Dark Slayer
Newly Enlightened
Did you try the freezer test??.. Anyone know how he gets the lens out? I can't see why they would epoxy it. I bet it's just screwed on.
TK-75, "Condensation/Fog under lens,again"
- Thread starter Capolini
- Start date
Help Support Candle Power Flashlight Forum
If the head is hermetically sealed and there was water vapor inside, it should condense under the lens anytime the light is taken from ambient temperature to a cold environment, regardless of whether it had been turned on or not. On the other hand, if it took the heat of turbo operation to vaporize whatever it is in the first place, then one would expect that substance to condense and stay under the lens until the head got hot enough to boil it off again... strange. I'm no physicist, but It seems most likely to me that the head isn't truly sealed and moisture can get in and out of it - just not fast enough to avoid condensing on the lens first.
I have a TK75 XM-L2 on the way. I hope I don't encounter this problem. If I do, I'll probably just return the light rather than worry about resolving the issue. As a consumer I don't think that's my job. I agree that a light in this price range shouldn't have condensation problems, especially since Fenix has had plenty of time to address and fix the issue by now. I figured they would have done so with the next generation. Rather disappointing! :ironic:
I have a TK75 XM-L2 on the way. I hope I don't encounter this problem. If I do, I'll probably just return the light rather than worry about resolving the issue. As a consumer I don't think that's my job. I agree that a light in this price range shouldn't have condensation problems, especially since Fenix has had plenty of time to address and fix the issue by now. I figured they would have done so with the next generation. Rather disappointing! :ironic:
It is a strange problem. Yes, my guess would be that the head isn't air tight. So turning on the light will cause the air inside to warm and thus expand. That air (saturated with water vapor or whatever it is) will be forced out of the head. When the light is turned off and the air in the head cools, it will contract and that will cause air from outside to go into the head.
So....
Try putting the light inside a freezer right after turning it off. Air in a freezer doesn't contain much water vapor, due to the low capacity of cold air to hold moisture. That should cause dry air to go into the head, replacing the humid air that escaped.
Do that a few times, and you might dry out the air inside the head.
Probably won't work, but worth a shot. This does seem like a weird problem.
NorthernStar
Enlightened
I second these thoughts! I have intended to buy an old TK75 if i find one to a closeout price, but since this issue with fog under the lens has been reported by so many users i might call of the deal. It would be realy interesting to hear about feedback from the upgraded TK75-L2 if it also suffers from this fog/condensation issue.
It could be an alternative to sending the TK75 to Vinh to get it modified,but that is no solution to the whole issue,and as you said, as a consumer i don´t think that´s my job!
If the issue continues on the upgraded versions of the TK75, i am going to buy a flashlight from another manufacturer instead. The same goes for the RC40 which has been reported to suffer the same condens issue as the TK75, i think that people who had thought about buying the RC40 instead will go for the coming Olight SR96 instead.
There has been many reviews of the TK75 on this forum and from what i have seen none of the reviewers had reported any issue of condens/fog under the lens of their flashlights.The TK75 has been on the market since November 2012. Have they got batches of perfect TK75 or what reason could it be that this issue has not been more spoken about before? Are we talking about isolated batches of TK75 with issues,while others has been good?:thinking:
Capolini
Banned
Thanks for the suggestion but I weighed the Pros and Cons for that about Three weeks ago and decided against it.This is just me! One[1] Pro and Four[4] Cons.
Even if I changed my mind[which I won't] he is not interested in doing my light. I am very open, honest and DIRECT. He was not too pleased with my reasons for going against it!
I know I probably said too much!!
I sent Two lights back. The third was tested[for condensation] before they were to send it to me and it failed the test.
Ciao,,, Roberto,,, "Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
Last edited:
Capolini
Banned
So many thoughts, opinions and suggestions!!
I am going to need to go to TK-75 Therapy after all of this!!
:shrug: :sigh: 
lovecpf
In the end,,,It is all Good!!!
Ciao,,,Roberto,,,"Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
I am going to need to go to TK-75 Therapy after all of this!!
:shrug: :sigh: lovecpfIn the end,,,It is all Good!!!
Ciao,,,Roberto,,,"Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
Dark Slayer
Newly Enlightened
So I keep thinking about this and if someone is modding these they are taking it apart. So monkey see, monkey do.
