Fenix TK40 with Collimating lens, beamshots

[Walterk]

For all you TK40 fans!

And to return some effort you put in sharing information.
I've bought this light after extensive reading on this forum, and learned a lot since.

Beamshots

The beam is nice and sharp, but dispersed speckles from the reflector are visible. I see through them as the hot-spot is really bright. You can see how the 4 Leds show through, a single die Led would be more exciting, but maybe not as luminous. The photo doesnt show the clarity of the actual image projected on the wall.

Beamshots with the standard-lens, and outdoor may be follow in time.

The lay out

The collimating lens is from an old slide-projector, its glas, dia.50mm, and has a focal length of 32 or 33mm.
The original lens is 1,5mm thick, and 54,5mm diameter.
The lens is hold in place by an extra thick ring, to prevent it from falling out. (The clear opening of the bezel is 50mm.)
The TK40 can not be focused by hand, and within the head there is little room to enhance performorance, thats a drawback. But hey, it works, its throwing lots more than the original lay out.

How to remove the front bezel

I used a torch, carefully heating the rim and when heated using gentle force to unscrew the parts. Dont overheat the electronics and dont crack the glas. The led-module and the reflector are not one part, it has an invisible joint between 2nd and 3th coolfin seen from the tail.
Led-module and reflector are both glued to the housing, dont consider to remove them in one piece.

For the whole story the tailcap:

I bought the light as part for a project I have in mind. A good light source, and a 300mm telelens would make a fun searchlight.
BUT ... I need some more redesigning to do.
As you can see the projected beam is little different and not more interesting than from just the flashlight with collimating lens.
Probably end up replacing the lenses with a collimating lens.
Admit, its a housing with great potential .

Luckily I managed to make some outdoor beamshots. Well, actually one that photo that is clear enough to be interesting to show you: (Different lens, 66mm instead of 52mm )

Grts, Walter

 

[Kilovolt]

Very interesting, thanks for sharing! :thumbsup:

 

[hyperloop]

Very interesting!! How far does your modded TK40 throw? Have you taken any outdoor shots yet?

 

[SuperTrouper]

That looks like a sweet optic on there.

+1 for Outdoor beamshots!

 

[berry580]

+1 for outdoor shot as well! =O

 

[jirik_cz]

Interesting mod Looking forward for some outdoor beamshots.

Can you post some detailed photo of the LED and star? It looks like the MC-E chips are wired in series connection.

 

[Liteskr42]

Thanx for sharing. Please continue with more as you progress!!!!! This is the kind of stuff that keeps it interesting on here. I wonder if this will get moved to the Mod section though?

 

[amraspalantir]

great mod.most interesting i must say.
will be keeping tabs on this thread.

 

[Walterk]

Added outdoor beamshot 66mm aspherical, see start.

 

[Walterk]

I have measured the intensity now I have both a meter and a replacement reflector:

Original reflector assembly 23.000 Candela
Aspheric lens in place of reflector-and-glas-lens 20.000 Candela
(Measured at 4,6 meter)

So,... Fenix did a very good job in choosing their reflector.
It will be hard to find an aspheric beating this factory-setup.

 

[CyberCT]

Sweet! Did you figure out how to get access to the driver? A neutral XML would be a great upgrade with a different driver. I have a TK41 that I don't use anymore and want to mod it.

 

[Walterk]

No I don't have a clue, it is epoxied in the barrel from what I recall.
Prying it out will harm battery contacts I think.
I would look for another host before going that way.

 

[CyberCT]

Hmm in that case I might just crack this thing open and try to swap in a neutral xml. I wonder the amperage draw from each mode.

 

[Walterk]

I have tried that, but it didn't work. The factory mounted MCE is a series quad die.

I've tried to change a MCE in a Fenix TK40.
It was connected with two wires.
The star made the MCE act like one single led with Vf of 12V instead of the common 3,2V.
Experimenting showed it could not be replaced with a XM-L, the driver gave trouble with all modes.
Eventually replaced the cool white for a warm white MCE, so opening up had a benefit.

I reverted to a star with a neutral white MCE wired in series.

 

[CyberCT]

So there's no way to do this huh? lame! The TK40 would have been the perfect host for a neutral XML. and OP reflector for floody beam and waterproof body for snorkeling.