Yeah, 17 watts - 22 watts is no way correct. It should be at least up into the mid to upper 30 watts range. Keep the updates coming.
Hey, I got mine today. Can’t figure out, how to remove the reflector? Are there not a custom drop-in module? Should the driver be screwed out to gain access to the screws holding the reflector?
Btw the light force doesn’t impress with the originall driver at all. My modded TR-DF003 with three xm-l has the same brightness or even brighter… This has tighter spot though.
Uh oh… just figured out myself. damn. This is not going to fit my purposes to be disassembled and used in a custom made diving lighthead… I thought it would’ve been something like this:
Pretty amazing test results with the Intl outdoor shop driver!
From the driver to the leds: 3.04 A / 22 V = 66.6 W
Tailcap: 6.04 A / 12.12 V = 73.2 W
So this driver seems to be also really efficient: 90.9 %
I’m back on the drawing board. Gonna build a whole new lighthead suitable for diving with a battery canister…
Agree - I measured 5,500 lumens with the IOS driver using 3 KK batteries - swapped my mod'ed one for a stock, now ordered another IOS driver - will do the same.
+1… thanks Tom 
Didn’t quite get the last sentence, did you take out the IOS driver and put back the original or what? Did you mean you’re also building a dive light by that “will do the same”?
Ooops, sorry. No, I swapped my mod'ed J18 with another BLF member for his stock J18, so now I'm back to the stock J18, which means I'm upgrading to the IOS driver again 
.
I just can’t get the driver out… the copper loop on the inside sits so that it won’t fall out no matter how I try to manipulate it… is there a trick?
I’ll put this here also
Didn’t understand that wound copper wire thing, mine had nothing else keeping the driver than the power wires. The reflector is not glued, it’s attached with two screws which you can loose from the inside after moving the driver away. The leds are glued to the frame. Silly way since you can’t take out a “drop in”…
Few days ago I figured out that the frame is separateable to two pieces, if one would like to do some additional plotting…
jaws - didn't have that problem with mine - driver came right out. Got the pic in the other J18 thread to show it dangling. Not sure what you can do...
A pic would help a bit? Maybe jammed threads if you mean the copper ring that keeps the spring against the driver?
Is there a way to mod in a variable control switch in the tr j18 and if so, where to get one that fits that monster?
Managed to get it out - now to determine the fault. It took a lot of force to remove. The copper coil on the board had bent out a little so I needed to pry with a lot of force on an angle to remove it. Pushed the copper coil back down now it slides in and out easily. Still works too, albiet the same at only up to about 50% power…
Anything is possible, but no simple way for sure, that sounds like some decent amount of engineering (EE/ME) work...
I looked around for good tailcap switches after I blew the original after attempting a resistor mod on my stock driver.
First I added a resister in parallel to the current sensing resistor to get to 50ohm from 150, then I added some extra mini cylindrical magnets between all the nano lithium A123 cells I use and the tail cap until the tailcap blew from the extra power!
I tried replacing it with a larger switch from a broken vacuum cleaner however it wouldn’t fit in the tailcap.
I thought all hope was lost until I was fiddling with one of those budget 5 dollar bulb torches that use those 6v super heavy duty alkaline batteries - I noticed a perfectly sized switch for the button. A quick swap and it works!
Also, put the vacuum cleaner switch back in the 5dollar cheapo light and modded a spent 6v alkaline battery to store a 2s2p 18650 lithium battery pack with balance charger connector 
and now that little beast is always ready to shine since those alkaline batteries are notorious for dieing horribly when your not watching.
The resistor in question is the flat one directly adjacent the large yellow component on the circular pcb in this image:
http://i.imgur.com/orXD3yB.jpg
It is quite noticeable thanks to its wider and flatter design. Mine measured in at 150 ohms. I did a parallel resistor calculation and found a 75 ohm resistor added in parallel would give me the 50 stated in the OP. I wanted something easy to remove if things went wrong (such as flashing/flickering/low beam/etc) so I went with parallel resistors and Surface Mount Component Fix from Fixit products.
I found a 75 ohm resistor using a multimeter and an old graphics card board and just popped it off with one of the multimeter probes (surface mounted) and prepped the current sensing resistor using the Surface Mount Component Fix. It is basically a conductive glue like wire glue intended from surface mounted components. I applied some component fix to either half of the original resistor as the 75 ohm resistor was significantly smaller than the original and made sure to cover the two tinned ends of the original.
After letting it dry I applied the 75 ohm resistor directly above the 150 ohm resistor and put a generous coating of surface mount on either end. I checked with a magnifying lens and my T6 torch to ensure there wasn’t any shorting with nearby components, scraping off excess component fix with a pin.
Initially I thought I had failed as the flashlight was very dim after a short burst and it took me a while to realize that the batteries were drained (3.3v across 3x3.3v batteries!) and so I charged them up (ah the beauty of LiFe nano lithium) and it blazed away for a good few seconds before the tail cap blew. I used some angled long-neck tweezers to open the tailcap (alternatively use the multimeter probes) and it smelt acrid. The rest was pretty easy once I had the correct switch, just heat your soldering iron for a good few minutes and apply to the circular tail cap board on whatever solder you can to remove the old and replace with the new.
I had a few issues with the torch not lighting the first few times due to a poor connection, so I re-coated the circular board with extra solder wherever there was exposed trace to increase conductivity and reduce heat. This thing blazes!
I recently won an ebay auction for one of these flashlights for $43. I am so looking forward to trying this mod. I have ordered the I/O driver board and have already replaced the tailcap switch with the 14V 10A Judco switch that was mentioned earlier in this thread. In order to make the Judco switch fit, you have to pry it apart and remove the copper components from it so that you can cut the switch housing down to a square. Then put it back together and bend to copper leads so that they will fit. Once you do that, you can file/sand the original switch keeper (the round plastic piece with the rectangular cutout) so that it will fit around the Judco switch. Then just solder it to the pcb that the old switch was mounted to and then beef up the current carrying ability of the spring by soldering a piece of braided copper wire.
As far as batteries, I had a 36V dewalt power tool battery that had a bad cell. So I disassembled the pack and tested the cells individually. I ended up with 9/10 of the cells being good, measuring 3.2 to 3.3V each. These are the A123 Systems 26650 Lithium Iron Nanophosphate cells that the poster above is using. Topoff charge on these is 3.6V. The trustfire TR006 charger has a switch on it for 4.2V and 3.0V. I think the 3V is in error because it does in fact bring these cells to 3.6 to 3.65V on this setting. Too bad these cells are only 2300mah, but I guess that is the tradeoff for being able to sustain 70 amps per cell.
So far the light is working great and is very impressive with the stock driver. I guess I need to get a lux meter so that I can do some before and after measurements to see how much increased output I get from the new driver. Any good recommendations on a decent lux meter?
I am sat here with my tr-j18, and those nano phosphate cells sitting comfortably inside, and I can’t help but be irritated to the fact that those cells drain so quickly at high mode.
Now I generally use the torch on low mode and love the excellent feature of being able to remember the previous setting, and even the fast charge rate of 3.5-4.5A, however I think a torch or mod needs to be tailored specifically to these cells.
What I was thinking would be to have from dual to quad cells in parallel such as in the sky ray king and nitecore tm26, or a mod that uses a DC step down module to power a tr-j18 from a 33v battery pack.