Zebralight Lens Spontaneously Shattered

I purchased a Zebralight SC50W in early January to replace an iTP A2 as my main bag light. The iTP was rock solid and my first "proper" flashlight, but over time I found the tint to be too cool for my liking. The Z-light has served me very well, and except for the occasional odd moment when it refuses to turn on I've found it to be very reliable.

This light has only ever been used as a bag light. My EDC around the house, backyard, suburbs and generally "doing" things is my Quark AA^2 Tac NW (to be augmented with a NIB Incan Aviator A2-HA with yellow LEDs when it arrives in the next couple of weeks!). Reasonably then, my Quark has a few scratches here and there, but the Z-light is pristine - it lives in a padded section in the middle of my bag. It's very useful for searching for things (in the bag) if I'm at uni or work or if I'm walking home at night.

So I pulled my Z-light out of my bag this evening and saw this:



After recovering from my initial "what on earth; has that really happened?!" paralysis, I tried to work out how it shattered. It hadn't been dropped, and nothing could have bumped the bag hard enough to cause the damage. NOTE: I also had a small netbook, headphones and various other expensive/fragile items in the bag. The bag itself:



...called "The Dreadful Embarrassment", made by a company here in Australia called Cumpler, is my uni/work bag and dosen't get thrown around. The bag is also rainproof and well-padded. Here you can see the pocket it was kept in:



I've marked the pocket with the pink clip (on the left). As you can see it fits the Z-light snugly, and more importantly it's in a padded section in the dead centre of the bag (away from the front/back and the pocket is shallow so it's not near the bottom). In front and below were my scarf and gloves, directly behind was a pocket full of tissues. Behind that was a jumper, a bottle of water and my netbook. Short of being hit by a car I'd have thought it safe.

Has anyone heard of anything like this happening before? I could understand this happening if it was an EDC and I dropped it on the lens, or it was crushed by something heavy, but just to break while stored? What's most puzzling is I don't see how it could have sustained that damage without my netbook breaking; this rules out someone picking up my bag at work today (very unlikely as it's kept in a large drawer under my desk) and dropping it or similar and then not telling me.

To answer some potential questions you might have: (1) I last used it last night when I was walking home, it stayed in the bag on my shelf overnight, took the train to work this morning and it stayed in the bag in a drawer there all day. (2) It's stock standard; no modifications, I'm not doing anything silly like putting lithium cells in it. (3) The "turning off" issue I mentioned before has happened since I bought it. It sometimes just refuses to turn on. This usually goes away if I leave it off for a while. I thought it might be overheating but it does this occasionally from a cold start. It's not battery-related as it does this with batteries at various charge levels. I run Eneloops in it.

Planning to send a message to Zebralight customer service after dinner. Is this the best way to contact them? Are they usually helpful with something like this? Has anyone else ever heard of this happening?

Thanks in advance for any advice/help! (I read CPF a lot though I haven't posted much yet; so I know how knowledgeable you all are) I'll leave you with a couple more pics:

You can see here it's not beat-up:


Front-on: (note the "scratches" around the bezel here are reflections off the shattered glass when my flash fired - you can see that they're not in any of the other pictures)

It looks like it broke right in the centre of the lens, almost like its from internal pressure or a puncture?
Could it have been a heat issue from accidental activation in the bag? Maybe with a pre-existing fault in the lens it could potentially get hot enough to crack the lens...

I want to see it in person, I always liked that light, even if it did feel a little flimsy... (As the guy who got you onto this site, I feel a tiny bit responsible for the pain you now feel :laughing

Cheers,
Alex

That may be, but if it wasn't for you I wouldn't have ANY flashlights so you're remitted of responsibility from now until eternity!

As for overheating, it actually had the battery removed. I'd taken the battery out to charge it last night and noticed I'd forgotten to put it back in this morning. So I grabbed it as I was leaving (the battery that is, the Z-light stayed in my bag overnight) and put it in another section. So it spent the day without a battery in it. Could that be a problem?

Wow that is a strange one, I wonder how it shattered?

Is there actually a hole in the glass where gas could escape, or is it intact apart from the cracks? Does the button switch look as if it could have been distended at some stage? It sounds very unlikely to be a battery issue, but it will help if we can eliminate that possibility.

Most likely, the lens was under stress in some way, perhaps from an unevenness where it was tightened into the bezel. However, a stress from one side would be more likely to cause a diagional crack, not a radial one that appears to have originated at its center.

It will be interesting to hear what ZL say.

~

When they first came out - some lenses were over-sized .......

Which caused them to shatter when the got hot and expanded ......

If I recall correctly .......

So I would return it for a replacement lens.

