Modding a Trustfire TR-J12?

[Fadelight]

I've been doing a lot of reading trying to learn as much as possible about modding flashlights, but half the time I spend reading is when I'm half asleep. That said, here goes...

I've been eyeballing the Trustfire TR-J12 lately, but it seems the XM-L's are only being driven to half their potential on that flashlight. If my math and understanding are correct on the subject, an XM-L can be run at 3A, but the flashlight uses a regulated drive with a 7.5v output (1.5v per LED). If this is the case, then theoretically I can upgrade the driver, correct? If so... what is my next step in reading so I can figure out what I should be looking for with boards and batteries? The boards all seem to only state their input and output, and that may be correct, but it just seems to me like there should be more to the equation than that? And batteries still confuse me as a whole. I have trouble with what part of the specs deals with output and which deals with battery life.

Any advice/ corrections would be greatly appreciated!

 

[PapaLumen]

Me too... Thats 7.5A by the way not V. So each led sees 1.5A and as you know can handle 3A.

There doesnt seem to be a single driver out there to do what we want from 3? batteries.

The led's are in parallel so to run them all at 3A you would need a driver that can output 15A from 3xbatteries.

Also would need to be IMR batteries to handle 5A from each.

 

[Fadelight]

Haha the volt thing was my phone auto correcting... I typed "A".

If I've been reading correctly about batteries and drivers, we could use batteries that output anything over 5a each and be OK if the driver were regulated.

I keep reading mention of boosted drivers which - from what I can tell - output higher amperage than they draw... which to me defy physics. So there's a 99% chance I'm not understanding that correctly.

 

[xed888]

Modding it to 3A per led would make it too hot too quickly. There isn't much point. You could direct drive it ie get rid of the driver and just connect it to the batts

 

[Fadelight]

For how I use my flashlights, they are only on for seconds at a time... usually 1 minute at most. For that reason, heat is seldom an issue.
What batteries could be run DD to produce the 15a? The only batteries I can think of off the top of my head are 18650s and they are 2200mah.

 

[PapaLumen]

A boost driver raises the VOLTAGE. Buck driver lowers it. I agree it could only be used for short periods.. You can get IMR 18650's which can easily handle 5A but may give too much current when used direct drive.

 

[Fadelight]

But if those batteries fit OK and produce the correct amperage, then a driver could also be found at that point, correct?

 

[PapaLumen]

Nope, if you find one let us know :D You could get 9A with a der wichtel driver for a little improvement i guess... - http://www.candlepowerforums.com/vb/showthread.php?276105-High-efficient-5A-9A-Buck-Converter-for-SST-50-SST-90

Or if you wired the led's in series you could get 2A to each led using something like a taskled boost driver... - http://www.taskled.com/hboost.html

 

[Fadelight]

Ugh! I guess its direct drive and risk overcurrent, be happy with the light the way it is... or go with the 3 xm-l version and mod that instead. (I'm leaning toward the later at this point. )

 

[PapaLumen]

I dont think there would be enough voltage direct drive from 3 batteries. 5x XM-L would have a forward voltage somewhere between 15-17.5V. 3X18650 would give 11.2V (pretty much discharged) - 12.6V (fully charged).

 

[Fadelight]

OK so changing the focus... what options would I have for driving 3 xm-ls with 9a?

http://www.amazon.com/gp/product/B006JWP97C/?tag=cpf0b6-20

It claims to be 3800lm which I very seriously doubt... BUT... in that configuration it should be possible to get 9a to those leds, yes?

 

[PapaLumen]

Ok, an xm-l is rated at about 10watts power at 3.3v, 3A (3.3x3 = 9.9watts) So with three of them you can either run them in series, (add the voltages together) = 9.9v @ 3A.
Or, in parallel (add the current draws together) = 3.3v @ 9A.
In series would be the preferred method because if in parallel, if the leds are slightly different, then one could draw more current than another resulting in different brightnesses of the 3 led's.

