Quick UF F-13 mod, for a member + beam shots

Here's a simple and quick mod for the F-13 light.


An F13, a Qlite 3 amp driver and an XM-L2 U2 1A on a Noctigon

Started at 10:20AM


Complete tear down in about 4 minutes. I will use the stock driver as a contact plate and I will be doing the copper braid mods to the springs. I will also add 4 more chips to the driver. I expect about 4 amps.


I have added 4 chips to the driver and I have soldered 18ga wire on the star.


Arctic thermal paste, (not adhesive), is under the star. The reflector will push down on the star, when it's all together.


I used a dremel to open up the stock driver, so it's an outer ring now, for ground. I soldered it to the Qlite driver. It's not very pretty, but it is held in place and it works. I wanted to add copper under the stock shelf, but with the 18ga wires and the extra chips, there just wasn't room. The stock shelf should be fine, it's thick enough and 4 amps should be ok, with no problems.


Driver is in place.

Modified light on the Left, stock light on the right.


Same thing, but with a slower shutter speed.


I did nothing to make the spot larger. It's simply that the modified light is putting out more lumens, so the camera shows a larger spot, due to a more brilliant spot. That's my story and I'm sticking to it...

Now, it's off to pack it up and send it off.... In a day or so that is. I got to play with it tonight first.

Just about an hour and a half, to get it all put together and under a total of 2 hours, to get everything put away and beam shots done.

Oh, it measured 3.97 amps with a Sony 26650 and a 20R 18650. It really does not have the room for a protected cell, at least the modded one doesn't.

Mouse Out = Modded HD2010 Mouse Over = Modded F-13


Mouse Out = Modded HD2010 Mouse Over = Modded F-13


Nice, those are the basic mods that make all them cheap lights instantly desirable :-)

Cheap basic upgrade…that is pretty much the defacto beginners mod right there…easy enough for practically anyone to do (other than the driver, moving the wire to the non-resistor side is the easiest but the Nanjg has alot better UI)

Awesome as always OL!

Oh there are a few contact rings made by wight that will help not have to strip stock drivers down


Thanks OL. You will have to come up with some hotrod mods that dont involve soldering.

Still beginner modding so looking forward to doing this this weekend (except adding chips. I would destroy them in the process, so I'll use a new driver) Thanks Old-Lumens.

Nice quick job! Wondering though, to get 3.97A from a 4.44A (3.04A + 1.4A) configured driver with braided springs, 18 AWG wires, on a XM-L2 Noctigon, low resistance cell, seems like it should do better maybe? I'm thinking I've seen over 4A, maybe over 4.25A on something close -- can't recall exactly.

Even at 4A though, it's a lot of light from a relatively small, cheap light for sure...

Other note - that centering piece is probably blocking a bit of output. Could be filed/sanded down or replaced with a flatter one, but you may run into issues of the reflector not fitting tight -- more modding, ugh.... Bigger mod job Frown.

Maybe one of the 7135's is a dud. That's why I like Warhawk-AVG's tester.


That’s a tail cap reading and I was having a problem making good contact with the end of the body. I really don’t like ground seating on just the end of the tube, as it is not much of a seat at all. Might be a bad 7135 chip, but I didn’t check right off the driver, so I can’t say for sure. I figure 4 amps in that light is way more than enough. I thought about the centering ring, but I am seeing that Mfgs are using them to “make a tighter spot”. At least that’s what they seem to be doing and with them. Cut down, the spill seems to be brighter. Well, that’s what my eyes tell me, but hell, sometimes I see spots with no lights on…Laughing

Well, that bonfire photo you had in your build thread is probably a “hot mod” and it doesn’t need soldering.Tongue Out

Added beam shots in the OP

Thanks OL. As usual nice shots. Do you think you can keep modding it until its brighter than the HD2010? No you cannot send it to me. Thanks again.

Thanks OL.

That white centering ring really does affect the throw and OTF I think and of course makes that weird perfectly round hot spot.

I’m not convinced the reflector is actually designed for an XM-L/2 at all, it just doesn’t seem to focus them right at all, and the white ring seems to be a last ditch effort to make is usable. I wonder if the reflector was really intended for something like an XR-E.