Hi guys, I want a powerful flooder with a good cooling and the tr-j20 appears to be the most powerful passive cooling……
So, it worth or not? And about the resistor mod, its possible to reach close to 9k lumens with the stock driver?
Thanks.
Can you link the light in question?
Sorry, I forgot 
https://www.trustfire.com/en/flashlight-tr-3t6-3x-cree-xm-l-t6-3800-lumens-5-modes-3919.html
Oh yeah hav seen pictures of that one before, really cool looking!
You may want to take a look at
https://www.fasttech.com/products/1601/10000519/4173002
too. The head looks shorter, but of larger diameter. The cooling area seems somewhat smaller. But cooling strenght and cooling area are loosely related. Cooling ~= area * airflow. With deep fins so close together I don’t think TR-J20 will get much airflow, convection forces are weak and you need really low resistance to make it work well. Thought normally a light is in motion and even minor hand movements create pressure moving air around fins.
I wish someone did serious thermal modelling of flashlight, with CFD of airflow around it.
Get the Astrolux MF01.
Nowadays we have the MF01 and Acebeam X80 with whole bunch of emitters. It’s quite ironic that budget lights had this format for many years already.
Although I don’t plan to buy this TR-J20, but I am interested to know whether the stock driver can be resistor modded and produce incredible output, too.
That looks pretty cool, but would be better if it had genuine Cree emitters… :person_facepalming:
I have the Uniquefire S7 seven emitter clone of the Trustfire TR J18 and just resistor modded the driver last week. Even with the old first-gen T6ish emitters, it’s bright, finally brighter than my old quality SRK.
I’m back
So, I want some serious flooder with good thermal dissipation and that tr-j20 seems very good by some users told by not overheats easy. If that light can handle continuous 6~7k lumens it will be perfect :heart_eyes:
I took a look in that mf-01, but in reviews in only 3 minutes that light burn hands in turbo :confounded:
The only bad thing in that trustfire light is the very old led and cool tint :cry:
Get a modded one or mod yourself. :+1:
If it can do 6 klm with XM-L T6 and linear driver, it can do 10 klm with XHP50.2 and buck driver. 
Seriouly, those xhp50 can produce 4k lumens more and generates the same heat? 
So the 20k lumens range its possible? :heart_eyes:
Frankly, I doubt it actually can sustain 6k with XM-L T6. But yes, XHP50.2 is that much more efficient.
For a short period, 20k with 12 XHP50.2 is easy. It’s known to top ~4500 lm per emitter.
I’ve got the TR-J20 and did the resistor mod. Trustfire TR-J20 Update 8-11-14 The light get warm but nothing close to over heating. It’ll burn though 3-32650’s before over heating. Great light for a boost in brightness and swapping the XM-L T6’s for much newer better LED’s, Luminus SST-40 come to mine Mountain electronics has them Luminus SST-40 N5 6500K LED on Copper DTP MCPCB I would go to theses for the lower voltage used allows that current dipping draw not to affect the run time until the batteries were nearly dead. XM-L2’s and XP-L2’s at top bin would also blast just past the 10K lumen level nicely on a resistor mod using the original driver.
Very good, I read your thread and dont understand so much (my head is not working good this month :person_facepalming: :weary: ), do you have some links for those resistors and some pics of your driver mod and how this light disasembles?
Do you measure your output in that light?
Thanks for the input :+1:
Is there a driver that can handle 3S, puts out plenty of amps to a dozen or two emitters, and has a nice UI?
32mm HX-1175b1 - 7A Buck Driver comes to mind. Ask Richard at mountain electronics. Rumor has it he had a super Tr-j20 doing crazy output. Vinh Vinhnguyen54 | Candle Power Flashlight Forum is known to drive light a little harder than most.