I take just the head out to the garage and using wood in the jaws clamp it snug with the ring sticking up enough to get a strap wrench on. First try no go. The whole thing started to turn. I had it pretty snug but obviously didn't want to deform it with the vise by over doing it.
I get the heat gun and slowly go around the outside of the ring ring getting it just hot enough that I could still touch it. Maybe 120f if I had to guess. This just enough to let the ring start to turn without the whole head slipping and I got the ring off.
There is a clear plastic washer between the ring and lens and a rubber gasket between the lens and head. It's very humid here right now so I didn't really know what to do now that I had it open and what I could try to use to replace the air inside with. Nitrogen would probably be good but how many of us have that laying around. Or that "air" in a can you blow the dust off camera lenses with. Didn't have that either so I lifted the lens and blew some hot air from the heat gun held about a foot away in there and quickly put the lens back on and tightened it all up.
Stick it in the freezer awhile and still have the same spot as before. No difference what so ever.
More trial and error to come soon. Stay tuned.....
I take just the head out to the garage and using wood in the jaws clamp it snug with the ring sticking up enough to get a strap wrench on. First try no go. The whole thing started to turn. I had it pretty snug but obviously didn't want to deform it with the vise by over doing it.
I get the heat gun and slowly go around the outside of the ring ring getting it just hot enough that I could still touch it. Maybe 120f if I had to guess. This just enough to let the ring start to turn without the whole head slipping and I got the ring off.
There is a clear plastic washer between the ring and lens and a rubber gasket between the lens and head. It's very humid here right now so I didn't really know what to do now that I had it open and what I could try to use to replace the air inside with. Nitrogen would probably be good but how many of us have that laying around. Or that "air" in a can you blow the dust off camera lenses with. Didn't have that either so I lifted the lens and blew some hot air from the heat gun held about a foot away in there and quickly put the lens back on and tightened it all up.
Stick it in the freezer awhile and still have the same spot as before. No difference what so ever.
More trial and error to come soon. Stay tuned.....
Capolini
Banned
Hope you don't ruin your torch! I see some serious condensation problems on the horizon! It is also very humid here in suburban Philly!
Ciao,,,Roberto,,,"Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
Last edited:
I don't think that will remove any humidity. Heating air will reduce its relative humidity, but absolute humidity still remains the same. i.e., that hot air still contains the same amount of water vapor. When that hot air inside the light cools down again, it's relative humidity will be the same as the regular house air you previously heated.
The only thing blowing hot air might do is evaporate any liquid water inside the head, and get rid of it that way. But using hot air or regular air after that won't make any difference. You should close it up when in an air-conditioned room with low humidity.
Anyway, I don't think we're 100% sure that the fogging is the result of water.
Dark Slayer
Newly Enlightened
After blowing the hot air into it I ran it on turbo in front of the fan and there was NO fog spot. Ran it in the freezer on turbo and same spot as originally. Put it back in front of the fan on turbo and after six mins spot was around 60% gone. Turned fan off and within two mins spot was gone (still on turbo).
Have to go put door knobs on at mothers. More to come..... Wonder if propane has moisture in it, hmmm.
Have to go put door knobs on at mothers. More to come..... Wonder if propane has moisture in it, hmmm.
Capolini
Banned
I have a suggestion!! Use it in NORMAL circumstances like me!!! No fans involved, just using it naturally.Take a walk for an hour and run it on CONTINUOUS TURBO, disregarding step downs, putting it right back to turbo.Check it every couple of minutes WITHOUT turning it off or at a lower mode. I am sure you could figure it out, but I will tell you anyway!! Put the light on an angle when you check for condensation so you don't BLIND yourself!
Please do this one day/night and let me know what the results are?
Ciao,,, Roberto,,"Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
P.S. I was born in Cleveland!! Also,I am 53 years old and average 6 miles of walking a day with the Siberian!! I am sure you are younger and can walk 3 or 4 miles for the TK-75 Natural Turbo Condensation Test!!
:huh: :thumbsup:
Tenebrae
Newly Enlightened
- Joined
- Oct 1, 2011
- Messages
- 23
Hmm...would you describe him as a prima donna, Roberto? If so, I might have to reconsider my future modding plans.
