Inspired by Olight SR95 UT, I built a FM3X UT using P-bin CBT-90 (Even better than SBT-90 used in SR-95 UT, because that the CBT-90 is basically SBT-90 that came on on copper star).
I haven’t seen one of those Camo lights in a while now. Looks like it will be a great build. At least you don’t have to hold the drill with your foot any more! I like the thread in the tube, but I know just how thin it has to be. I don’t have the guts to try it myself.
Looks like it will be another great build. Waiting to see the rest. :bigsmile:
Thanks! The Drill Press certainly making it a lot easier than it used to be.
Also thanks for the tip on 35mm hole saw, works like a charm!
I decided to go with digital camo to match with my FF3, which came with a Ditical Camo carrying bag:
However, I realized that I can’t do the belly cutter style due to the digital camo,
as the patterns will not match at the joint, give away the “Cesarean” much more than that of a single color light.
Nice,I have been looking for the sbt-90 but can only find lower binned stuff,thanks for the cbt-90 info.I'm interested to know what driver you will use for this mod,9+amp drivers are tough to find and true specs are what counts.Love the mag mods and I am watching this post,you're off to a great start.
Got to love the weekends, got up early & got solid 4 hours of flashlight modding, like an addict just had his fix, I am a happy man
Started with modding Bright Lumens SST-90 heat sink.
Drill down the center post
Grind down the rim of post as well
Grind down the rim. I’ll be using using the heat sink backwards
Drill a dimple in the center of the rear to get rid of the center residue that’s raised slightly
Moving on modding the CBT-90
This is a beautiful Led, the cover glass over the die is actually AR coated.
Beefy copper heat sink is just a bit too big for mag, need some operation.
Cutting it with a cutting wheel took solid 2 hrs, because it need to be cooled down constantly.
Fits perfect in the rear of the heatsink, the well meant for driver circuit
For soldering the led, I chose 20AWG teflon wire. I also have 18AWG but that’s way too hard to work with, look how much thicker it compare to the 20G (Orange & Brown).
Did a quick test making sure the led is still working
Spread the arctic Silver, make sure to center the die perfectly & press down with the Mag Rebel SMO reflector (Quick focus stem was cut-off)
It’s a pity that after 3 years, there is still no 9A driver for sale with modes. there is one guy on CPF selling a 9A driver but only one mode. There are a bunch of SST-90 drivers from various stores, but none of them are true 9A.
In this mod, I am exploring the use of AW 3 level Mag D incan driver. The light will be powered by 4AA,
which would give 8.5A with Eneloops 2000 mah & probably over 10A using Elite 2000.
The AW incan driver is PWM, able to handle over 10Amp, combined with direct drive 4AA, I could possibly make my ideal hand held powerhouse.
There were some folks tried using AW incan driver on led, some worked & some didn’t. Some says it need 2 cells etc. I am not sure if this is going to work, but I don’t have alternative methods either. So here it goes:
Remove the Incan socket & supporting poles from AW Incan Driver/Switch combo:
The Incan driver does not label +/-, it’s necessary to test out which is which for led use.
Also, figure out how does it change modes. Looks like 4.19V, 4.18V & 4.09V for the 3 levels (Although they are PMW, there still a small difference in voltage as shown). Also, to turn it off, it need to press & hold the button, otherwise it’ll just keep switching modes.
I am guessing that this is a electronic switch?
OK, here comes The last steps:
Soldered up the switch to the led, put the switch & heat sink assembly in.
Applied Arctic Silver 5 for optimal heat transfer from heat sink to mag body.
Set the switch screw & locked it in place. Tested conductivity from switch body to flash light tail.
What else is there left to do? Put 4AA into FM battery holder & turn it on, right?
Well, it didn’t happen that way, I now have a bad news & a good news.
First, the bad news:
The FM battery holder I just got is missing a positive brass tab,
See the picture, the one next to the letter “P” is blank
Now, the good news.
I put a 26650 in there just to test the AW Incan Driver, It works! The 3 mode PMW switched the led modes perfectly, even the soft start works, it ramps up the brightness in a couple seconds.