Im not sure what model that one is you linked to is but i think most of those 3x xml lights are pretty much good to go as they are. Only the 5x xml light seems to be very underdriven. If you search on here for 3x xml lights you should see a good selection with tests etc.

 

[Fadelight]

Ah... ill do some searching then. Thanks!

 

[Shadowww]

I keep reading mention of boosted drivers which - from what I can tell - output higher amperage than they draw... which to me defy physics. So there's a 99% chance I'm not understanding that correctly.

Yeah, you're misunderstanding it in terms of difference between current & power.
Defying physics would be a driver that outputs higher _power_ than it draws, not current. Power = Current*Voltage. So if input voltage is higher than output voltage (e.g. 2x LiIon -> 1x LED driver), output current will be higher than input current).

 

[Fadelight]

Ugh. I feel stupid for having missed that part... I should know better. Thanks for clearing that up for me.

 

[MomentumExchange]

I have modded the TR-J12 with this driverhttp://www.kaidomain.com/Product/Details.S020417 which is rated at 50-60W. The modes are 100%, 75%, 50%, 30% and 5% and the PWM frequency is 1000Hz, and so not visible to the naked eye. 50% on this driver = 100% of the existing driver. On high, it runs for about 5-6 minutes before thermal protection kicks in and drops the output. It becomes hot to the touch in this state. 50% runs nice and cool. I am using SenyBor High Drain (2C) 18650s x 3 and they can easily supply the required current. The output is about 4000 lumens OTF (reported) and the beam is extremely impressive to say the least. Apparently, the driver intially dumps 77W through the LEDs and is throttles to 25-30W, as someone has reported on BLF. I have attached some beamshots for your viewing pleasure :) (I have a thread on budgetightforum as well). I hope this is useful.

Beamshots (enjoy!): (@ ISO1600, 1/10sec, f=5.6, Daylight WB, Manual Focus on a Nikon D50 with 18-55mm lens)
5%

50%

100%

Example of throw: (trees in the gap are at least 150m away lit up no problem)

Example of spill: (literally a wall of light!)

Control shot:

and on full:

 

[MomentumExchange]

I've been doing a lot of reading trying to learn as much as possible about modding flashlights, but half the time I spend reading is when I'm half asleep. That said, here goes...

I've been eyeballing the Trustfire TR-J12 lately, but it seems the XM-L's are only being driven to half their potential on that flashlight. If my math and understanding are correct on the subject, an XM-L can be run at 3A, but the flashlight uses a regulated drive with a 7.5v output (1.5v per LED). If this is the case, then theoretically I can upgrade the driver, correct? If so... what is my next step in reading so I can figure out what I should be looking for with boards and batteries? The boards all seem to only state their input and output, and that may be correct, but it just seems to me like there should be more to the equation than that? And batteries still confuse me as a whole. I have trouble with what part of the specs deals with output and which deals with battery life.

Any advice/ corrections would be greatly appreciated!

Hint!: Use this driver (custom spec by bose301s!!): http://www.kaidomain.com/Product/Details.S020417 which was custom designed to mod this light and either AW IMRs x3 or SenyBor High Drain 18650s x3 work extremely well. 26650s work well also, but there aren't very many decent ones out yet so I've stuck to 18650s. I've got another post with beamshots from my modded TR-J12 as well as more info.

 

[jmpaul320]

wow im glad i found this thread... i have a tr-j12 and was thinking the other night while taking a walk... man this thing is bright, and its only pulling half what it could per led... i wonder if anyones modded this....

hmm... for $20 ill bite... i have been meaning to get some more 26650 imr now that theyre available from a good source in the marketplace as well... so this is a good excuse as any

this gets me thinking... anyone done a 7 or 9 xml KD driver swap :devil: probably translate into 100+watts of pipe bomb goodness!

 

[kramer5150]

Just make sure you upgrade your springs with copper braid. I melted the OEM springs in mine just using the stock ~28W driver on a 25 minute run with 2x26650

This light is a beast thats for sure. Now that it can be found for less than $50, its a good deal too.

 

[jmpaul320]

Ya. I paid 58 for mine . good light