My quick review of the Fenix TK40

TallNHairyDave

Newly Enlightened
Joined
Mar 29, 2008
Messages
167
Location
London, UK
Well, it's arrived. So here goes with a review.

The box when it arrived from Heinnies was smaller than I was expecting and contained my order of two MaxP Volta battery cases, a set of MaxP Sliplocks and the TK40:

tk40review-01.jpg


Sliding the cardboard outer off revealed an inner, translucent hardcase:

tk40review-02.jpg


With fold up handles (nice touch)

tk40review-03.jpg


Opening that revealed the torch and it's accessories all in handly compartments (downside - the metal clip of the shoulder strap has very slightly marked the tailcap of my torch - just visible as a white spec in the photo. In reality, the scratch is about 1mm long.)

tk40review-04.jpg


The downside of the case (apart from that mentioned above) is that the moulded hinges seem quite thin to me, and I'm not sure how long they'll last for if you use the case as a storage/carry option for the torch regularly. Still, the fact that the torch comes with a custom hard case is a nice touch.

Unpacking the case reveals:

tk40review-05.jpg


Clockwise from the bottom:
  • TK40 torch
  • Shoulder strap
  • Instruction manual
  • Warranty form
  • Small advertising brochure
  • Ziplock bag containing spare tailcap, 2 spare O-rings and a split ring
  • Mystery woven lanyard thing


Now, a lot of the quick reviews I've seen so far of this torch seem to have failed to figure out what the mystery lanyard is for, and it had me stumped for a while as it's too damn short to work as a wrist strap. But I finally figured it out!

Moving on, I decided to compare the size of the torch to my Solarforce L2 (which is about the same size as a Surefire 6P). You can see in this pic how the shoulder strap attaches. Oops! I've given away the surprise I was saving for later in the review!).

tk40review-06.jpg


What strikes me is that the torch isn't HUGE or too heavy, even with 8 AAs in the battery holder. You can carry it in your hand without getting tired.

Speaking of the battery holder... To get it out of the torch, you can unscrew the head or the tailcap. The gotcha being that the bit of the tailcap you expect to unscrew doesn't - it's the very tailmost ring that unscrews.

tk40review-07.jpg


Here's a closeup of the battery holder loaded with eneloops. It looks exceedingly well made and does the job nicely. Batteries go in the holder with the negative side towards the spring.

tk40review-08.jpg


Thinking of batteries, the manual tells you to unscrew the head 2.5 turns when not using the light for a while to avoid slow discharge of the batteries. Not sure why this should be so?

Meanwhile, back to the mystery lanyard thing...

tk40review-09.jpg


You attach the split ring through one of the two holes in the tailcap and clip one end of the shoulder strap onto that....

Then you loop the mystery lanyard around the head of the torch and clip the other end of the shoulder strap onto that....

et voila!

tk40review-10.jpg


You can then carry the torch slung over your shoulder. Nice :D

Operating the torch is pretty simple and is ALL through the tailcap clicky switch.

  • Pressing the tailcap switch turns the light on and off, and it remembers the last PRIMARY mode (low, medium, high, turbo) you used.
  • With the torch on, hold down the tailcap button for 1 second to go to the next mode. (You have to release and press again for 1 second to go through the modes. Keeping the buton held down does NOT cycle through modes)
  • Double-click the tailcap switch to activate the flashing mode that goes with the power mode you are currently on.
The flashing modes are as follows:

  • Low power = Slow flash (About 2 seconds between flashes. Would make a good locator beacon?)
  • Medium power = SOS (This is a SLOW SOS flash in morse code)
  • High power = Fast flash (probably around 1/2 second between flashes?)
  • Turbo power = Strobe (Holy !&$# That's disorientating!)


If you have it flashing and turn the light off then on again it comes back on in the PRIMARY (non-flashing) mode.

Turbo is DAMN BRIGHT, but they warn you not to use it for more than 15 minutes at a time.

Indoor beamshots to follow when it gets dark! Will get some outdoor ones at the weekend.
 
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By way of experiment, the Mrs just zapped me with it on Turbo from about 7 feet away. (I.e. literally just flashed it up so the hotspot was on my eyes and then dropped it back down again)

Turbo alone made me shut my eyes and flinch away.

We then repeated the test on Strobe.

Holy *expletives deleted*!!!

DO NOT TRY THIS AT HOME KIDS!

I now have a persistent purple "donut" in my vision which is slowly fading away.

I was prepared for it, and the test was done in a fairly bright room.

God knows what it would be like with dark adapted eyes in a dark room / alleyway (i.e. if someone jumped out on you and you had this beast on turbo).
 
Thanks for the review. I look forward to the beamshots.

The manual says not to run it for more than 15 minutes at a time on turbo? This is the first time that I have seen any mention of this here! Here I was thinking that I could tailstand it on turbo and light a room during a power failure. But I guess it will get too hot doing this :thinking:?

That is really disappointing.
 
Thanks for the review. I look forward to the beamshots.

The manual says not to run it for more than 15 minutes at a time on turbo? This is the first time that I have seen any mention of this here! Here I was thinking that I could tailstand it on turbo and light a room during a power failure. But I guess it will get too hot doing this :thinking:?

That is really disappointing.

