Jexree Mini mod V6 with XP-L V6 3D on DTP with 18awg wires & the bare MTN12DD board with *detailed* mod info

LED Flashlights – General Info 1 x AAA Flashlights
21

Encapsulating the qtc chip does sound like a real good idea. One thing I want to try (but it won't totally encapsulate it) is to use a copper disk that has 4 legs. The legs will go past the flat sides of the qtc (not the corners) into a plastic or fiberglass disk that will be about where the driver is currently located. The legs would have anchors on the back side of the plastic disk to keep the copper disk in place. Something that will kind of look like this (no plastic disk represented).

[_-----_]

Unfortunately, I have a bunch of Jexree Minis in every color. I bought them to be gifts, but the mode switching issues ruined that idea. I think I like the idea of just using the qtc to control output. All I really need in a light like this is moonlight and high. I don't mind if the qtc induces some resistance and limits high a little. I don't think I will use high all that often.

22

What a great idea for this light. It will be even more perfect for one of my modded ones ones because that one has a XM-L2 on copper completely direct drive without any electronics :-)

I ordered some too, thanks!

23

Cool stuff, I’ve used QTC in a couple of smaller twisty style lights that i modified to direct drive after mods gone wrong…
A Thrunite Ti, UltraFire UF-T1 and a DQG AAA - all have solid pills now with just the wires going through.

My method to keep the QTC material in place and free from torsional damage is to have the pill at the - battery end in the bottom of the tube, glued to a piece of cut out medium/low density compressible foam on 3 sides with a tiny amount of silicone or flexible glue.

The foam should be the same thickness as the QTC and a snug round fit. It’s not a good idea to have the pill centered as it can cause the battery to dent in the middle if you’re going for full twisty power.
Instead i keep it to the edge of the battery tube and trimmed like this.

This type of use requires fairly set tolerances on the cells used, I use Efest 10440’s with maybe a 0.5mm magnet if need be.

It’s like having mini fully variable RRT-01’s

:wink:

24

I am going to start a thread on my QTC driver , but it clearly cannot wait.

The principle is simple but the secret ingredient , found by accident , makes all the difference.And it is…a silicon oven mat!

Mark the centre and cut out a disc from the oven mat , say 10mm diameter and then cut out a QTC sized square hole in the

middle.Make 2 more discs from , for example , margarine lids , also with the square cut outs.Glue small strips of copper tape

to the inside of the insulation discs , one will be top , the other bottom.I then made up 2 QTC sized squares of copper from

flattened water pipe and soldered them to the copper tape so they act like button tops.Glue the 3 discs together , oven mat in

the middle and copper tape towards the QTC. I used superglue. Do not glue the QTC.

Last tip , on the QTC cut out in the oven

mat ,

scallop or bulge the straight edges of the mat so it and the QTC have room to squish , but leave the corners alone to securely

hold the QTC in place.The oven mat , or cake mould or oven glove or whatever you find , needs to be the same thickness as the QTC , mine was anyway.
The QTC is spiky zinc nano particles in a silicon matrix , so they squash the same.

My QTC’s have suffered no degradation , because they are isolated from the twisting motion.

Remember , the secret is in the oven mat :stuck_out_tongue:

25

This thread suffers badly from lack of pictures!

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^ Hear, hear. My imagination muscle is starting to get sore.

Look forward to your thread Billy X.

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Thanks djozz, this means a lot coming from you, i would never been able to do it so quickly without your prior mods on this, and everything else of great stuff you have done around here also, like all the testing the various emitter and mcpcb’s and more, you are a great inspiration for me.

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Guys i tried to take some beam shots, but i only have access to a phone camera and with no setting + i am really not a photo guy, i totally failed at taking some beam shots that show anything representative unfortunately.

@ImA4Wheelr, sorry to hear yours where messed up, on my the modes worked fine stock when on NiMH, but if you mainly want a great moonlight + when you need it a blast of high, your are going to love the QTC that kind of setup is easy to get, it is more complicated to get perfectly controllable variable setting in between, but with all the new great influx of good ideas from you, CRX & Billy X we will hopefully have that to soon.

@CRX, Billy X, ImA4Wheelr & djozz, thanks guys i am happy we finally get some really interesting discussions on the QTC here on BLF, i have wondered ever since i started reading here why it wasn’t used more on budget mods, i always thought it looked like it was made for this.

@Billy X, is this the kind of silicone oven mat you are talking about, or maybe this Where did you buy yours?

29

I try to understand how you did it here but i am a little confused, you say you have only a solid pill with wires going through, but then you say you have the “pill” at the - bat, do you mean the QTC here when you say that you have the pill at the bat -?

And where can i find 0,5mm magnets? for cheap hopefully, the lowest cost option i found yet is here but that is with crazy expensive uk shipping cost for some measly grams of magnets.
And on DX they have 0,8mmx5mm, but i think 5mm wide is a bit small at least when i tried with my 1,5mmx5mm they felt to small in width for the 4x4mm QTC.
How wide where your 0,5mm magnets that used in your 10440 lights?

30

Latest update on the mod.

I realized in my sleep (do you guys also dream about flashlights? ;)) that i hadn’t even tried to fit the plastic led protector under the reflector, because i thought it couldn’t possible fit now with the over 1mm thicker noctigon there, so i had some problem with the reflector shortening out the mcpcb if i used the top o ring against the bezel and screwed down the bezel as tight as possible, but as it was it fits the XP-L perfectly like it was made for it :bigsmile: and the o ring fits now almost also, the bezel don’t close for a fraction of a millimeter but even then it is better to have it that way because otherwise the looser bezel like to unscrew itself without the back pressure on the threads from the o ring.

