Let me preface by saying that I really like my EX10. Conceptually it's my favorite light. In terms of build quality, it's my favorite light.
However, it came with a host of (resolvable) problems.
1. Operation of the switch.
The switch was stiff, hard to press, and the return was so slow as to make double-tapping VERY difficult, and impossible after storing the light for awhile. Cleaning the o-ring (clear) and replacing the lubrication with a teflon-based lube did not help nearly as much as I thought it would.
1.1 The solution to this problem was in the box all along. The EX10 came with 2 spare O-rings, one red, and one clear. Now the O-ring that was on the PD cylinder was also clear, but when examined next to the red O-ring, the one that was installed by default was MUCH thicker (1.5X at least). Replacing the clear o-ring with the red one and using some teflon-based lubricant resolved the issue beautifully.
2. Water-resistance.
I tested EX10s water resistance by dunking it into a pot of water, and using the switch 1-2 times under water. The light did function without a problem. But a few minutes after it was retrieved from the water, a thick fog covered the lens, and it was clear that water had gotten inside. The battery chamber was dry, so it was clear that the problem lie with the emitter compartment.
I disassembled the light, to find out that the reason for the water getting in was inherent in the design. In most lights, the reflector rests on an o-ring against the lip of the casing, with the reflector screwed behind it, squeezing the o-ring between the lens and the lip of the casing, and thus providing an excellent seal.
In the EX10, the O-ring is instead positioned between the reflector and the glass, resting partially in the threading, with no lip to rest against. In essence, the water is free to flow AROUND the seal at any time when the pressure changes (such as when using the switch).
In the subsequent editions of the EX10, I would highly recommend that the Nitecore design team take care of this engineering flaw, because even with my haphazard solution (below) implemented, the problem is greatly lessened, but it's clear the light would not withstand any real submersion.
2.1 For me, the solution was to lube the o-ring with thick silicone-based grease... use forceps to carefully position it into the groove of the threading, and then take great care not to dislodge it when screwing the cap down. I also added some vaccuum grease between the bezel ring and the glass (there should be a flat rubber gasket between those two, by the way!), and used the clear o-ring that I had taken off the PD cylinder between the outside of the steel bezel ring. When the bezel was fully screwed on, this o-ring provides a very decent seal to further help avoid water getting into the head of the light.
After these modifications, the light successfully withstood immersion and operation in 10cm of water... but it is unlikely to take anything more than that.
In conclusion, I'd like to thank David and the Nitecore team for a wonderful light. Despite its shortcomings it's become my EDC, and I am anxious to see the problems corrected, at which point I will purchase the new version and pass my EX10 to someone else.
However, it came with a host of (resolvable) problems.
1. Operation of the switch.
The switch was stiff, hard to press, and the return was so slow as to make double-tapping VERY difficult, and impossible after storing the light for awhile. Cleaning the o-ring (clear) and replacing the lubrication with a teflon-based lube did not help nearly as much as I thought it would.
1.1 The solution to this problem was in the box all along. The EX10 came with 2 spare O-rings, one red, and one clear. Now the O-ring that was on the PD cylinder was also clear, but when examined next to the red O-ring, the one that was installed by default was MUCH thicker (1.5X at least). Replacing the clear o-ring with the red one and using some teflon-based lubricant resolved the issue beautifully.
2. Water-resistance.
I tested EX10s water resistance by dunking it into a pot of water, and using the switch 1-2 times under water. The light did function without a problem. But a few minutes after it was retrieved from the water, a thick fog covered the lens, and it was clear that water had gotten inside. The battery chamber was dry, so it was clear that the problem lie with the emitter compartment.
I disassembled the light, to find out that the reason for the water getting in was inherent in the design. In most lights, the reflector rests on an o-ring against the lip of the casing, with the reflector screwed behind it, squeezing the o-ring between the lens and the lip of the casing, and thus providing an excellent seal.
In the EX10, the O-ring is instead positioned between the reflector and the glass, resting partially in the threading, with no lip to rest against. In essence, the water is free to flow AROUND the seal at any time when the pressure changes (such as when using the switch).
In the subsequent editions of the EX10, I would highly recommend that the Nitecore design team take care of this engineering flaw, because even with my haphazard solution (below) implemented, the problem is greatly lessened, but it's clear the light would not withstand any real submersion.
2.1 For me, the solution was to lube the o-ring with thick silicone-based grease... use forceps to carefully position it into the groove of the threading, and then take great care not to dislodge it when screwing the cap down. I also added some vaccuum grease between the bezel ring and the glass (there should be a flat rubber gasket between those two, by the way!), and used the clear o-ring that I had taken off the PD cylinder between the outside of the steel bezel ring. When the bezel was fully screwed on, this o-ring provides a very decent seal to further help avoid water getting into the head of the light.
After these modifications, the light successfully withstood immersion and operation in 10cm of water... but it is unlikely to take anything more than that.
In conclusion, I'd like to thank David and the Nitecore team for a wonderful light. Despite its shortcomings it's become my EDC, and I am anxious to see the problems corrected, at which point I will purchase the new version and pass my EX10 to someone else.
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