Of course each person is free to do as they see fit regarding this problem, but I consider this a zero tolerance issue - either the thing works as it's supposed to or it doesn't... period. The design is clearly defective or the QC is inadequate if this is happening with any kind of frequency. It ought to be Fenix's job to correct the problem, not the customers. Instead of subsidizing Fenix and fixing their lemons for them, I suggest sending the thing back and demanding your money back if you're not completely satisfied. None of my other lights do this, and I'm hoping this one won't either, but if it does - back it goes! I see no excuses here for Fenix (or the vendors that sell it). Get it right or get it off the market!
Dark Slayer
Newly Enlightened
I'm 53 also and retired. I do take walks and have woods/fields above me. Also my front door is 42' from a river bank and I always spot for fish, raccoons and there is even a muskrat that is always going past.I have a suggestion!! Use it in NORMAL circumstances like me!!! No fans involved, just using it naturally.Take a walk for an hour and run it on CONTINUOUS TURBO, disregarding step downs, putting it right back to turbo.Check it every couple of minutes WITHOUT turning it off or at a lower mode. I am sure you could figure it out, but I will tell you anyway!! Put the light on an angle when you check for condensation so you don't BLIND yourself!
Please do this one day/night and let me know what the results are?
Ciao,,, Roberto,,"Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
P.S. I was born in Cleveland!! Also,I am 53 years old and average 6 miles of walking a day with the Siberian!! I am sure you are younger and can walk 3 or 4 miles for the TK-75 Natural Turbo Condensation Test!!
Anyway I did state before that so far mine has never fogged during actual use even when ran hard and hot and out here I usually do. Thats why I got the lights that I did. Only when testing (run times and such) with a fan and that keeps the lens cooler that normal while running.
It did seem to help at least on turbo with fan because no spot show this time and it did before I took it apart. So I'm getting somewhere. I think I'll try the air conditioner thing before trying to replace the air with some other gas.
If I suddenly stop posting then the propane didn't work.
Last edited:
thedoc007
Flashlight Enthusiast
Taken from a cell phone repair forum, this is not my work:
http://www.droidforums.net/forum/droid-faq/8539-how-deal-droid-thats-gotten-wet-right-way-4.html
But, the same speed of water removal can be achieved much more safely by using distilled water for a rinse and silica desiccant for moisture removal. In your research you should have found that silica desiccant will absorb ~40% of it's weight in water from the air. A large volume of desiccant in a small, sealed, container will remove small quantities of water VERY rapidly. Try this little experiment: get a ~10oz container of silica desiccant and put it in a sealed container such as a large ziplock bag along with a 2oz shotglass of water. In less than 24 hours the shotglass will be empty and bone dry. No cell phone can hold 2oz of water after any reasonable effort to drain it, likely less than 1/8oz. Even water in tight spaces will evaporate quickly as the humidity in the container plummets and all available moisture wicked into the air and then into the desiccant.
I'm unclear on why some don't trust desiccants as they are used in almost any industry where moisture control and removal is key. Their moisture removal properties are measureable and consistent to the point that the exact weight of the little packets in food, pharmaceutical and agricultural items is carefully selected to maintain a precise moisture level in the product. They are used to help dry paint in very humid climates in an entire room (Home Depot actually merchandises them in the paint department). I have used this method on 2 of my own phones (an SCH a670 survived a full wash cycle in the washing machine, lol), my ex's grandmother's phone, one of my employee's phone and a laptop (glass of water dumped right into the keyboard while powered off, broke me of leaving the laptop on the kitchen counter though) over the last 5 years or so. I have used desiccants for the last 15 years to dry 10-15lbs of peppers every fall as well as many other odds and ends that needed drying. The most readily available, reliable, brand I have found is DampRid and you can get it at most hardware stores and even wal mart (on the laundry supply isle with irons and hangers, sold to put in the closet to keep clothes from mildewing in damp climates). Drierite is another readily available brand but it is not silica based, it is calcium sulfate. Technically it is a better desiccant in that it can absorb more water per unit weight but the thing I don't like about it is that as it absorbs water close to it's maximum it starts to clump together and makes it hard to re-use. Both can be recharged by baking at about 250 degrees for a few hours but once the drierite has clumped together it's surface area is greatly reduced and it is not as effective.