~

Well if it were lithium batteries I'd guess that the battery vented, but this is an sc50.
Another guess would be that without a battery in it, and oversized glass that the negative pressure from lack of battery in it's compartment it may only take a slight bump for the glass to shatter? I have the sc60 and h30 an there solid lights.
Definitely faulty lens, Zebralight will probably fix it if you send it in. Email em first

To answer some of your questions:

DM51: There is a triangular hole around 2-3mm on each edge. It has its top point in the centre and extends perhaps two-thirds of the radius of the lens. It's very visible in the first photo as the dark section, but it's a hard to see that it's a hole from the photo. The button switch appears normal and has no swelling. The piece of triangular glass I found in the pocket of the bag; it didn't fall inside with the emitter.

TooManyGizmos: This is very interesting...I'll mention it to Z-light. This could certainly cause cracks.

CarpentryHero: Good to hear yours are solid! I've found it to be a very nice light; I like the design, the finish and particularly the interface. It seems extremely solid (compared even with my Quark - it gets a bit of battery rattle). Which is why I was so surprised with what happened today. See point 2 below as it's relevant to your comment.

Some more information that may be useful:

(1) I turned the light on before I noticed the lens was shattered. I got off the bus, instinctively went for the Z-light, and as I picked it up I could feel it was light (ie didn't have a battery in it). While walking I put the battery in and turned it on. Walked all the way home (around 1.5KM) without noticing anything. First bit is on a reasonably busy road; it's actually well lit but hard to see the footpath with oncoming headlights. Was on the higher medium setting (I believe around 36 lumens.) It was then turned off for a couple of minutes as I passed some shops and a petrol (gas) station. Then turned it back on when I neared my street which is darker, so only needed to be on low (4.4 lumens). As I reached my (plain white) front door I noticed the beam was very irregular. I hadn't noticed this earlier as I was walking either on grass or a leaf-covered sidewalk. Once I got inside I had a look a realised why it was irregular. I suspect the lens was shattered when I got off the bus. Previous usage was (as mentioned in original post) around 24 hours earlier.

(2) I've never transported it anywhere without a battery before. Batteries are always swapped immediately when they run out. Today was a special case as my spares had been relocated temporarily to an electronics project and I needed to charge the one in it.

(3) Fellow CPFer ASheep had noticed that it takes a while for the heatsink to get hot, even on max. Compared to my Quark or iTP I've noticed this too - it rarely gets even slightly hot, and if it's on the medium settings it stays cold. Have other people noticed this with Zebralights? Could this suggest it's not heatsinked correctly? I generally don't run this light for long periods.

(4) I've forgotten to lock the tailcap on two occasions and it's come on in my bag. A tap goes straight to max (107 lumens from a XP-E) and it's gotten very warm. Could this thermal expansion weaken the glass? Which could later shatter if it's transported with the battery removed?

(5) The light still functions normally otherwise.


I'll send an overview of what happened to Zebralight. I'll also link them to this post. Is there any other information I should provide?
I'm going to contact through http://www.zebralight.com/crm.asp?action=contactus - is this the correct way to go about it?

Thank you for all your advice! It's very much appreciated.

Interesting, and a good detailed account of how you noticed it. It can't be the cell, as it didn't have one in it (!) - you'd surely have heard or felt something if the lens had cracked while you were walking home.

My guess is TMG has hit on it - if this has happened to ZLs before with tight lenses, this is the likeliest cause here too.

Let us know what ZL say - and good luck!

Quoted below is my message to Zebralight - I'll keep you updated with their reply.

Hi Team,

My Zebralight SC50W lens shattered while in a padded section of my bag. It's a radial fracture from the centre of the lens which has shattered outwards. It has never been dropped or been damaged in any way - so I was very surprised to find it broken when I took it out of my bag.

I've posted the full account and pictures here: http://www.candlepowerforums.com/vb/showthread.php?315721-Zebralight-Lens-Spontaneously-Shattered

Some other CandlePowerForums members have mentioned that there have been occurrences of oversized SC50W lenses shattering in a similar manner.

Considering it hasn't been dropped, I find this spontaneous shattering unacceptable from a company with a reputation for build quality such as yours. Considering the cost, I'd expect it to last more than five months.

What are my options from here? Is this covered under warranty? If you require any additional information please contact me (or alternatively refer to the link above - it has a much more detailed account).

Kind Regards,
James

Australia is the country that is so harsh that it has the top 8/10 deadliest snakes (well anything) in the world. Maybe its could stand the pressure.

We breed them tough down under. Maybe you weeded out the runt of the litter (oh sorry bin seeing we are on CDF) Good luck maybe it was a fluke.

The most likely explanation is that the glass is oversized and unable to take the pressure. There may also be a minor defect in the glass that is the nidus for uneven distribution of force and hence the crack.

pblanch said:

Australia is the country that is so harsh that it has the top 8/10 deadliest snakes (well anything) in the world. Maybe its could stand the pressure.

We breed them tough down under. Maybe you weeded out the runt of the litter (oh sorry bin seeing we are on CDF) Good luck maybe it was a fluke.

Click to expand...

+1 to that, not only snakes, spiders, heck even a kangaroo or koala "drop" bear would try and maul you, more pressure then I could take.

