Fenix TK40 Review - NEW beamshots up

Wattnot

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REVIEW: Fenix TK40

Hi All and welcome to another review on a great new light. The Fenix TK40 needs no introduction as it seems to have taken this site by storm. The bar has been moved up quite a bit on output and features. The most notable difference is the battery system (4 or 8 AAs) and we'll talk about that at length. This Fenix TK40 was provided by PTS Flashlights (shameless plug!).


Manufacturer's features and specifications (from PTS's site):

Specifications

Model
Fenix TK40

Housing Material
Aircraft Grade Aluminum

Output Power
Up to 630 lumen

Lamp assembly
Cree MC-E Quad Super LED

Reflector
Light Orange-Peel

Battery type
8 AA (alkaline, NiMh or AA-Lithium primary)

Finish
Black Type III Hard Anodized

Water Proof
Waterproof to IPX-8 Standards



IMG_0087_1.jpg


Initial Impressions:

Sliding the ornate paper sleeve reveals a plastic storage/carrying case. I won't slam this too hard because I've already read where Fenix owned up to the mediocre design and I believe a better built case will be along shortly, if not already. It's not that bad, however. The biggest problem I see with it is that it doesn't close completely around the seam. Inside the snug case (besides the light, of course) is a bag with extra O-rings, rubber switch cover and a lanyard. I'm not sure who's going to use this but there is also a giant shoulder strap. I'm not even going to comment on that!

IMG_0088.jpg

From left to right - TK40, Wolf Eyes Sniper P7, Surefire A2

The light is big. It's roughly the size of an M6 but with a smaller head and slightly thinner body. Speaking of thin, it certainly feels thin and light for it's size without the batteries installed. I'm a little concerned about it's ability to withstand "professional" abuse but only time will tell. I wouldn't suggest a cop try and carry this light on a duty belt but it would certainly be a great light to be carried in a "trunk" bag while on patrol. Don't get me wrong . . . this is a first impression and I'm not saying this light is a "wimp." I was just a little surprised that it wasn't a little thicker, due to it's size. I get the feeling that dropping this on a concrete floor from 6 or more feet up is "gonna leave a mark," that's all. Sorry, I'm NOT going to try it!


IMG_0096.jpg

Here you can see what I'm talking about where the thickness is concerned - 3D Mag on right.

The TK40 has a forward computer controlling "clicky" and is HAIII hard anodized and has non-aggressive knurling. It weighs 10.0 oz empty and 17.2 ounces with 8 nimh batteries. The fit and finish and threads are all great. In fact, the best I've seen on any Fenix. As I'm sure you've heard, the output is simply . . . . WOW. VERY impressive output, especially for it's size (I know, I say that a lot!). This light can't top my Mag 85 but I believe it tied or even edged out my ROP (but with a larger hotspot and much less spill). In any event, the folks who joust in the "INCAN VS. LED war" threads have a new lance with this puppy.

IMG_0094.jpg


IMG_0089.jpg

TK40 on left - WE Sniper P7 right

UI:

Oh boy . . . the UI is a doozy. It takes a little getting used to and even then I'm sure not everyone will like it, but it does remember the last level so that will be some solace for the folks who like simplicity. I normally do NOT like that feature (it's why I don't own any Olights) but on the TK40, it is most welcomed.

