Trustfire TR-3T6 95% good vibe, 5% bad vibe

LED Flashlights – General Info 18650 Flashlights
1

Hello,

This is the story of my journey from sadness to happiness with my TR-3T6.

First, some background.

I recently bought a Trustfire TR-3T6 on Amazon. I have a Dereelight DBS V3 3SM XM-L light with both smooth and light orange peel reflectors. This light has served me well as both a flood and throw light, but I was looking for a more blatantly bright flood.

Until I found this forum, I was convinced that I had to spend a small fortune to get what I wanted. HA! This forum has saved me hundreds of dollars already. Snooping around in the threads, I came upon the Trustfire TR-3T6, and it seemed like it perfectly fit my desires.

I had some Amazon credit to use up, so I went ahead and ordered it from there.

When it arrived, I was underwhelmed. About one out of 5 times it would actually turn on. I knew it wasn't the batteries because I was using Xtar 3100mAh Panasonic cells. I read on here about the tail cap "lottery" with these lights. Sadly, I lost that lottery. I concocted a make shift switch by removing the bad switch from its carrier board, soldering a couple wires in it's place, ran them out the tail cap into a very tiny external switch. It worked, but looked horrible. I tried searching for an exact replacement switch, but had no luck, other than an external pressure switch. I found a switch meant for the Ultrafire C8 for $1.90. It did not look a perfect match, but it was close enough to risk $1.90 on.

After waiting the normal Singapore to US dreaded shipping time, it finally arrived. Pulled out my "emergency, must use this light some way" switch, replaced it with the C8 switch, and "It's Alive!"

Finally I can test it.

First of all, I only measure 1.8 amps at the tail cap :( I will try the resistor mod at a later time. For now, it's still insanely bright compared to any other light that I have owned. I have had an MC-E in my Dereelight before, and that was the brightest that I have ever had previously. My XM-L with the light orange peel has a great flood, but it's nothing compared to this thing.

This thing also has a nice white tint that I really like. I was particularly amazed at the amount of throw that it has considering the size of the individual reflectors. This is definitely proof that price has nothing to do with intelligent engineering.

I can't wait to see what other jewels I can get my hands on without having to save for several months.

So, BLF and this Trustfire TR-3T6 has absolutely convinced me that price, name, and pretentiousness have absolutely NOTHING to do with the performance of a light.

2

Just wait until you do the resistor mod! Never has a $1 mod done so much for so little. 8)

3

I didn’t know this was that simple so I pulled out an 82mohm resistor, soldered it in parallel with the two 100mohm resistors already on there, and I’m at 3A draw per battery with 3 panasonics in series. I’m not sure what is going to each emitter, but I assume upwards of 2.5-2.8A. Nice improvement for an otherwise lacking light.

Edit:
Taken apart, these are the numbers I get with three Panasonic batteries near depletion (11.7v resting), on high:

10.15V/3.5A input
3.2V/7.7A output
67% efficiency…really need to rewire the light for the emitters in series and a new driver to boost this.

I tried 2 cells in series but the protection started tripping before my measurements were complete
?V/7.7A input
3.41V/7.65A output

4

Sorry, you may clarify what kind of driver are you talking about? Maybe yours has a different driver, in my not have these values ​​is R7 0.050 and R5 is not present.

Perhaps you purchased very recently from DX? It seems that in the last flashlight driver of this model is different …

Thanks.

A.

5

Hey JM…could you please point this blind man to a thread about the resister driver mod on the 3T6 you refered to, I can’t see to find it?Thanks…Rick.

6

You got it! It all starts here: Review TrustFire TR-3T6 Triple XM-L T6 5-Modes Memory LED Flashlight (3x18650)

7

So the inefficiency of the driver made this thing cook after being on for 5 minutes on high tonight. Also, compared to a stock 3t6 running itself on only two cells, the brightness increase wasn’t noticeable outdoors.

Here is what I got after having the light turn itself off and the leds putting out “moonlight mode” only:

On another note, my kaidomain $15 driver arrived today and it is a perfect fit. I’ll fix this driver, then try out the KD one.

8

The builders will use a single 50mohm if they have it, else they will parallel two 100mohm resistors which is more common to find. Both provide a stock resistance of 50 mohm. Adding an 82mohm in parallel brings the resistance down lower, allowing my light to pull 3A from the cells and put out ~2.5A to each emitter.

Losing 1/3 of the power to heat due to inefficiency in the driver though, that is terrible. There is no way around this as the driver is seeing 10-12V and only putting out 3.3-3.4V to the leds. That large gap causes huge efficiency losses.

9

KD Driver swap complete. Medium and low buzz pretty loud on that thing. Efficiency should be way up though as the LEDs are now wired in series, with the buck/boost driver, so it should still work on 2 cells (IMRs preferably). I couldn’t save the stock driver as one of the mosfets broke when I was trying to desolder it - it was fractured down the side.

10

It is not advisable to put three resistors in parallel, you would have had to remove one from 0.1 and in its place put a of 0.05, you would have 0,033 in total, what you need to get a great increase of light without cooking the driver. As you can see in the photo above, with three resistors others have made an omelette.
With the right value of 0.033 ohm light output is much higher and I personally tried up to 20 minutes in Hi without problems. The testimonies of others who have done the mod with the right values ​​do not seem so bad.
A.

11

I’m pretty amazed by the TR-3T6. Comparing it with just the eyes it’s just as comparable to the the TR-J12. I mean you wouldn’t noticed the difference in a blind. which comparing them side by side, it’s barely noticeably weaker in throw, intensity, flood etc…

12

Two 100s and an 82 provides 31mohm of resistance. Other than some resistors passing more current than others (the 82mohm), the driver itself will just see the 31mohms. The only problem with this is that the stock driver is VERY inefficient due to the 8-12v input and only 3v output - it dissipates a lot of heat. With that spread of numbers, all drivers are pretty poor. If the driver was buck, like my KD driver is, and the LEDs are wired in series, the input and output voltages are much closer together, greatly improving efficiencies. Efficiency like this is typically 90-95% while you will be in the 60s or 70s when going from 12v down to 3.3v.

Were the batteries providing adequate power? Did you measure the current going to the emitters? Without measurements, what you or others are seeing can’t be compared to the numbers I provided - 10.15V/3.5A input and 3.2V/7.7A output.

I can try to get some KD driver numbers to show the improvements it makes when you have your LEDs wired in series. While heat in LEDs is a waste, heat from the driver is an utterly pathetic loss of energy.

Edit
88% efficiency with the KD driver. 3.17A/10.8v input, 9.9V/3.0A output

13

I do not want to contest your calculations, reporting that only those who have done the mod with two resistors with the correct values ​​had a good surprise:
JohnnyMac
LumenHound

but whoever has used three fried the driver

In my TR3-T6 the brightness is increased by at least 50-60% , is comparable to Dry in turbo mode. If you have not noticed increase in light after mod, it means that something was wrong.

A.

14

That tan driver isn’t the same as what everyone else is using from clones. The entire thing is completely different. I have a lux meter, but I was comparing outside and to a buddy’s 3t6, not one I have available to do lux measurements. Either way, I still don’t think it compares to my original turbo DRY, I guess mostly because I have a neutral white DRY and everything higher color temperature looks terrible when outdoors. Blue will scatter the light much more and cause more glare, rather than illuminate and actually be much brighter.

Surprisingly, 5C tint makes 3C looks blue when shining the light at greenery. The 4K neutral-warm brings out the daytime colors of vegetation, rather than blue tints. Indoors, the 4k color looks very yellow though. I guess you can’t have it all yet - 4500-5000k white and high CRI.