Interesting to hear this happened. I've got a zebralight sc50+ myself...

jhaydon said:

To answer some of your questions:
(1) I turned the light on before I noticed the lens was shattered. I got off the bus, instinctively went for the Z-light, and as I picked it up I could feel it was light (ie didn't have a battery in it). While walking I put the battery in and turned it on. Walked all the way home (around 1.5KM) without noticing anything. First bit is on a reasonably busy road; it's actually well lit but hard to see the footpath with oncoming headlights. Was on the higher medium setting (I believe around 36 lumens.) It was then turned off for a couple of minutes as I passed some shops and a petrol (gas) station. Then turned it back on when I neared my street which is darker, so only needed to be on low (4.4 lumens). As I reached my (plain white) front door I noticed the beam was very irregular. I hadn't noticed this earlier as I was walking either on grass or a leaf-covered sidewalk. Once I got inside I had a look a realised why it was irregular. I suspect the lens was shattered when I got off the bus. Previous usage was (as mentioned in original post) around 24 hours earlier.

Click to expand...

Are you sure you it didn't crack during the usage of the light?

jhaydon said:

(3) Fellow CPFer ASheep had noticed that it takes a while for the heatsink to get hot, even on max. Compared to my Quark or iTP I've noticed this too - it rarely gets even slightly hot, and if it's on the medium settings it stays cold. Have other people noticed this with Zebralights? Could this suggest it's not heatsinked correctly? I generally don't run this light for long periods.

Click to expand...

When using the high mode on nimh my zebralight sc50+ doesn't usually get hot quickly. I have never noticed it get hot on medium or low modes. It does tend to get hotter if I'm using li-ions on the high.

The only thing that makes sense is that the last time you used the light it got warm. You then took out the battery and put it up. The fact that you took the battery out may be the reason this happened, as you left much more air in the tube, that eventually cooled down, created a vacuum, and the lens cracked.

hazna said:

Are you sure you it didn't crack during the usage of the light?

When using the high mode on nimh my zebralight sc50+ doesn't usually get hot quickly. I have never noticed it get hot on medium or low modes. It does tend to get hotter if I'm using li-ions on the high.

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Do you mean "did it maybe crack while I was walking home"? Possibly. I've never had this happen before so I don't know what it would feel or sound like. DM51 seemed to suggest that I'd notice if it happened while I was holding the light. That said, there was lots of traffic noise and I was keeping an eye on the roads I was crossing so if there's no haptic feedback when a lens blows then it's possible I didn't hear it. Does anyone else have an account of a lens shattering during use that's not due to a lithium cell venting (which I'm sure you'd notice)? Even if it did shatter during use I'd still consider this unacceptable as it's the intended use.

As for the heat question I'm very interested to talk to another owner about this. Anyone feel free to correct me if I'm wrong, but wouldn't an XP-E outputting over 100 lumens be generating a reasonable amount of heat? I don't really have a reference to compare it to. My iTP A2 (black aluminium, three mode version) gets quite warm on high very quickly and my Quark AA^2 Tac NW does as well. I know the body of the SC50 is essentially one big heatsink but my experience with heatsinks is that they are meant to be hot (thus, dissipating heat). Is the SC50 just very efficient (either not generating much heat or getting rid of it very quickly)?

Brasso said:

The only thing that makes sense is that the last time you used the light it got warm. You then took out the battery and put it up. The fact that you took the battery out may be the reason this happened, as you left much more air in the tube, that eventually cooled down, created a vacuum, and the lens cracked.

Click to expand...

This makes sense. However the SC50 dosen't seem to ever get very warm. The times it was accidentally left on max were early in its life (2-3 months ago now). That said, could it be heating internally (ie inside the head assembly) during use and I'm not feeling this from the outside, causing the issue you described when the battery was removed?

pblanch said:

Australia is the country that is so harsh that it has the top 8/10 deadliest snakes (well anything) in the world....We breed them tough down under.

Click to expand...

For any non-Aussies planning to travel here, a word of advice; until someone has advised you otherwise, assume that whatever you're dealing with; be it spider, snake, bird, insect, fish, plant, flower, beach, animal, shell or octopus; is going to try and horribly kill you. Because it probably could if it wanted to. Oh, and enjoy your stay!

jhaydon said:

For any non-Aussies planning to travel here, a word of advice; until someone has advised you otherwise, assume that whatever you're dealing with; be it spider, snake, bird, insect, fish, plant, flower, beach, animal, shell or octopus; is going to try and horribly kill you. Because it probably could if it wanted to. Oh, and enjoy your stay!

Click to expand...

Other than those things its a delightful place to visit.

Its smashed from the center. Maybe heat, but can see how without a battery. Has anyone checked out what types of things are covered under warranty, I can imagine this wouldn't be as you didn't have it on. How long have you had it for?

Wow, thats strange. I've dropped my SC51 (bezel first) onto tile and concrete more than a few times and not even a crack. :shrug: