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

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DENGOH
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That is cool. Just to highlight potential scam especially flashlights not performing as it should be.

cool i'll see you when you get there

Pok
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BTU problems :

1.Heat sag >>> IMO BTU transfer heat better than TK75
2.Battery voltage sag >>> Yes, 3.8A to LED while Vbat load about 3.5V+- and Vled about 3.4V+-
edit : plus Vdrop at Circuit and resistance at tailcap switch, springs (That why I like BTU with 4×18650s)
-IMO solder wires to springs to reduce resistance, I did almost my flashlights
3.IMO BTU is really U2

4.REMEMBER that Reflector(TK75 is better ) and lens(not AR) cut off OTF 5-10%

rdrfronty
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I know I just last week I got a couple C8’s modded with XML U3’s. 3.8a drivers mounted on brass pills. Tailcap reads about 3.74a range on both lights with the same 3400mah protected Keeppowers. Both lights tested yesterday right at 960otf after 30sec. That is exactly what the BTU does – 960otf per U2 = 2880otf = the exact number we got. So yes I’m confident the light has U2’s and is performing just fine.

DENGOH
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Since most owners are convinced heat sag and LED bin are not issues, then it might be 3*18650 and reflector and lens causing lower OTF. These three things are picked up before but claimed to be not an issue. But now it has high potential to cause BTU not performing. If possible, I suggest to do things below before testing to see real performance of BTU:
1.Use 3 good unprotected batteries
2.Solder wires on spring
3.Remove the lens

cool i'll see you when you get there

rdrfronty
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DENGOH wrote:
Since most owners are convinced heat sag and LED bin are not issues, then it might be 3*18650 and reflector and lens causing lower OTF. These three things are picked up before but claimed to be not an issue. But now it has high potential to cause BTU not performing. If possible, I suggest to do things below before testing to see real performance of BTU:
1.Use 3 good unprotected batteries
2.Solder wires on spring
3.Remove the lens

BTU not performing” – you do understand the difference between the two lights is less than 1.6 %????? That’s like saying a single xpg cr123 light running at 288otf because your friend has one that does 292otf. Seriously, do you think even name brand ANSI lights don’t vary more than that? I KNOW they do. I’ve tested 50+ lights for a total of perhaps 3-400 lumen tests. Any given light will vary more than that from one test to the next.
The BTU is performing properly. The TK75 is performing properly. Both are dead on for what U2’s should be doing at the amperage they are driven at.
Dale
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Group Hug!!!

atbglenn
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Dale wrote:
Group Hug!!!

I love group hugs! Everybody take a deep breath and just chill. 

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DayLighter
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and don’t forget.. with TK75.. you can have extra extension tubes ( up to total 9 but fenix recommend only 2 tubes) for longer running time ( come in handy for search and rescue mission) Smile

The only way to do a great work is to love what you do.

rdrfronty
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Sorry guys, I’m trying to not get worked up. I started this thread trying to show what both lights can do, good or bad. I feel both have their pluses and minuses. I think anybody with either one in their hand will be very impressed with their performances. I am obvious a BTU fan, and believe me it hurt to post up that the TK75 had the slight edge in peak output. I was trying to be as unbiased as I could. I knew going into this thread the TK75 might pickup more fans. What I didn’t expect to see is people trashing an great performing light like the BTU. Having favorites and opinions is normal human nature. That’s one thing that make forums interesting. But attacking a light, with incorrect accusations, by someone who doesn’t own and has never even seen the light, is just wrong.
Saying the BTU its too heavy, saying it should have 4 batteries, that it should have AR lens, that it’s ugly, or needs a side clicky – those are all good and proper opinions that others have stated. And thats all fine – those are opinions, popular ones at that. But I can say also say the TK75 feels a little flimsy, doesn’t have deep enough reflectors, should throw further, has too low of a high, has weird two button controls, etc. But those are just my opinions.
However falsely staing that the BTU is under performing – that does ruffle my feathers because I know the statement is not true. Does my brothers TK75 have slightly higher output than my BTU – yes. That’s a fact. It’s also a fact that my BTU performance of 2880otf, obtained with 3ea 960otf , 3.8a driven XML U2’s, are well with in the proper output for a normal, decently heatsinked light.
Ok little rant over. Now I’ll group hug (can I step on Dengoh’s toes while doing it though? ). It would make me happier Smile

rdrfronty
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DayLighter wrote:
and don’t forget.. with TK75.. you can have extra extension tubes ( up to total 9 but fenix recommend only 2 tubes) for longer running time ( come in handy for search and rescue mission) Smile

