ok. me and toni had yet another hospital visit today, which meant an afternoon free without the kids running about.
I decided to have a little time in the gords cave, I had a light to build for my bosses wife, wanted to mod an atomiser or two and…….
I’d got my fluke sorted out for accurate current readings (um……it needed a new battery lol) anyway, I figured some readings from mine would tell us if there’s an issue in johnnymacs. The results suprised me tbh.
first I did a tailcap reading with my depleted feilongs, I’ve been playing but that reading might have told me something.
I got 3.4a at the tail on turbo, that to me is very much in line with johnnymacs readings so I decided to go into the head and do an emitter reading, I stuck the feilongs in the charger and decided it was getting the best shot I can give it for high emitter readings - fully charged molicell 26700 cells………
this also meant we’d be testing the full circuit, so what I get here will be what I get with the light buttoned up. Result…….
3.46a in the emitter circuit.
Johnny, I don’t think your build is the issue or your cells, I don’t think the dry driver is letting the emitters see full direct drive.
I’m going to order one of the lck led drivers like the ios one tom e likes and fit that, but I think our real issue is the springs used to make contact from the hold down disk to the driver plate.
I am going to pull the reflector again and see if there’s a frequency reading on turbo, it might tell us if the output is full output or a pwm output. I suppose the other way to check is to video the beam on all modes and look for bars on the screen.
Thanks for checking out the readings. I have to say it’s disappointing. I still don’t understand why he is getting such low lumens though.
I just did a spring mod on mine to see if it changes anything. I unscrewed the part that hold the spring and fed a piece of copper wick through the spring and then soldered it onto the plate. Then I screwed the spring back on, trimmed the copper to size and soldered down onto the spring. So now the spring is bypassed. I’m recharging the sony’s I use and will see tonight if there is a noticeable difference. It was very quick and simple to bypass the spring and I should have thought of it before. You could give that a try and see what happens.
I’ll certainly have a play, I’m even considering a piece of copper tube to replace the spring lol.
this in no way reflects on your build either, I’ve no issue there and don’t want people to interpret that I have, I’m just reporting what I found and what I’m thinking of doing next, I don’t think the issue is either cells or wiring, its either the contact points in the light or and this is just a wild theory here, the emitters are being kept that cool that the vf is being kept too high to allow the current we are expecting through before the cells sag. There, I said it, perhaps we have gone too far, although I’m confused with the molicells, those things can drop 100 amps, they really shouldn’t be sagging so maybe my guess is wrong here.
I did pretty much the same thing as 18650 and JohnnyMac (copper, heavier gauge wire, dry driver). With MNKE 26650s, I pull a little over 4a with fresh cells. Did you add a copper braid to your anode spring? How did you mount the dry driver? I think something is amiss with your setup or your multimeter.
I was pulling amperage close to what you’re finding, but when I took everything apart and fixed the placement of the anode spring (by tightening it toward the driver) and adding a copper braid to it, I broke 4a.
I've seen DRY drivers having relatively high resistance, because even 4A is disappointing for a supposed direct drive. The IOS type driver (well, the LCK-LED 5A now) seems to do much better in direct drive mode, and no turbo timeout. Not many choices out there unfortunately for drivers, and the DRY is for sure a low cost option.
Tom, do you have any idea about the efficiency of the DRY? I know I could figure it out by desoldering one of my LEDs and measuring emitter current and voltage, but I’m lazy. I’m assuming it’s pretty efficient because the voltage drop isn’t that big between 3 lipos and the vf of 3 xm-l2s inseries, but I figure if anyone knew it would be you.
Well, didn't do formal tests, but head to head in a Shocker, there's no comparison. The IOS or LCK-LED driver can do 5.5-6A direct while the DRY does 4-4.2A or so. 3 cells in series, 3 LED's in series - same setup.
According to the calibration certificate there’s nothing wrong with my fluke
I don’t think the positive connection is braided as yet, tbh, I’ve not done much other than use the light as I’ve been busy with other things.
once I get my PayPal sorted out, I’m going to order some more of the lck led drivers and give one of them a go, I do have one here already but its in an xp-g2 convoy l2 and I’m loathe to pull that appart as I like it as is for now.
JohnnyMac,
18sixfifty success was also the reason i started the TR-J19 project and i do not regret it for a second.
It was not very cheap but it`s well worth it. What a monster of a light it became after modding…
Flashlight + 3 x noctigons xml2 u2`s + dry driver + 3 x 32650 trustfire batteries + charger makes a total of ~170$
I swaped the original XM-L2 with dedomed noctigons XM-L2 U2 1A,
Cooper braided the cathode and anode springs,
The centering spacers were trimmed flat, now they are not blocking any light and the reflector can sit as low as possible, for the best hotspot,
The Dry driver was also modded by changing the transistor with a lower resistance one. A custom brass ring had to be machined in order for it to fit,
Installed thick wires for the driver and emitters.
Thermal paste on the pill threads for better heat transfer.
I have tested the modded dry driver on my test bench, using a 12v 6Ah lead acid scooter battery, i could measure at the emitters 6,2A on turbo.
Installed in the flashlight, the same scooter battery, measured at the tailcap i could see a maximum of 5,5A on turbo.
With the 3 x 32650 protected trustfires the tailcap measurement is “only” ~4,5A. Don`t know why. I was expecting the same 5,5A.
I have tested individually each 32650, they can easily deliver 7A before the protection kicks in.
I am very impressed by the performance of the modded light.
I do not have any exact numbers for the lumens or throw but,
Based on the fact that a cooper XML2 delivers 1500 lumens at 4,5A, it is around 4500 led lumens, probably slightly less because of the dedome emitters.
Based on 18sixfifty klux test it should be around 350 Klux.
Tested on the field i could see being lit pretty well a target building at 1200 meters.
JohnnyMac, any updates with your J19 ? Did you install the new driver? Do you have new numbers?