Okay so here goes: A single click turns it on. Like I said, it comes on in the last mode used so that will put it in 1 of 4 output levels. AFTER it's on, and you've released the button, you press and hold and in short order you get the next level. Not too bad so far. If you want to explore the extra features (warning, strobe/sos haters need to turn to another station NOW) you double tap. The extra modes appear to be tied in to certain light levels, which is true of other Fenix lights. The chosen intensities do make sense so it's not that bad but it takes a while to move around the modes to find what you want. On it's lowest setting, double tapping gets you a beacon (a double tap gets you out of the special mode where a single tap just shuts it off). The next level up gives you SOS. The timing is a little faster and tighter than the P2D/P3D/LOD timing but it's still not perfect. One oddity I noticed on the SOS: On my light (check this on yours) the second and third "O" (the long duration "dashes" between the short "dots") have a slight blip of a higher intensity. It's noticeable but not too distracting (but "Joe" noticed it right away – that will make sense later). Level three's double tap gives you a slow strobe and Turbo's double tap gives you a very fast strobe. I suppose this light can be used in a stress/tactical operation but you had better practice with it a lot and not mess with any other light with computer based UI. If you left it on high the last time you used it, turning it on followed by a double tap will get you your strobe. Mess that up at all and you'll be lost and the would be strobe-ee will own you. I tried "triple tapping" it from off for the purpose of getting it to strobe immediately but that did NOT work. It needed a little pause after turning it on before the double tap put it in strobe mode.

Logistics:

There is no clip so you're either going to need to find a big holster or go with the lanyard. Of course you can whip out the shoulder harness for maximum nerd prowess but I don't recommend it. The body diameter is nearly identical to a D Mag so most D-sized Mag holster products should work. The TK40 can easily tailstand with good stability. There is one O-ring on each end. The reflector is deep, highly polished and has a light OP finish. The LED is well centered. The knurling is mostly for looks as it's fairly smooth. However, the light doesn't seem too slippery . . . the sheer size of it should keep it from slipping out of your hand anyway. The battery system was very well designed and I like it a lot (expect for a little rattling – Fenix, you need to fix that please). I would hope to see extra battery holders available but keeping them loaded will prove to be a challenge as there is nothing preventing the batteries from popping right out of the holder when not in the light. If Fenix offers extra battery holders for sale, I strongly suggest they design a little sleeve that could be left on all the time, or perhaps just slide it off right before installation. Hey Fenix, maybe you could take care of both problems if the sleeve is thick enough to stop the rattle. Now here's the really cool part about this battery system: The TK40 can accept four or eight AA batteries. Just load two of the four slots, making sure you choose two opposite directions in adjoining slots. It is possible to mistakenly use two adjoining columns where all 4 point in the same direction. Nay nay on that – you have to choose one from column A (pointing up) and one from column B (pointing down). After that, you're golden. Very well done, Fenix. There are "dots" on the battery tube to guide you on the 4 battery mode but I never saw them until I knew about them (I never read instructions . . . at first). With 4 batteries installed, the light comes on in all it's glory and all it's modes just like there are 8 batteries in there, but Fenix recommends not using turbo with 4 batteries for fear you may damage the cells. I know there have been some negative comments floating around about Fenixes decision to use AAs. I'll give my opinion on that in the conclusion but the unique ability to use 4 instead of 8 should quell at least some of those types of concerns.

Current draw:

This was a little challenging. Somebody owes me something for this. Send me your tired old Ti light or something. What a pain. I had alligator clips, home brew insulated rods and a jumble of wires all over the place. All to find out it's probably doing what everyone expected! First, a note on my AA nimh battery situation. I have 8 older Maha 1600ma Powerex batteries. They've seen little use and still read 1.4 on a full charge but they're several years old. I also have 4 new Eneloops. My apologies for not being fully prepared. The light came unexpected. I'm working on several reviews right now and I was not expecting this one to arrive first. Dock my pay, what can I say ;). So with that being said, here are some measurements, which were virtually identical with 4 Eneloops or 8 Mahas.

Lo: 25ma
Medium: 250 ma
Hi: 700 to 800ma
Turbo 2.6 amps

When measuring turbo, the meter slowly climbed up as high as 3 amps right away, then settled back down to a solid 2.6A. I've used this meter in all of my reviews and never saw it climb like that. It didn't stay there but went back down to 2.6. It did this with both the Powerexes and the Eneloops. Parasitic drain: Yes Virginia, there is a parasite in there and it's sipping a constant .38ma (that's point three eight, under 1 ma) from the batteries. I had no way of measuring this with the tailcap on so if the battery is making contact with the contacts under the head, it will draw.38ma. The only way unscrewing the tailcap is going to stop this drain is if you turn it out enough to break the contact AND TAILSTAND THE LIGHT. The springs on both the negative and positive have a long reach so you're going to have to unscrew the tailcap to the point where it almost falls off.