Thanks. Yeah, I was a bit disappointed to read the "15 minutes on turbo" rule as well - especially considering as they say it'll run for 2 hours on turbo with 2700mah cells. I guess they mean "2 hours, as long as you do it in 15 minute chunks" :(

In the "Usage and Maintenance" section of the manual it says:

The flashlights automatic overheating protection may cause the light to flicker during prolonged running in a hot environment. Please do not stay on the turbo mode more than 15 minutes. If this occurs please turn to a lower output mode to cool the flashlight. Normal operation will be restored once the light cools down.
Fortunately, high is pretty damn high and should also do for room lighting in a powercut.

When I do the indoor beamshots I'll try to remember to also get a couple in a dark room with it doing room lighting.
 
Here I was thinking that I could tailstand it on turbo and light a room during a power failure. But I guess it will get too hot doing this :thinking:?

That is really disappointing.

I wouldn't worry about that. Unless you live in a mansion, you won't need 630 lumens to light a room.
 
Thanks, nice piccies there, am thinking of one myself, as like me FENIX, and OLIGHT's
tabetha
 
It's just for people that don't understand they have to reduce power when the light get's too hot. The time you can run it in turbo will vary with the ambient temperature. 15 min is probably worst case scenario, in a hot envirement.

Outside with air passing over the light, or in a cool place it will probably never get too hot. They can't make a chart showing how long you can run it in different temperatures, you just have to use common sense. You're holding it, aren't you?
 
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It's just for people that don't understand they have to reduce power when the light get's too hot. The time you can run it in turbo will vary with the ambient temperature. 15 min is probably worst case scenario, in a hot envirement.

Outside with air passing over the light, or in a cool place it will probably never get too hot. They can't make a chart showing how long you can run it in different temperatures, you just have to use common sense. You're holding it, aren't you?

Indeed! I would expect if you were using this light caving/UrbEx or on a cold night outdoors you'd get more than 15 minutes on Turbo.

Also, I got asked on another forum where I posted this review whether or not the TK40 would fit in the Maxpedition Universal Flashlight/Baton Sheath.

And the answer is YES. But only just.

tk40review-11.jpg


The fold-over velcro main body flap is only just gripping onto the other body strap and is therefore reliant on the black velcro securing strap for grip. And you have to detach the lid, move it up and re-attach it in order for the lid to fit over the torch head. Thank heavens MaxP made that sheath so adjustable!
 
Great work on the review.

off topic: what size are those glow in the dark o rings on the bezel of your solarforce?

That is a cool idea too!

thank you
 
When you do your beam shots, would you consider also showing the beam of a 6 volt incan lantern (the kind with the large diameter reflector). If I buy a TK40, and there seem to be many reasons leading me in that direction, I'd like to know whether it will outperform my big old lanterns for throw and flood.
 
When you do your beam shots, would you consider also showing the beam of a 6 volt incan lantern (the kind with the large diameter reflector). If I buy a TK40, and there seem to be many reasons leading me in that direction, I'd like to know whether it will outperform my big old lanterns for throw and flood.

Sorry mate, I don't actually have a 6V incan lantern! The closest I have to one is a mains powered worklight, and something tells me that that will outdo the TK40.

Thanks, very good review, great pictures. :thumbsup:

Thanks :)
 
OK. Indoor beamshots just aren't working!

This thing has a spill so wide that I can't get the whole spill and hotspot centre in one shot!. Think I'm going to have to try again shining it at the ceiling!

Just about to pop outside and shine it at the wall of the house across the street from me to get some quick outdoor ones for folks.
 
I've been doing discharge tests every night. ~40F Outside temp, it doesn't even get warm in 2 1/2 hours. Inside @ 72F, I think it would get too hot unless tailstanding in a glass of water up to the top of the fins :devil:
G27
 
OK. Distance to target (House across the street side wall) = 13.75 meters

All photos taken at ISO 80, f2.0 for 0.5 second exposure time and have NOT been edited in any way other than to resize them down.

In each case, the torch was held approximately 6 inches above and to the right of the camera.

CONTROL SHOT - street lighting ONLY
tk40beamshot-1.jpg


TK40 on LOW power
tk40beamshot-2.jpg

You can just see the hotspot on the wall under the window frame and lighting up part of the frame.

TK40 on MEDIUM power
tk40beamshot-3.jpg


TK40 on HIGH power
tk40beamshot-4.jpg


TK40 on TURBO power
tk40beamshot-5.jpg


And for comparison - Solarforce L2 with Cree R2 emitter. Single mode Solarforce dropin.

l2beamshot-1.jpg


Will try and get some decent indoor ones in a bit.

This torch ROCKS :rock:
 
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Ahhh, that is what we like to see! Thanks for the outdoor beamshots!

Do you have any other light that you can put in there for comparison? Perhaps your L2?

Keep it up Dave, thank you.
 
No problems mate. I shall fish the L2 out and repeat the shots.

Although the L2 is a single mode only, so there'll be only one shot... :crackup:

EDIT - Now added to the original beamshot post.
 
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Nice photos. To me, the wall looks brighter close to the camera than it does closer to the beam center. When you do your indoor shots, I'll be looking to see whether these show a dark ring between the beam center and the area illuminated by side spill. How far away could you pick out say a large dog or a coyote? My problem is I want a flood with throw.
 
Bwanapete - I'll pop back outside and take one down the length of the street. Don't know how well that will show the flood or not because of all the street lights, but it might help?
 
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