Maglite O ring sizes

scubasoulie

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Hi all, totally new to the forum, it's looks full of information to help with my first divelight project.
I've had a bit of a trawl through but can't seem to find O ring upgrading information for maglites. I need to find out all the inner diameter o ring sizes of a D cell maglite and the suggested thicknesses to help waterproof the tailcap and bezel for diving purposes, hope someone can share this info. I'm in UK so metric sizes would be gratefully appreciated. Thanks.
 

jspeybro

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The sizes were mentionned in a post of packhorse on another forum which seem to be offline.
IIRC, the o-rings at the lens should both be 48x2mm, the o-ring in the tailcap 32x2.54mm or something like that (not really sure about that last one). Maybe 350xfire or packhorse can confirm this?
 

Klem

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I use a 2.5mm thick one at the back. Same ID as the factory O ring...Works fine.

I don't use O rings at the front. I use a bead of silicone sealant (Silastic or similar) Rationale being, you only need one access port to the torch for regular battery charging. Any 'servicing' needed on the head/LEDs you can crack the silicone and clean-up the residual flakes with a wire brush reasonably easily. Epoxy putty fixes the lens permanently to the bezel, and silicone to seal the lens to the head (semi permanent).

If it is a wand you are building with no need to regularly open then you could do away with all the O rings. Seal the back up with silicone sealant as well. Up to you, and personal preference.
 
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scubasoulie

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Appreciate the help and quick replies.
I'm actually going to be using the 5 x D cell maglite as a cannister for an umbilical (it'll act as a counter weight for my pony cylinder, lol), the lens is now a solid piece of aluminium with a cable gland in the middle, so I'll probably seal it up permanently shut, just hope I can reach round far enough to access the switch once it's been fully waterproofed. Will let you know how things go.
 

Klem

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Sounds good!

Like the idea of using the Maglite as a canister.

Two quick thoughts;
1. If you're concerned about the location of the canister and effort needed to switch on/off you could shift the switch to your wand.

2. If you're thinking of 'permanently' sealing the canister I take it you will be charging via the wand down the umbilical? In your shoes I'd use at least one O ring on the canister. That way you can easily service/swap the batteries and let the canister air out.

My early experience with sealed battery canisters is that the connections and wiring eventually corrodes (probably due to the trapped humidity condensing after the first dive).
 

Klem

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but not the tail cap ...

I use 32mm (inside diameter) * 2.5mm thick for the tailcaps of D Cell Maglites.

Sourced them on EBay for a few dollars.

I don't have a C Cell so don't know, however if you measure the ID of the factory supplied one and go 2.5mm that will work.
 
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scubasoulie

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Thanks again, I've now got two, 2mm x 48mm ID O-rings and one, 2.5mm x 32mm ID O-ring on order for my D cell mod, coming from a UK supplier at £1.20 each which is quite expensive over here but if it works it will be well worth it.
Just one more question for you, when using a 2.5mm x 32mm o-ring for the tailcap does the o-ring dissappear into the shaft like the original or does it squash between the tailcap and shaft and is still visible from outside when tightened up ? Just wondering as I tried it with a 2.5mm x 34mm ID and you could still see it, maybe just that bit too big. I also had trouble with it earthing without the tailcap touching the shaft but will perhaps take a bit of anodising off the threads if it plays up in future. Thanks.
 

Klem

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2.5mm on the tailcap squashes under the body when you do it up. It's a tight fit but with silicone grease it does up nice and waterproof.

Electrical path is as factory designed.
 

350xfire

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I tried to get a good oring a while back and could not get the proper one. Why not just JB Weld in place and feed wires through cable gland hole?
 

DIWdiver

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I just measured my light, and the tailcap has an OD of 1.000" where the O-ring sits, and the body has 1.125" ID. This is a perfect fit for a -022 size o-ring. Any competent supplier should have them.

I bought a bunch of o-rings at AOP Technologies. They are cheap but have a minimum order. If you only want a few, maybe you want to search on where to buy o-rings. I'm sure there was a discussion about it here somewhere. It's even possible that your local hardware store will have it. It would be specified with "nominal" sizes of: Inner Diameter (ID) = 1", OD = 1-1/8", thickness = 1/16", though the actual spec is ID=0.989", T=0.070".

Since this is such a good fit, and since MAG products are made in the US and would use standard parts wherever possible, I think it's safe to say the light was properly designed with this o-ring in mind, and you will get a very reliable seal at any diving depth with this o-ring in a MAG-C in good condition, provided you properly lubricate and maintain the seal.

Oh, just saw you are in Greece. I don't know if the AS 568A sizes are standard there. If you can't find the correct o-ring or have to pay lots for it, post here and I'm sure someone will help you out.
 

350xfire

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DIW, I think I tried a 22, 23 and 24 and they were all just a bit too big. I think the 22 went in about 1/2 way and would not go in any more. It worked but you do see about 1/2 of it. Not a big issue. I'll look and see as I still have a few laying around. May be some brute force can get it in all the way.
 

DIWdiver

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If a -022 is too big, maybe try a -021?

Edit:
I just found the o-ring that came off my light (I was heating the tailcap with a torch to hot-melt a piezo element into it, so removed the o-ring to avoid burning it). It measures dead on the specs for a -022.
 
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