Yes that would make for impressive run times to say the least. Only negative there is it would make it pretty big, about like the TK70 or bigger. I would think just taking the TK75 as is, along with spare batteries would be more practical for long journeys with it. You would still get the long base run time with the 4 starting batteries, could swap out fresh runs if the time required it, but it would allow you to keep the light weight and compact size that is one of the TK’s best features. I would hate to carry around a TK70 sized light for hours on end. I say that knowing my similar sized SR90 would get pretty cumbersome too after a bit of time lugging it around.
But irregardless, it’s nice of Fenix to give you that option of battery extensions if so desired.
manxbuggy1
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My brother and I both have slightly different takes and views on these lights like everyone else does but we just agree to disagree. I personally find the ergonomics and looks of the TK75 to be more to my tastes while he prefers those of the BTU. I would not trade my TK75 for his BTU or most any other power light out there. I have been watching the thread on the RC40 with a little interest but personally think that even though it should be a beast it also looks like a beast (kind of homely). I don’t think the BTU is ugly by any means. It is a little big for my personal tastes but I am glad my brother has one so that I can play with it too. Even thought I like my Tk75 better I challenge anyone to pick up a BTU in CW and shine it around a while without getting a big smile on your face. Betcha can’t do it. Lol. Smile

ILIKEFLASHLIGHTS
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The RC40 is going to be a heavy flashlight to carry at 3lbs 4oz. That’s even heavier than the TK70. And the price has yet to be seen.

I don’t have a BTU Shocker, nor can I say I really want one. The TK75 does more than I need and it’s a lot smaller and lighter to pack. I also would bet money that the quality edge would go to the TK75 no doubt. The TK75 is just a more practical light.

chrisc
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Great review. I’ve just bought a tk75 and it was a hard choice. I almost bought both as I like them both so much. The tk75 was cheaper and I like the size of the tk75 more than the btu.

They both get great reviews and I’ve decided that if I was to go for something as big and bulky as the btu I’d probably grab a big headed hid. I’ve got a tn31n for throw so at the moment I have no real need for much else.

manxbuggy1
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Well hopefully next week or two we can do some head to head beamshots. Maybe by then rdr’s TN31MB will be in and we can do some with it as well. Of course as far as throw goes it will be in a class by itself. The Skyray king is a nice flooder and might be interesting to campare to these other big flooders.

lionheart_2281
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manxbuggy1 wrote:
Well hopefully next week or two we can do some head to head beamshots. Maybe by then rdr’s TN31MB will be in and we can do some with it as well. Of course as far as throw goes it will be in a class by itself. The Skyray king is a nice flooder and might be interesting to campare to these other big flooders.

A comparison to the SRK is always a good idea when comparing flooders as it’s such a common torch and most people know by now what they are capable of.

Chicago X
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lionheart_2281 wrote:
 It's seems to me the BTU hasn't really lived up to its hype, anyone else feel that way?

Nope.

Not even close.

http://wardogsmakingithome.org/index.html

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C-channel
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I wonder what warrants the pricing of the BTU except for exclusivity. The performance to TK75 is so close. I have had great CS with Fenix and I believed its a trusted brand.
With their experienced RND and excellent circuit design. I believe the TK75 is the light to go for. Now I need a holster.

How bright is bright enough...

Runtime VS Lumens...

DENGOH
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rdrfronty, thanks to you for your unbiased test result. We definitely need more people like you who are willing to measure and report.

From reading your lines about testing many other flashlights experiences, just want to know is it your stand is that your BTU is not the best performer among other BTU, while your brother’s TK75 is the best performer among other TK75, this cause your result showing TK75 has equal lumen output with BTU at 30s.
We can’t just ignore the fact BTU is driven 3.8A per led, while TK75 is driven below 3A per led, both are U2, if everything is perfect, BTU should have higher output, right? But nothing is perfect.

cool i'll see you when you get there

Spasmod
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One thing to bear in mind is that rdrfronty said near the start of this post that the BTU has a ‘bigger flood’ AND more throw.

