S/F L4

[MEDIC15]

this is my first led flashlight and i was just going to ask you guys if there is any mods i can order.i would mod the thing my self but ummmm yea i really don't know a lot about the electronics of them.also i want to thank all of you for the reviews that you have done.it really helped me in my decision on what light was best for me

 

[admedeus]

Look around in B/S/T. There's generally some modded KL4's (L4 head) there.

 

[Erik Johnson]

In a way it's a shame this is your first LED (starting your meal with dessert). I too just purchased an L4. I ordered it on Tuesday and recieved it on Thursday from Bulldog. Two days USPS priority was a surprise; sometimes you get lucky.

I was going to wait for the L5 and L6, but I really like flood beams for everyday use, and also very much wanted to be able to use a single cell body (I also purchased an E1E, to make a TW4).

I don't have any answers to this topic's request but I do also have an interest. I would like to know what happens if I go with a Luxeon III with tight beam optics; can I switch back to my 5 watt easily? It sort of seems like a shame to mess with such a nice light. Would you mod a KL4 instead of a KL1 because of its driver?

Erik.

 

[tiktok 22]

Just got my L4 from bulldog. This thing is insanely bright. Definately worth the money(at least in flashaholic terms /ubbthreads/images/graemlins/crazy.gif)

 

[Chop]

The short answer is YES. There are mods for the KL4. The hot thing is to replace the circuit with either a BadBoy or DownBoy and replace the Luxeon with a 1W or 3W luxeon. You get good sidespill and lots of extra throw. You also gain the benefit of less heat and a bit more runtime.

The is no using an optic with the KL4. It's a reflectored proposition. Unless you acquired a spare heatsink from Surefire or someone else, you're gonna solder the pads on the sink to death going back and forth. Just get two of 'em. The problem with the KL4 in stock form is the McLux PR head. The PR is a little bigger, but it has very good sidespill and alot more throw than the KL4.

The KL1 and KL4 use different drivers. The KL1 uses a buck/boost driver and the KL4 uses a boost only driver. The only reason you'd mod a KL4 rather than a KL1 is due to the fact that the KL4 utilizes a reflector rather than an optic. If you don't mind the optic and the artifacts associated with them, the KL1 is killer.

 

[keithhr]

MEDIC15 , welcome to the cpf, it's a great place to be with a bunch of nice people.

 

[makar]

@chop: why does it make sense to replace a 5w (kl4) through a 1w or a 3w?

 

[illumiGeek]

[ QUOTE ]
makar said:
@chop: why does it make sense to replace a 5w (kl4) through a 1w or a 3w?

[/ QUOTE ]

It depends on what kind of light output you want. The 5W has a larger emitter and can't be focused as tightly, so you get more of a flood type beam.

If you want a tightly focused beam for long distance throw then the 1W or 3W works better because they have a smaller emitter (closer to a point source) and can be focused into a tighter, longer projecting beam.

Total light output is greater from the 5W for sure. So it's all a matter of brightness vs throw.

Aloha, iG

 

[makar]

thanks!

 

[Chop]

makar,
illumiGeek is right on. The beam of a 5W can be concentrated, but you need a larger reflector to do this and gain throw. The other advantage to going with the 1 or 3W in a KL4 is heat. Even running a 1W at 1A didn't get nearly as hot as a stock KL4 and the stock KL4 is actually underdriven a little.

 

[CM]

Using the Badboy in the KL4 is redundant. If you need a boost, stick with the stock circuit. However, you're limited to single 123 (using an E1e or a spacer in the L4 body) or a single Li-Ion (17670 size fits perfect). I have been using the stock circuit with a 1W high dome and Li-Ion and it's been a great light. Not sure a 3w would provide much benefit unless you get a T flux or higher. A good 1W is just as bright when driven to 3W levels. Just look at the numbers. If you use a 1W, make sure you use a Q or R flux. If you're worried about lumen maintenance of the 1W, just think how long you intend to keep this light. By the time the LED dims to the point where it's noticeable, we're on to brighter LED's or maybe the light would be obsolete by then.

CM

 

[Chop]

CM's right about this one. I don't even know why I mentioned the BadBoy up top. The mods that I've done have revolved around the DownBoy, and only to allow you to run it on 2X123's. I use Pilas exclusively in my 2 cell LED lights. My personal EDC right now is a KL4 that I use on either an L4 body or an E1e body, as dress permits.

The KL4 that I carry has the stock circuit in it and it works great. We can thank CM for this discovery. You only really need to get into replacing the circuit if you want to run it on more than a single li-ion.

BTW, my EDC has a Q3J in it, although I do have 3W's available. I wouldn't swap a good 1W for a 3W. You won't gain anything, not that I've SEEN anyway. Light meters might tell a different story, but my eyes aren't that sensitive. If you're starting new with a build or mod, I'd go with a 3W because they're cheap right now and the one's I've seen are at least just as good as the Q3J's that I've been so fond of.

To me, replacing the 5W LED with the 1W was a no brainer mod. I think the KL4 is now, much more useful.