This means that it’ll def. work with the 4AA, when I get the FM battery holder fixed, I’ll finally have luminex big chip led driven to 10 Amp with 3 modes
It looks like this will be one of those killer mods that will be referenced around the community. Thanks for taking the time to take pictures and do a write up/ walkthrough for us who are not so well versed in Mag lites and the options they offer.
Could you perhaps elaborate a little bit about this three mode driver that you use? I haven't even got a clue as to what i should be googling right now :-(
Can't wait till you get it done, I'd so love to see some beamshots?
It is quite expensive. It’s made by AW for high power incan D mag use. Because it’s PWM (Pulse Width Modulation, like the dimmer in your house, quickly turns a light on/off many times per second, the % amount time it’s “on” regulates the power out-put to achieve dimming.
Because it does not change the current at all, it can be used for providing modes on those situations
where there’s no driver available.
In the case of SST-90, CBT-90, SBT-90 lights, this will come handly, as the lack of high current driver with modes.
You can add modes with the AW switch to any light that is Direct Drive. In my case, 4AA battery direct drive the CBT-90, there is no current limiting drivers used. The AW switch simply provide modes w/o changing the current.
WOW, ma, that is a chunk of money. I had totally forgotten about that switch. I didn’t even realize AW was active any more. I’m out of touch.
Did you think of using 3 of the 8X7135 3040ma drivers, to get over 9A and use a Judco switch? Then you would have modes.
Yes, the AW driver is pricy, it’s the last resort for me as well.
I stacked 7135 up to 4.2A/3 mode before, but the soldering was a pain in the butt. I’d hate to do it again & stack even more 7135. LOL. Plus, in the case with 4AA/high amp, 7135 will drop out of regulation before even started. You will not get 9 Amp with a 9A 7135 stack. The 4AA Eneloop under high amp will sag to about 4 Volt & the CBT-90 under high amp, Vf will raise up near 4V. There is no room for any driver that requires voltage drop, I think 7130 needs about 0.3v voltage drop to stay in regulation.
However, it’s possible to do what you suggested in a bigger light. With a 9A, 26x7135 based driver,
It’s possible to use 2x 3.2V High current Lifepo4 cells as battery instead of 4AA & go up into 2D size.
With 4xAA, it’s a struggle to get above 8Amp without any driver in between. The AW high current Incan driver uses beefy 18AWG wires, there’s hardly any added resistance to get in between 4AA & CBT-90.
Does the CBT-90 have the + positive ground issue like their PT color cousins? If so is there anyway to use it for an advantage by directly mounting it to the heatsink with minimal thermal compound for maximum heat transfer vs using Articsilver as an electrical insulator thus lowering thermal transfer? Less heat = more lumens
It does, the copper pad is also the positive. But Bright lumen sink is anodized electrical insulating. You can use very thin layer of arctic silver
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Now, Finishing up fixing the FM Battery Holder:
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I made a copper washer with a tail, to be screwed under a nut the goes on the pole.
Unfortunately, the nut was originally glued & has crazy glue residue in the hole. I was not able to screw it on easy, after using excessive force, I broke that pole off & the nut won’t be able to go back-on.
The last fix. I drilled & tap a hole in the metal rod & used a small screw to secure the copper positive connection tab instead.
All these work just to add this little copper pad:
Voltage with 4xEneloop: 5.5V. 6.5A tail cap current.
Freshly charged up gets 6.62V 7.0Amp tail cap current
Voltage with 4xElite 2000: 5.2V 6.0A.
Elite 2000 supposed to be higher volt under load, in turn deliver higher amp than Eneloop.
This is a real disappointment. The Elite lasted about 5 min & died off. I think the batteries are shot, although they are freshly ordered.
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Beam shot vs. my Super Performing SR-51, which scored 58K lux (much higher than reported lux from older review lights). camera on manual. 1/10 sec. exposure 35 feet to the wall.*
Had to drill open the reflector hole a bit more to lower it for better focus.
Olight SR51 super performer: peak turn on –58K lux
Mag 1D CBT-90 UT peak turn on: –55Klux @ 7Amp
The tint on the US is snow white, not blue as seen in the Photo
The tint of SR51 is more green than the photo
The two lights looks similar in brightness, but I like the UT tint much better than the SR51.