If you take into account the extra flood then overall it seem the BTU is performing exactly as it should and not ‘underperforming’ at all

DENGOH
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Spasmod wrote:
One thing to bear in mind is that rdrfronty said near the start of this post that the BTU has a ‘bigger flood’ AND more throw.

If you take into account the extra flood then overall it seem the BTU is performing exactly as it should and not ‘underperforming’ at all


We are talking about total output at 30s here.

cool i'll see you when you get there

brad
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Dale wrote:
The pics suck though… ( 2 much beer ) !{width:100%}http://i1252.photobucket.com/albums/hh571/ajones1051/GEDC0042_zps51fa0e9...!

We are allowed to drink beer while operating high powered flashlights?

Not what we have but what we enjoy, constitutes our abundance.

atbglenn
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brad wrote:
Dale wrote:
The pics suck though... ( 2 much beer ) !{width:100%}http://i1252.photobucket.com/albums/hh571/ajones1051/GEDC0042_zps51fa0e9... We are allowed to drink beer while operating high powered flashlights?

yes, and heavy machinery as well  

Boycott Nike

rikr
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atbglenn wrote:

brad wrote:
Dale wrote:
The pics suck though… ( 2 much beer ) !{width:100%}http://i1252.photobucket.com/albums/hh571/ajones1051/GEDC0042_zps51fa0e9...!
We are allowed to drink beer while operating high powered flashlights?

yes, and heavy machinery as well  

+1 Big Smile :bigsmile: Wink

 

 

 New Collection / Old Collection

 
atbglenn
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rikr wrote:
atbglenn wrote:

brad wrote:
Dale wrote:
The pics suck though... ( 2 much beer ) !{width:100%}http://i1252.photobucket.com/albums/hh571/ajones1051/GEDC0042_zps51fa0e9... We are allowed to drink beer while operating high powered flashlights?

yes, and heavy machinery as well  

+1 Big Smile :bigsmile: ;)

Rick, and when I've had way too much to drink, I like trimming my hedges with my lawn mower

Boycott Nike

rikr
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atbglenn wrote:

rikr wrote:
atbglenn wrote:

brad wrote:
Dale wrote:
The pics suck though… ( 2 much beer ) !{width:100%}http://i1252.photobucket.com/albums/hh571/ajones1051/GEDC0042_zps51fa0e9...!
We are allowed to drink beer while operating high powered flashlights?

yes, and heavy machinery as well  

+1 Big Smile :bigsmile: Wink

Rick, and when I’ve had way too much to drink, I like trimming my hedges with my lawn mower

Glenn, That’s bad!!! hehehehe Big Smile

 

 

 New Collection / Old Collection

 
rdrfronty
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DENGOH wrote:
rdrfronty, thanks to you for your unbiased test result. We definitely need more people like you who are willing to measure and report.

From reading your lines about testing many other flashlights experiences, just want to know is it your stand is that your BTU is not the best performer among other BTU, while your brother’s TK75 is the best performer among other TK75, this cause your result showing TK75 has equal lumen output with BTU at 30s.
We can’t just ignore the fact BTU is driven 3.8A per led, while TK75 is driven below 3A per led, both are U2, if everything is perfect, BTU should have higher output, right? But nothing is perfect.


The TK75 isnt driven at under 3a per emitter. No way. You don’t get 975otf at under 3a with a U2. Not gonna happen. At the emitter – sure, not otf. Possible put on a big slab of copper it might come close, but not in a triple led setup in a under $200 light like the TK75. It’s not gone to happen. The TK75 is driven somewhere in the 3.5-3.8a range. I’ve got U2’s and U3’s driven just slightly over 3a and they fall about 100otf short of that. I’ve got U3’s driven at 3.75a on copper pills that are almost there with about 960otf at 30sec.
But U2’s, triple setup, UNDER 3a per LED, in a factory setup, putting out 975otf each – nope.
warmurf
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lionheart_2281 wrote:
DENGOH wrote:
atbglenn wrote:

Dale wrote:
lionheart_2281 wrote:
God the BTU is such a big, ugly, heavy light…
It’s a MANLY light to be sure! Anyone with a limp wrist can purchase the 75 as to not injure their delicate nature…. Bwah ha ha!!!

