Review: Crelant 7G9 (XM-L U2 | 3 x 18650)

But he is saying it will run on only 1 battery, not 3. He said he can't get that special driver to handle 3 batteries in parallel.

Ok - he cleared up the issue of the batteries - looks like 3 will be ok afterall. I'm going ahead with the Vinh mod - sounds like 4.3 amps, or in that ballpark. He recommended no mode memory, always comes on in high which I prefer, with the mode sequence of:

High, Medium, Moonlight, High, Medium, Moonlight, 10Hz Strobe, 2HZ Blink, SOS, Beacon

This will be ideal for me - got the fancy blinky modes but never have to see them if I don't care to, but, I can get to them if I want. 99% of the time I want it to come on high, so this will always default to high without mode memory. Sounds like he will retain the forward clicky, which is also fine with me. Shipping it out tomorrow - can't wait to see this thing...

Mark is selling this light now for 80.99….biggest drop I’ve ever seen in such a short time on a light. Uggh!

Yes - $81 is what I paid on an eBay bid a while back, but I had vinh mod mine - very pleased, nice UI for a fwd clicky, lots of modes but no mode memory, which is fine. Crelant is launching a bunch of lights with U3's and variable brightness with a side switch - a new 7G9 is due soon I bet.

of course, I understand that when a new line is introduced the previous models get reduced, but this light entered the market last June - less than six months ago and the price has been reduced by over 40%. I paid @120.00 and thought that was a good deal.

Between the loss I suffered on this light and the Thrunite’s (TN30 and TN31) I’m beginning to think I should buy a new light only after waiting six months after it’s introduced!

Then again, most lights don’t seem to go through such massive price reductions, let alone in less than six months.

Oh, well. Live and learn.

Yes - agree, that really bites and it was really fast - Crelant and ThruNite are trying to keep up with the technology and upgrade their offerings. ThruNite is already up there but Crelant is striving to be there and appears to be working aggressively in R&D. I don't know how they can justify such large discounts though.

I'm generally working from the other end - cheap lights I'm upgrading, but by the time you upgrade the LED, driver, button, lens (plus all the tools, $$$ epoxy, grease, etc.), you are up in the range of the expensive lights, but without the body/pill quality. But I do have fun .

Just a suggestion:


Face-up view of a circular SS cap resting on 3x18650s without shorting. The center portion of the SS disc is left to be thicker and of diameter corresponding to the recess of the PCB.


Face-down view with a 15mm disc magnet to confine the 18650 heads.


15mm disc magnet stabling the 18650s.


A side view to show the arrangement.

The above is not for the heart-fainted. Please refer to post#11 of:

Has anyone figured out how to access the emitter and the driver on the 7G9? Mine is needing some tweakin. I know Wayne (vinh) knows how to do it, but didn't want to bother him yet on this. Not sure how to get past the glass on the front end, or how to get access anywhere on the backend (battery + side).

I believe some models have the back and front glued together. If this is the case, some elbow grease, caution and patience will be required. While I have not removed my top cover I did manage to unglue the end part and mod the clicky.

Just received it 2 days ago, and the tailcap rubber came off within a few minutes of ownership … and the only way to put it back in properly is to remove the tailcap end of the flashlight!

Well I’ve tried boiling the whole battery compartment (sealed in plastic bag of course) for almost 10 minutes, then on another occasion tried freezing it for a couple of hours, and on numerous attempts used vice grips and also strap wrenches … and NO luck!

Crelant’s obviously used more than just loctite on some of these - I’ve also read of similar reports by some CPF members.

About the Driver - I’ve read of someone drilling a couple of holes into the positive contact plate (battery side) then pulling it out with pliers or something to access the driver!! Of course you’d need to be careful not to damage the contact plate … unless you have a source for replacing it.

Good luck

Ahh, ok - that's what Wayne (vinh) must have done to mine (and others). I, just a couple of hours ago, was able to remove the contact plate (was simply pressed in), and got access to the driver. He must have drilled first, then after removing it, cut the contact plate back on 2 sides. He stripped all the components off the contact plate, backside (this is normal to use the old driver as a contact plate), and added a KD V2 driver, looks like, with 4 extra 7135 380's, so total was 4.52A -- think this is way too much, though at the time I asked for that, not knowing then what I do now.

