEM switch completely. Google search "maglite dive", and you'll see some of them.