In the hands of "babes:"

I did this on my last review. I took a little walk over to my "non-flashaholic" neighbor's house. Lets call him "Joe." Okay, that's great because his name really is Joe. He's a mechanic but to him a good flashlight is (or was) a stock Mag. I'm slowly converting him but there is no "passion" there. This makes him a great subject to hand a light to for an opinion. His first impression was positive. Joe liked the look and feel of the light but agreed with me on the thin-ness of the tube wall AFTER I removed the batteries. He was completely lost with the UI. I had to instruct him all the way. Pressing and holding made sense to him but with the TK40 you have to first turn it on, let the button go, THEN press and hold. Joe and I both agree that pressing and holding from being on OR OFF would have been a more intuitive design. The instructions on switching through the levels are not perfectly clear on the light needing to be ON first.

The beam and white walling:

Fenix gets very high marks for the beam. I don't know how they did it but once I got it more than 18 inches from the wall I could NOT tell it was a quad core emitter. I saw no rings or dark spots. I made a crack about a Phillips head screw slot in this thread about this beamshot but that disappears completely, never to return, once you're more than 2 feet from the wall. The hotspot is also HUGE and the spill is very good.


PWM

Using my highly scientific test method (pointing it into a fan) I discovered no PWM on ANY power level. Either it's using another dimming technology or I need a faster fan. Maybe I can go to the airport and stand in front of a turboprop and see if that reveals some super high frequency my house fan won't show!

Conclusions:

There's a lot of competition out there. There's Tiablo, Jetbeam, Eagletac and others all pumping out some very impressive powerhouses as of late. Too bad Surefire decided just to make brochures instead of lights (oops, did I type that out loud?) because these guys are having a ball out here in the real world. So I'm thinking Fenix wanted to do something a little different and that's why we have the 8 AA setup. I'm sure the AA's are meant to appeal to the general public. The light is a little bigger than it needs to be and that is because of the battery tube. But the general public knows what Maglite is and to the layman, that IS a "flashlight." The TK40 fits the hand nicely and for someone who grew up on Maglite, this will probably appeal to them more than the 18650 lights. I've read the arguments for and against using AAs and I feel this is just different, that's all. It's diverse. However, if the general public is the target Fenix wants, I'm surprised they didn't go with a thumb switch on the body and a simpler UI. If it were me in that design room, I would have pushed for those features.

Beamshots:

NOTE about the following beamshots: For those of you looking at my older reviews, my house was painted and the color is slightly darker. The incan skews it one way and the LED the other. The real color is between the two but MUCH more accurate with the ROP. Also, to allow the P7 to show up properly, the ROP and TK40 seem a tad overexposed. However, the exposure was set the same for each distance each time.

IMG_0109.jpg

ROP 100 feet


IMG_0110.jpg

TK40 100 feet


IMG_0111.jpg

Wolf Eyes P7 Sniper 100 feet


IMG_0112.jpg

ROP 150 feet


IMG_0113.jpg

TK40 150 feet


IMG_0114.jpg

P7 Sniper 150 feet


IMG_0116.jpg

ROP 200 feet


IMG_0117.jpg

TK40 200 feet


IMG_0118.jpg

P7 Sniper 200 feet


IMG_0119.jpg

ROP 300 feet


IMG_0121.jpg

TK40 300 feet


IMG_0122.jpg

P7 Sniper 300 feet (I didn't think this would even show but not bad!)


