TK75 vs BTU Shocker - Let the battle begin! (NEW UPDATE ON POST 125)

I had XM-L2 U2’s installed… Had some resistor work done. It’s just under 4a on turbo… Really happy with it. ( btu )

Thank you rdrfronty for testing them out.
Your TK75 result match with runtime chart I have seen that output drop about 5% in 20 minutes Turbo mode. That is very good performance I would say.
No comment from me for BTU.

I confirmed from preliminary testing that the driver current does drop during the first minute or so. It started out at 3.7A and dropped to 3.5A rather quickly (emitter current). Nothing huge, but it should contribute a bit to the fallout. I’ll be tweaking my output a bit to compensate, shooting for 3.8-4A on turbo.
Once I move to XM-L2 U2 on copper, I might bump it up closer to 4.5A (depends on output curves from XM-L2 when they are done). This driver seems to be comfortable with high current output.

Thank you for the performance analysis and the temperature / lumens statistics.
Was really looking forward to your report.
Now, for a ton of light and extended use, the BTU is good with a conservative 10 to 15 mins on turbo and the rest on high. This is a 2000 + lumens light all the way until battery failure. Now, with a little tinkering, the BTU is set up for an even greater performance and greatness.
In the flashlight universe, rarely does a torch delivers both - massive throw and flood of over 2000 lumens all the way. The BTU is a truly living testament to all discerning owners and lovers of led flashlights.
Great job RDR. I am certainly impressed.

That slight current drop is good to know. Thanks for that little detail. So perhaps the light loses maybe 200 lumens or so due to heat and 200 lumens due to driver output dropping slightly.

I think a 200mA reduction across three LEDs would be quite close to 150-200 OTF lumens of loss (around 50 or so per emitter). The rest is likely heat sag. Since the driver sage is quite quick, one could compensate by jumping up to 4A drive, which would fall back to 3.8A within a minute.

so we all agree Ric Awes us a nice coated lens ??

I’ve been hunting around for one without much luck yet. Found one company, but they have a minimum of 25.
It would be nice of Ric would upgrade us, but I’m not going to dwell on it.

[quote=Shaquille]

My U3 has been shipped by fasttech and my soldering iron is all sharpened up tinned and ready muahahahaha

I strongly suggest to stop using that fujic crap .scrap it out and use a thin coat of "silver thermal compound" or artic silver and similar cpu products .It will greatly increase heat transfer from the emmiter

so heres my upgrade FOR MY BTU asap to beat the tk75 now



1- change over to U3 for higher lumens----AVAILABLE-



2- Remove all cheap fujic crap and use expensive silver thermal compound for better heat Transfer. ---AVAILABLE



3- change lens to ar coated lens -? ----NOT AVAILABLE--cant find ...hoping Ric has answer to this



This has been and informative and very excellent thread. Thanks to all participants. Both of these lights have been on my short list for a while. I’m now thinking of going with the TK75 even though it’s $70 more .

good choice :)

I was looking at getting a BS Terminator, but having seen the TK in action, this, and another review with the TN31mb, where the TK75 was the only semi-flooder to touch the target, went with the TK.

It's my most expensive light to date, and I couldn't be happier. One of the three LEDs is a bit off center, but I don't think it's affecting much of anything.

Has anyone upgraded their TK75 with the newer L2 led? Any report on its effect lumen wise?

[quote=Shaquille]

I have a possible source for a lens. Give me a few days to hopefully get mine in and to check fit & etc. If all is good then I’ll post up details on it for others looking.

[/quote]
I have a possible source for a lens. Give me a few days to hopefully get mine in and to check fit & etc. If all is good then I’ll post up details on it for others looking.
[/quote]

ok ,thanks fronty .

changed the led to xml u3 now and am satisfied with the btu output.got no light meter but i think its way above 3000 lumens .i can see the diffrence.I think 3 u3 driven at 3.8 amps should give around 3500 lumens???? ! AND I USED A SILVER ARTIC THERMAL PASTE . now the whole light feels warm within minutes on turbo .I guess that means heat is getting transferred from the leds better then what the fujic stuff did . iused the 20mm star since it was cheaper then the 16mm for some reason

bought the u3 from fasstech https://www.fasttech.com/products/1189702

Nice work Shaquille! That’s more like it. I might skip U3 though since I already have U2. Go straight to XM-L2 U2 on copper SinkPads. I just gotta pull the trigger on Emitters one of these days… :wink:

I finally got my lens and got nice results. Check it out -

Nice work Shaq!

Has anyone put XM-L2 U2’s in a TK75? Or are they selling that soon :slight_smile: ?

It would take a brave man and a very experienced modder to upgrade his TK75. I don’t think it would be that hard, but messing with such a well and high quality engineered light, with my ameteur modding skills it’s a no go for me….