The problem I'm having is the brightness drops significantly in the first 3 minutes it's on - ceiling bounce test shows it goes way down, from 170 to 90 lux. I suspected this was happening all along but didn't measure it until recently when I got a light meter. I thought the cause was the over-driving at 4.5A, so I reduced it to 3.8A -- but brightness still drops.

Next thing I don't like is the driver was simply suspended in air, with a ground wire going to the brass housing interior, and the driver wrapped in duct tape to prevent shorting on anything. Also, the driver looks previously used w/solder all over the edges, solder splashes, etc., so my plan is to replace the driver, add a sanded down brass pill and solder it inside the brass housing - this will give the driver a full proper mounting with a good ground and heat sink, and still use the old contact plate/driver to provide the battery + wire.

If the driver fix/mount still doesn't work, must be something to do with the LED, but still don't know how to get to it. Can't get past the lens and I don't even see anything that could be glued - the lens appears to be behind a ridge, so seems like no way to get it out from the front...

I reckon the driver is the culprit mate! Being suspended in air and wrapped in duct tape is very amateur work - not only is the driver not heatsinked, but the duct tape is trapping the heat in!! Very disappointing workmanship … and interestingly, I bought a custom XR-E pill from that same modder that also looked previously used, with messy soldering and splashes on it.

All the best with your driver upgrade / fix Tom … I’ll try the same thing with mine when I get a chance.

Cheers

[quote=d337944]

Hhhmmm, oh boy, I was trying to justify this, but I guess it sounds bad, but that's what it is... I know he knows what he's doing, maybe he was just rushed and short of parts at the time...

I'll find out soon enough if it's the driver - working on it tonight, may not be able to finish it this evening though.

Will it work with 2x18650?

Yup, it even works with 1x18650, although there is a very slight decrease in output.

Hey Tom, mind taking some pictures of the insides?

I’m having some difficulty getting the driver out… or disassemble the head in the first place.

I’m not even sure where to twist, as it seems to be epoxied pretty well. :slight_smile:

Sure! Wife's birthday today. gotta run to get her something , hope can post some soon. For the head, I can't get past the lens. For the driver, they drill one hole on each side, opposite each other, of the + contact board, outside the brass ring. Once you do that, you can get more leverage (screw driver in the hole, applying force to pry it up, etc.), but I'm not sure about it being soldered or epoxied - mine looks like it was maybe soldered (don't know how they could have done that, unless it was done on my modded light later??).

Thanks for your reply! Take your time with the pictures, spend some time with your loved ones. :smiley:

Drilling a hole in the driver board sounds slightly scary to me. :stuck_out_tongue:
Although I’ll probably do that eventually, for now I’ll continue to pry it and try to loosen the threads on the head.

Cheers!

Good to know, thank you very much :wink:

I have another thoughts, would like to know if I’m right (know very little about this): lets say we have flashlight that works with 3 batts in parallel, 5A on HI. So, as far as I understand, if I insert 1 batt, it will work well if that batt is IMR o very good ICR, right (to provide 5A of current)? If I’ll try it with 2, it will be 2,5A per batt, right? (and 1,66A with 3). Thanks.

I'm pretty certain that's correct. The circuit, say, is designed to draw 5A. For batteries in parallel, the voltage remains the same (up tp 4.2v), so, it draws 5A and if there's 1, 2, or 3 batts, it should just split the load. I've been testing the 7G9 with just 1 battery to verify the amps drawn from the batteries. For 5A, single battery applications, you have to have a quality battery that can produce that amount of current for a period of time. With 3 batteries, it's not so crazy of a draw per battery and you get a longer run-time of course. The 7G9 is the same as the SRK in this respect (i.e. parallel wired batteries), though you are driving 3 LED's in an SRK. In a 2 or 3 cell serial battery setup (end to end), you add the voltages of the batteries, so for 2 batts, the voltage output can be up to 8.4 volts -- most of these drivers are designed for up to 9 volts I believe.