Conclusions (continued):

So I say BUY IT! Hmmmm . . . I guess I should start some sort of rating system. What do you think? A 5 star scale or a 10 point scale? My 10 point scales always end up as 20 points (or at lest 15) because I always find myself saying "7.5." In fact, lets just go with that . . . overall I give it a 7.5. The output is great and if that were the only criteria, it would be a 10. The 4 or 8 battery system works well and I'd give that a 9. The fit and finish gets a 9. The UI gets a 6 because it is not intuitive on a light that's trying to appeal to a broad audience. When I left poor Joe, he was twitching and mumbling incoherently and I know it was because of the UI. I only gave the UI a 6 because I personally don't mind complexity in my gadgets. Had I been a general "all product reviewer" who was not a Flashaholic, I would have probably given it a 3 or 4 (but of course once I was used to it, that number would rise). It has all of the loved (and hated) "bells and whistles" so for features I'll give it a 9. I'm concerned about it's durability in rough service (so I'll give durability a 7) but that may just be my perception based on the way it feels. It very well may stand up just fine but if you were set up a cage match to the death by filling a clothes dryer with M6s and TK40s, my money will go on the M6s.

There are many fine retailers for this light but I recommend www.PTS-Flashlights.com for great prices and great service. CPF members who set up an account receive special pricing on everything they sell.


I hope you enjoyed this review.
 
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adirondackdestroyer

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Re: Fenix TK40 Review

Nice review! :thumbsup:

It looks like a nice light, but I really wish it didn't use a battery adapter, and didn't have a parasitic drain. It looks like a great light other than those two downfalls.
 

shuter

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Re: Fenix TK40 Review

Thanks for the review Wattnot. I think you nailed it. The thinness of the tube has me wondering about durability but perhaps they are using a tougher quality aluminum than the MagLite. The user interface sequence is not intuitive. It could be easier. Most of all, I wish they had used a thumb activated user interface. Personally, I applaud their choice of batteries. Eneloops are great. I am becoming tired of babysitting a half dozen different LiIon batteries that are just waiting for me to leave them in a light with parasitic drain or just use them to long, drawing them down to far so they can become useless. The beam is incredible. I have lots of 4 die emitter lights and none of them have a pure beam like this. It does indeed look like a single die beam and it is bright!
 
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PhantomPhoton

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Re: Fenix TK40 Review

Nice review, thanks.
I have to agree that the UI is less than desirable for my personal tastes. But it isn't necessarily a dealbraker. Sounds like Fenix got the output and the beam profile done just about right. I'll have to play with one before I can decide.

/rant on :mad:
I have no idea why Fenix is afraid of 4 AA's being damaged by that drain though. Quality NiMh don't break a sweat until about 5 amps. :ohgeez:
I understand that it's flashaholics wisdom, and not that of "Joe" which says the performance of a flashlight is limited by the quality of the cells that power it. Any bozo who'd pay $150 for a flashlight (that's me) deserves what's coming if he uses cheap cells in said flashlight.
/rant off

2 mA parasitic current doesn't have me too thrilled either. That means you've got 83 days till a set of eneloops are flat if my mental math is correct. Hmmmmm :thinking:
 

woodrow

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Re: Fenix TK40 Review

Great review Wattnot, Thanks! I like this light...mainly for its great wide spill...and 500+ lumens of light. I am not sure how I feel about AA's (though the light is very noticibly lighter with 8 lithiums in it...though they only stayed in there for 2 minutes...way too much money to spend powering the light that way in this economy)

I liked your beamshots because they showed the light could keep up with the ROP...and was much more usable than the Tiablo Q5. The Surefire crack also made me chuckle.

Again, great review...thanks

Oh...I forgot.... How long would it take the parasitic battery drain to really affect runtime or output? A week...a month?
 
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KBOy

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Re: Fenix TK40 Review

Great review!
nice light

:twothumbs:twothumbs
 

nin82

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Re: Fenix TK40 Review

Thanks for the review, I appreciate you measuring the current draw
 

jirik_cz

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Re: Fenix TK40 Review

/rant on :mad:
I have no idea why Fenix is afraid of 4 AA's being damaged by that drain though. Quality NiMh don't break a sweat until about 5 amps. :ohgeez:
I understand that it's flashaholics wisdom, and not that of "Joe" which says the performance of a flashlight is limited by the quality of the cells that power it. Any bozo who'd pay $150 for a flashlight (that's me) deserves what's coming if he uses cheap cells in said flashlight.
/rant off

FYI I've measured one hour of flat regulation in turbo mode with 4 sanyo 2700mAh cells. No problem for them, but I wouldn't recommend that with alkalines :)
 

Ryanrpm

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Re: Fenix TK40 Review

It very well may stand up just fine but if you were set up a cage match to the death by filling a clothes dryer with M6s and TK40s, my money will go on the M6s.