I guess I’m limp wristed. Not even close, I prefer the TK75

I am 74kg and I can bench press 75kg 10 times. Everyone should try this, bench press just over your own weight, to know are you really strong.

The AVERAGE person can bench 90% of their body weight, if you fall below the average perhaps it’s time to get to the gym!
Seriously though, why would anyone choose the BTU over the TK75? It’s seems to me the BTU hasn’t really lived up to its hype, anyone else feel that way?

I’m 146kgs. Guess I’m in the other 10% bracket.

How long does the BTU run of high before it’s too hot?

rdrfronty
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warmurf wrote:
lionheart_2281 wrote:
DENGOH wrote:
atbglenn wrote:

Dale wrote:
lionheart_2281 wrote:
God the BTU is such a big, ugly, heavy light…
It’s a MANLY light to be sure! Anyone with a limp wrist can purchase the 75 as to not injure their delicate nature…. Bwah ha ha!!!

I guess I’m limp wristed. Not even close, I prefer the TK75

I am 74kg and I can bench press 75kg 10 times. Everyone should try this, bench press just over your own weight, to know are you really strong.

The AVERAGE person can bench 90% of their body weight, if you fall below the average perhaps it’s time to get to the gym!
Seriously though, why would anyone choose the BTU over the TK75? It’s seems to me the BTU hasn’t really lived up to its hype, anyone else feel that way?

I’m 146kgs. Guess I’m in the other 10% bracket.

How long does the BTU run of high before it’s too hot?


Truthfully I don’t know. I’ve generally used the BTU’s turbo in lots of short bursts of under 1 minute. I know even while doing a lumen test in my lightbox with foam around its head (for light sealing) the light isn’t remotely starting to heat up in those 40 sec or so. The head isn’t warm at all. And I don’t feel it’s due to lack of heatsinking because the lumen output levels off very nicely, with only a slow drop after about 5-10sec.
I wouldn’t hessitate to run it on turbo well after the 3 min. kickdown. Kicking back on multiple times would likely be ok. Thats one place this lights big beefy body helps by lots of mass to absorb the heat the LED’s generate. I do need to experiment more with longer runtimes and see how it does.
DENGOH
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rdrfronty wrote:
DENGOH wrote:
rdrfronty, thanks to you for your unbiased test result. We definitely need more people like you who are willing to measure and report.

From reading your lines about testing many other flashlights experiences, just want to know is it your stand is that your BTU is not the best performer among other BTU, while your brother’s TK75 is the best performer among other TK75, this cause your result showing TK75 has equal lumen output with BTU at 30s.
We can’t just ignore the fact BTU is driven 3.8A per led, while TK75 is driven below 3A per led, both are U2, if everything is perfect, BTU should have higher output, right? But nothing is perfect.


The TK75 isnt driven at under 3a per emitter. No way. You don’t get 975otf at under 3a with a U2. Not gonna happen. At the emitter – sure, not otf. Possible put on a big slab of copper it might come close, but not in a triple led setup in a under $200 light like the TK75. It’s not gone to happen. The TK75 is driven somewhere in the 3.5-3.8a range. I’ve got U2’s and U3’s driven just slightly over 3a and they fall about 100otf short of that. I’ve got U3’s driven at 3.75a on copper pills that are almost there with about 960otf at 30sec.
But U2’s, triple setup, UNDER 3a per LED, in a factory setup, putting out 975otf each – nope.

Someone have already measured TK75 using power supply, at 7.5V, current draw is about 4A. That is 30Watt. If it is 100% efficiency which is impossible, each LED get 10Watt. XML driven at 3A typical voltage is 3.35V, and that is about and above 10W. So no way TK75 is driven above 3A per led. Based on this and runtime, I estimate it is 2.8A per led. XML maximum limit is 3A, no way a reliable brand like Fenix will drive it above 3A. Fenix will prefer to make it perfect in heatsink, and drive it below 3A. That is what has happened in TK75. Fenix is always playing safe. TK70 is 2.5A per led. With smaller head, it is not logical for Fenix to drive TK75 to be 3.5A per led.
About your last line about 975otf per led, maybe you have overestimated the otf. Fenix official number is 2600 lumens, that is way too low compare to your number.

cool i'll see you when you get there

Chicago X
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The TK75, while impressive, cannot bend the laws of physics.

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