Problem with Arc LS

Ok I can see one reason why the LS lens area isn't water tight. For one, when the battery is screwed onto the head. While twisting the head the air inside is being compressed. With the pressure build up it is being forced out of the lens.
I saw this happen when I tried a feable attempt at waterproofing the lens area with tent sealeant. When I was screwing on the head small bubbles started to come out of the edges on the lens.
Haven't tried to see if the tent sealeant did anything yet.

I don't have a Arc AAA, but how is the lens put on that one?

The 2AA maglight is waterproof because it uses an o-ring. My guess is that even though air pressure builds up inside it is allowed to release throught the ring, yet still provides a good enough seal.

Now I can see why Team ARC is having a hard time trying to seal it properly, due to the way the lens is needed to be seated.

I don't have a Arc AAA, but how is the lens put on that one?



It doesn`t have one, it uses a naked Nichia LED which has the focussing lens moulded into it. the whole head is epoxy potted and is, for all intents and purposes, totally sealed. The only way water gets into the AAAs is through the o-ring seal between the head and body.

I haven't gotten my arc yet, but do you see anyway of modifying the front lens to put an o-ring seal there, much like the minimag? I do have a couple of LS's and it seems like it wouldn't be that hard to incorporate an o-ring seal in the front face of the lens. And you wouldn't need to let the air escape as you're tightenig the battery pack, the extra pressure inside the flashlight should actually improve the water-resistance of the front fact since it is putting more load on the face seal.

Yes, I think this is a flaw in the design of the light. I don't think it is a major one, though, as the implementation of the spring (in the future) will probably minimize the pressure on the head (during screw down).

For the time being, I would only suggest that you tighten the head as little as is necessary for the light to turn on. No need to crank it down...

Perhaps in the future, when modifications are made to the power pack for a tail cap switch (please, Peter!!!), this problem will not be an issue...

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by enlightend:
I haven't gotten my arc yet, but do you see anyway of modifying the front lens to put an o-ring seal there, much like the minimag? I do have a couple of LS's and it seems like it wouldn't be that hard to incorporate an o-ring seal in the front face of the lens. And you wouldn't need to let the air escape as you're tightenig the battery pack, the extra pressure inside the flashlight should actually improve the water-resistance of the front fact since it is putting more load on the face seal.<HR></BLOCKQUOTE>

Unfortunately there is no way to incorporate an o-ring. The lens is epoxied on.

I don't want to retype the whole LS lens waterproofing saga that we went through designing the current model, but we did try many ideas and came to the conclusion the prismatic lens has to go. We had special o-rings made, we tried crimping, special nut and collar assemblies, etc.

I can tell you (since it is obsolete), that the current version uses a plastic collar that crimps the lens against the front face, a metal nut squeezes the collar down. The collar creates a channel between the collar and the metal housing without touching the lens where epoxy is injected. Since the epoxy is thin enough to fill all the nooks and cranies it is also thin enough to wick through the collar joints and foul the lens (anything touching the back of the lens reduces its output because it changes the index of refraction). So we use shoe goop to fill the micro gaps between the collar/lens and collar/nut. Then thin epoxy is injected through holes in the nut to fill the cavity. The fill is designed to flow around the front of the lip of the lens so that is completey sealed. We ruined dozen of lenses and head assemblies before we finally had a version that tested as waterproof. Obiviously, the design didn't transition well to production though.

Many headaches... The new design will use our own lens design so we can include an o-ring friendly lip in it's geometry.

Peter Gransee

Peter,
have you ever thought about going with a separate flat lens kinda like mini-mags? they could fit right over the the optics and prevent them from getting scratched and can be replaced when they get scratched up.

Yes. I don't think the reduction in light output by using two lenses would be noticable. It's a worthwhile trade to get the waterproofing. It is one of the design canidates.

Peter Gransee

Mr. Gransee:

When will the new design be incorporated into the LS light?

Will the LS seconds be available soon again?

I check the order system the other day and the green was available! Came back later to order and it is out of stock..

So who's the culprit who ordered my greenLS

I can tell you that my order (1614) for a white SLS is on hold.