Love this comment!!!:crackup::crackup::crackup::crackup:


And, very nice review!! Keep up the beamshots...can never have enough of them.
 

BrightMan

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Re: Fenix TK40 Review

Question about the switch, is it like the one from TK 10, tip and hold WITHOUT click and light is on or does the switch always have to click?

Runtime in turbo should be 2 hours, but if current is ~2.7A 2700 mAh NIMh cells will be out of power in less than 1 hour?
 

Outdoors Fanatic

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Re: Fenix TK40 Review

Your ROP High seems to be severely underdriven... or perhaps, it is about time to stop spending on lights and save for a better camera? LOL
 

flasherByNight

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Re: Fenix TK40 Review

Great review thanks, I've added you to my roundup thread! :)

The parasitic drain is almost a deal breaker for me...this is a light I'd like to be able to toss in my truck and forget about till I need it. hmmm
 

Kilovolt

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Re: Fenix TK40 Review

The parasitic drain is almost a deal breaker for me...this is a light I'd like to be able to toss in my truck and forget about till I need it. hmmm


It is very simple: you toss it in your truck with the tailcap loosened like you would do with any other light that has a lockout facility. :cool:
 

Wattnot

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Re: Fenix TK40 Review

Thanks for all of the positive comments! Now to address some questions:



Thanks for the review would you say this light is worth for its price?

For me it is not but that is only because I really don't have a need for it (or at least haven't yet). If I were a cave explorer or in law enforcement or heavily into night hiking and bike riding then sure, this light is worth the discounted CPF price.



Question about the switch, is it like the one from TK 10, tip and hold WITHOUT click and light is on or does the switch always have to click?

Runtime in turbo should be 2 hours, but if current is ~2.7A 2700 mAh NIMh cells will be out of power in less than 1 hour?

The switch doesn't actually "click." That's why I used "quotes" above. It is a momentary contact button that controls logic circuitry. You can fully operate the light by taking off the tailcap and shorting the bottom contact of the battery holder with the threads on the battery tube momentarily. As for runtime, I would test it if I had the 2700 cells but some simple math can be applied with my current draw measurements. Keep in mind with 8 batteries your 2700ma batteries are really 5400ma. I had to edit this post TWICE because I kept forgetting that.


Your ROP High seems to be severely underdriven... or perhaps, it is about time to stop spending on lights and save for a better camera? LOL

I'm not sure why you would say this. Maybe this should be taken as a compliment for the TK40? Are you upset because an LED matched it? :devil:

I have a new Canon DSLR but again, these pictures were taken in haste, in a downpour, because a review HAS to have some beamshots but I didn't want to hold it up another week. The batteries in my ROP were not topped off but should have been at least at 75% capacity. I'm using AW C lions. As for the camera settings, I manually set the exposure, trying to straddle the outputs I was working with. Technically the ROP and TURBO TK40 shots were slightly overexposed and the rest were slightly underexposed. I felt it important to use the same speed and arpeture for all shots for comparison purposes.


Just something I didn't mention about the battery carrier in the review because I thought everyone knew but with 8 batteries installed, you are getting the voltage of 4 batteries at double the available current (or capacity). The battery configuration is 4S2P which means 4 batteries are in series, then the other 4 are in parallel with the first 4. If all 8 were in series (wired end to end) you would get double the voltage and the rated capacity of any ONE cell.
 
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flasherByNight

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Re: Fenix TK40 Review

It is very simple: you toss it in your truck with the tailcap loosened like you would do with any other light that has a lockout facility. :cool:

sounds like it's gotta be hanging on by a thread, and tailstanding....not exactly like "any other light"
 
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