In my experience, fresh desiccant can dry the average phone in less than 12 hours if done properly. Buy a 10+oz container of silica desiccant, place it and the phone in the smallest possible air tight container and leave it overnight. If the desiccant isn't freshly purchased and still sealed, recharge it first. The little packets in your shoe boxes, pill bottles, and beef jerky bags are already saturated, they wont do you much good unless you recharge them first.
And just as a side note, rice is not a hoax. It is not nearly as effective as silica gel or calcium sulfate but it will dry faster than leaving something in open air. Try another experiment: place a 1oz shotglass of water in a ziplock bag with about 2 cups of rice and place a second 1 oz shotglass of water on the counter next to it and see which one evaporates fastest. Try it and see for yourself.
I have tried it, in real world use, after dunking my cell phone in a river for several minutes. I put in in the sun for a few minutes on site, then packed it up, and put it in a bag of rice as soon as I got home. It had visible water behind the screen when I put it in the bag, and the next morning (about 10 hours later) it looked totally fine and fired up without any problems, have been using it for months now with no issues.
If you had said "there are better options available", I would agree. But calling it a hoax, and particularly stating that "it only draws moisture from a surface it is in direct contact with" is indeed flat wrong. Rather than stating an absolute, and not explaining why, next time please do some checking first. Again, it may not be the best option, but if a bag of rice is all you have, it works, and it is a lot better than just letting it air dry.
Capolini
Banned
I Wouldn't say that! He has a good reputation. It was my decision. I asked him about 20 questions and he took the time to answer them! He just didn't like when I told him that the only "Pro" was the light would be more powerful! You have to consider loss of warranty, cost, light gets hotter, run time diminishes, ect.
Ciao,,, Roberto "Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
Capolini
Banned
UPDATE
I see a progression here in a POSITIVE direction. I am hopeful, but I am not getting my hopes up!
I have used the replacement TK-75 Three times on continuous TURBO for 62 minutes.
First time: Condensation[?] began forming in 12 minutes.
Second time: " " " " " " " " " " 25 minutes.
Third time: " " " " " " " " " 38 minutes.
If that pattern continues for a half dozen or more times, The mystery blob won't even be an issue when I use my battery kit ext. when the weather gets cooler and colder and my hikes increase in time w/ the Husky! :thumbsup:
Another interesting observation. I examined the "Condensation like material" with a magnifying glass. A little smaller than a quarter and is oval shaped. I looked at it for about 3 or 4 minutes. It was actually dissipating a bit as I was doing this.
The best way I can describe it is, it looked like a thousand microdots. My Scientific guess is that is looks more like some "Chemical reaction" than any form of H2o. Hopefully I can get some other opinions on it. Teej lives an hour away, we may get together and he could become the Scientist!! :thinking:
Ciao,,,Roberto,,, "Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
I see a progression here in a POSITIVE direction. I am hopeful, but I am not getting my hopes up!
I have used the replacement TK-75 Three times on continuous TURBO for 62 minutes.
First time: Condensation[?] began forming in 12 minutes.
Second time: " " " " " " " " " " 25 minutes.
Third time: " " " " " " " " " 38 minutes.
If that pattern continues for a half dozen or more times, The mystery blob won't even be an issue when I use my battery kit ext. when the weather gets cooler and colder and my hikes increase in time w/ the Husky! :thumbsup:
Another interesting observation. I examined the "Condensation like material" with a magnifying glass. A little smaller than a quarter and is oval shaped. I looked at it for about 3 or 4 minutes. It was actually dissipating a bit as I was doing this.
The best way I can describe it is, it looked like a thousand microdots. My Scientific guess is that is looks more like some "Chemical reaction" than any form of H2o. Hopefully I can get some other opinions on it. Teej lives an hour away, we may get together and he could become the Scientist!! :thinking:
Ciao,,,Roberto,,, "Capo di Capo" "KEEP LIGHTING UP THE DARKNESS"
Last edited:
Tenebrae
Newly Enlightened
- Joined
- Oct 1, 2011
- Messages
- 23
Good to hear, Roberto! Thanks for the update and for the earlier assessment. Very helpful!
Dark Slayer
Newly Enlightened
This time I let a dehumidifier blow air into it. A digital gauge showed 41% and dropping.
Into the freezer (light off) it goes. 20mins later when removed spot is there but it went away within a minute.
Same test in the fridge with light off, NO spot. Before disassembly it did form a spot.