And as a result of using the plastic lead protector, it improved the focus a lot, now there is much more of a hot spot :bigsmile: it is still not sharp how could it it is still a tiny tiny reflector, but the differences it makes is surprising, now when i use it in a dark room on max it is actually much more blinding because the eyes focus on the tighter much more intense hotspot, and my mind haven’t learn yet to treat it like a big flashlight and not shine on thing close up :wink:

I have to try to dedome a XP-L V6 1A on a future build in this light, i really wonder how it will look, my guess it will tighten up the beam considerably, almost like it had a larger reflector.

I checked flashlightlens.com and noticed they do not sell lenses in this size :frowning: the Jexree mini have a 1mm thick and 13,44mm wide lens, it is only their glass lenses that is that thickness, i wonder if it is possible to sand down a glass AR lens to the correct size? or will that damage the coating? i sent them a mail to ask if they have any options for me.

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I would say the first option looks closest.Mine came from a supermarket special offer-no longer available - and I got it for my oven and had to cut it down.I said it was luck.The main thing is to be the same thickness as the QTC (about 1.5mm?)
The second one says”silicone coated” at the start of the description , and “Material:Silicone” at the end.First one is surer.

32

I just got a notice that qtc order was cancelled due to being out of stock.

Looks like I might be shopping from some oven matts.

33

Thanks Billy, i will check around town first, if can’t find anything that that look to be the right thickness i take a chance on the first one then.

i tried to do a quick encapsulation with a soft foam and copper tape, but while it worked to protect it, i lost 2/3 of the out put somehow……? it became approximately like a NW Olight i3s on Efest 10440 ~280 lumens, and the foam was to soft so i got crushed way to fast.

So i wonder on your method Billy, do you lose a lot of output from DD or just straight QTC on the bat?
And have you experimented on if a lighter or thicker thread grease give better control of the QTC variability? or is it good enough as is, which lights are you using it with by the way?

34

@ImA4Wheelr, You can buy QTC here also, near the bottom of the page.

And here smaller pack

35

Thanks cajampa. Shipping is kind of crazy though. $9.50 for one qtc and then $2.00 extra for each additional qtc.

Man, I think I read people were getting these for like 15 cents each a few years back. Maybe I misread.

36

If you are talking about lessemf’s shipping, they are usually accommodating, just email them and i hope they can provide some saner shipping on those tiny QTC, i have ordered some items from them in the past and the shipping calculations in the store is negotiable and i think they have more options available, i don’t think their web shop really handle different weight very well.

Just ask for the cheapest shipping with no tracking or maybe if they can just put them in a bubble mailer or something like that.

37

I tried different foam densities initially and did not get anywhere.The silicon mat was what stabilized it.
I have used it in a 16340 clickie Cree 10B .I left the driver in initially and put the QTC pill in series and cut down the tail spring.
Two threaded parts , head to body and body to tail , gives much more sensitivity , I think.It was not DD because the original driver was still there , but it seemed as bright on high with the QTC as without.I say was because I tried to make a test torch out of it to measure current , Vf and resistance across the QTC.16340 bodies are too small to drill holes through the threaded section to pass wires .RIP :frowning: I have an 18650 host waiting now.
I can confirm having seen over 10kilo-ohm across the QTC while getting useful(100= lumens) out.Should not be possible , but the inventors got the same!

38

Thanks for the info Billy, sorry that you broke the light trying to further your understanding of the QTC :frowning:

Yeah i noticed that on the Jexree mini have also two threaded parts , head to body and body to tail, i have thought about if a less stiff spring could give a smoother ramping…….it is a lot of things one could to try.

Ok the more i think about it the more a silicone mat buffer around the qtc sound like a good way to do this, even better could be a large cut able piece of QTC to fit, the problem is without some buffer to give the QTC some mass to withstand the force on it it just to easily get overpowered and you get max instead of that nice variable smooth advancing on the power output.

39

Hi, i meant that i have filled the pill that the LED is attached to completely with a JB weld/SiC mix and it now only has a positive contact going through it to the battery, no driver at all. When i spoke of the pill at the - battery end i was referring to the QTC material.

I’ve used this seller of 0.5mm magnets before, various sizes. I use 4mm for battery + and 10mm for battery - .
0.5mm magnets do seem to be more expensive than others, try 1mm magnets if you can, i only used 0.5mm because of the tiny flashlights i was working on.

http://www.ebay.co.uk/itm/10-25-50-Strong-Neodymium-Disc-Magnets-4mm-5mm-6mm-8mm-dia-x-0-5mm-1mm-2mm-3mm-/161559837923?

40

Thanks CRX, i will buy some of those magnets to test then.

Update
I tried to build some different buffers to hold the QTC. but while it worked to make it wear less on it and give a smoother ramping, every time i lost a lot of lumens :frowning: so i still haven’t found a way to secure the QTC and not lose way to much.

Flashlight lenses didn’t get back to me, i am a little disappointed after i have read that they have such great customer service………

So i searched kaidomain.com and found 2 possible candidates as upgrade lenses, the biggest that will fit in the jexree mini is 14mm and maybe it is possible to use something as small as 12mm because the bezel is a tiny bit smaller than that, so the o ring should hold it in place, i hope anyway.

The stock is 13,44mm x 1mm, and these are the ones i think i will test
13mm x 1.0mm Water White AR
Multi-Layer Coated HD Flashlight Lens 12mm*1.5mm