Same test in the fridge with light on turbo, kidney shaped spot roughly centered.
But on turbo with fan NO spot or spots. About the same result as blowing heated air into it. Before removing lens it would get small spots just above the leds.
So it has seemed to help some.
Improvment:
In fridge, light off, no spot formed.
On turbo, tail standing with fan running, no spot formed.
No improvment:
Freezer light on or off.
Fridge light on.
Will have to wait till I get some nice cool nights and see what she does outside then. Thankfully I've had
no problems in actual use, so far.
Can't believe there isn't a ton of 75 users or some of the well known reviewers chiming in.
I also noticed that somewhere in the 3.8 ish cell volt range when turning it off when on turbo mine will default to high instead of turbo when I turn it back on. Kind of a little nudge to let you know you aren't there but your getting there.
Into the freezer (light off) it goes. 20mins later when removed spot is there but it went away within a minute.
Same test in the fridge with light off, NO spot. Before disassembly it did form a spot.
Same test in the fridge with light on turbo, kidney shaped spot roughly centered.
But on turbo with fan NO spot or spots. About the same result as blowing heated air into it. Before removing lens it would get small spots just above the leds.
So it has seemed to help some.
Improvment:
In fridge, light off, no spot formed.
On turbo, tail standing with fan running, no spot formed.
No improvment:
Freezer light on or off.
Fridge light on.
Will have to wait till I get some nice cool nights and see what she does outside then. Thankfully I've had
no problems in actual use, so far.
Can't believe there isn't a ton of 75 users or some of the well known reviewers chiming in.
I also noticed that somewhere in the 3.8 ish cell volt range when turning it off when on turbo mine will default to high instead of turbo when I turn it back on. Kind of a little nudge to let you know you aren't there but your getting there.
I received my new TK75 XM-L2 yesterday. After reading all these posts I was under the impression that this light has major problems beyond other flashlights in regard to moisture and condensation. So, today I placed it and my Olight SR-51, Thrunite TN31, 4 Sevens Maelstrom S-10, Jetbeam RRT-3, Eagletac TX25C2 and Nitecore SRT-7 in the freezer with the heads up for about 7 minutes or so. None of them had been turned on previously and all of them had been bought new and never disassembled. To my surprise, upon removal, every single one of them had some degree of condensation inside the lens. The TK75 had the largest spot, but then again it has the largest head and presumably the greatest volume of air inside.
From the above it seems to me that this is a much more common occurrence than many of you might think and either (1) no manufacturer purges the moisture out of the heads before sealing, (2) the flashlights may not really be as impermeable to moisture as advertised, or (3) both.
I don't see why turning the flashlight on or off beforehand should make any difference (provided we're talking about water vapor and not some other rather unlikely exotic compound), except that a warm lens will take longer to get cold enough to condense moisture on it than an already cool one. The same principal is used in objective lens heaters for telescopes in astronomy.
I was all set to send my new light back if I encountered this issue, but now I've reconsidered, since several of my other lights do the same thing when tested and I've never had problems with them in actual real world use, even in winter in Wisconsin. For those who use their lights in truly extreme environments (like walk-in deep freezer meat inspectors), maybe this is a deal breaker, but for rest of us I don't see why it should hinder the use of this otherwise very impressive flashlight.
Try the simple experiment above with some of the your other lights and see what you find.
From the above it seems to me that this is a much more common occurrence than many of you might think and either (1) no manufacturer purges the moisture out of the heads before sealing, (2) the flashlights may not really be as impermeable to moisture as advertised, or (3) both.
I don't see why turning the flashlight on or off beforehand should make any difference (provided we're talking about water vapor and not some other rather unlikely exotic compound), except that a warm lens will take longer to get cold enough to condense moisture on it than an already cool one. The same principal is used in objective lens heaters for telescopes in astronomy.
I was all set to send my new light back if I encountered this issue, but now I've reconsidered, since several of my other lights do the same thing when tested and I've never had problems with them in actual real world use, even in winter in Wisconsin. For those who use their lights in truly extreme environments (like walk-in deep freezer meat inspectors), maybe this is a deal breaker, but for rest of us I don't see why it should hinder the use of this otherwise very impressive flashlight.
Try the simple experiment above with some of the your other lights and see what you find.
Last edited:
