Getting my feet wet in modding - Ultrafire Q5 & SK98

Flashlight Modding and DIY Parts
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Well when I joined BLF I was warned about two things. First was to prepare to open my wallet. Yeah, I found that out :bigsmile:

Second was that I’d be bit by the modding bug. Yeah, that seems to be what’s happening.

So here’s the deal, I’ve learned a lot here…but I still consider myself a novice. Just yesterday I ordered a Convoy S2+ and learned about the differences between 7135*3 / 7135*4 / 7135*6 / 7135*8. I learned how to calculate expected run time as well. As far as emitters I still haven’t the experience to know what is better than what. So I figure the best way to learn is to not only read but to do. With this in mind I have a few lights I’d like to start with (cause their inexpensive and if I screw them up then I’m not going to cry). Here is what I’m looking at to start with:

Ultrafire Silver 1200LM CREE Q5 LED Flashlight 18650 Zoomable Flashlight

This isn’t the ad or the seller but it looks just like the light in my hand right now that I got maybe a year ago. The second is this:

NEW 2000LM UltraFire CREE XML T6 Zoomable Zoom Focus LED Flashlight Torch Lamp

This IS the ad and seller. They haven’t arrived yet. I’ve have an SK98 already, put it on the end of my shotgun. For whatever reason I like these lights. The SK98 is bright, the silver Q5 doesn’t seem to be as bright as the SK98.

So these are really inexpensive, bargain basement lights. So I thought I’d try my hand at modding to get experience. For starters, I don’t know the sources you pros consider reliable (FT, BG, DX etc or someone else). So I’m all ears for suggestions, links etc that you feel are a good place for a novice to begin.

I’d like to make the silver Q5 brighter with a good run time. I’d like to make one SK98 as bright as is realistically possible without burning my hand or melting the light, the other SK98 I’d like to be bright but with a lean towards maximum run time. And looking for durability and reliability of course.

I appreciate your thoughts. :slight_smile:

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For the bright SK98, I’d suggest getting a XM-L2 or XPL (in your preferred tint) and get on a Noctigon copper star to reduce heat. You can get the LEDs already mounted from Richard at Mountain Electronics or Hank at International Outdoor. You’ll need the LED on a 20mm star.

You’ll need a thermal adhesive to stick the star to the pill. For a driver, getting a 3A Qlite with custom firmware from Richard. It’s a little more expensive to get custom firmware, but getting a driver programmed to exact way you want it with the exact levels you want, it will really make you love the light a lot more.

You’ll need a 17mm to 20mm adapter plate like this. Lastly, you could bypass the springs using silicone wire.

For the SK98 with max run time, simply using a Qlite with 3 or 4 chips should do.

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Excellent, thank you for the information and links. Time to do some homework!

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Alright, let’s see if I’m understanding this correctly (feel free to correct me if necessary);

For the LED and star:

CREE XM-L2 U3 1A LED on Noctigon XM20 V2 MCPCB

I noted this while reading the description;

I noted this is 7135*8 so it should really be quite bright on high. I also noted, per your post, that I can customize this driver with additional chips or I can reduce the number for a longer run time. So for the brighter SK98 project I
For the driver;

QLITE REV.A 7135*8 3.04A LED DRIVER - 17mm

could go with this driver and on the SK98 project that I’d like to maximize run time I can reduce it to your recommendation of 3 or 4 chips.

I also see where you can adjust the modes. Very nice option to have.

This adapter you’ve recommended is something that I’ve not seen so I’ll have to learn how it’s properly used.

I’m assuming that this will be quite a bit better than what comes stock in these inexpensive lights?

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You should check the pills of your lights if they can accomodate this much heat for higher currents (7135*8 driver). My Ultrafire SH-98 had a 11mm hole behind the star and the hole body isn’t the optimal thermal sink. It my be better (and runs longer) with 3 or 4 chips as recommended.

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Thank you for the suggestion :slight_smile:

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I’ve been playing around with the second light you list. Dedomed xml2 on noctigen, 3Adriver piggybacked onto 20mm board. The pill in these is more of a short collar, the space is limited inside so it’s a little crowded once the driver board is sat on the carrier board. The Led developed green/blue spots in places after only a short use at max, overheating probably, the body was very warm. Those cooling fins on the body are actually in the wrong place so by the time they see heat the top is well hot. Then the switch ‘collapsed’, possibly too much current? A pill upgrade (and better switch) might work, but the pill carries a groove for the focus collar o ring. The o ring needed replacing after a week. It needs to be thin, I stretched an already thin one over till it pinged into place, give yours a silicone lubing from the start. I’ll try to post pics tomorrow.

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Thank you for the tips, I look forward to your pics :slight_smile:

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That one shows the assembled pill sat on top of the body. Apologies for crap camera work, cameraphone. The pill is about two thirds of the length of the thin wall tube before the heat sink so the heatsink as i say is cosmetic… The ‘lens’ is a thin metal disc that pops out.

I dont know why its sayng moved or deleted. I’ll come back and check soon then upload second pic.

Or try this link? Photo of body.

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top

That pic shows the driver inside, the thin ledge the LED sits on. For dircet soldered transfer you would need to assemble from the bottom, solder LED base in, the solder in piggyback board. Hope these are some help.

Oh and i included what is left of the switch body for reference too :bigsmile:

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I have the SK98 (or SH98 from fasttech)
Reflowed a XM-L2 T6-4C on a 20mm sinkpad, epoxied it into the pill, (initially I build a special 20mm OSHPark driver by Texaspyro [that I also tweaked] but screwed up by not getting the resistor/capacitor orientation correct and ended up killing it, ran bright as heck until it killed the MCU, then I got a 20mm adapter plate and a 17mm Nanjg 105C 8*7135, and flashed with STAR firmware (that’s another critter you will get into surely :wink: , now it runs AWESOME and is incredibly bright!)

Hollow pills can transfer heat with good preparation, if you epoxy the star down to it w/ good epoxy (I use JB quickweld (it is infused with iron and has decent enough thermal conductivity) and once it’s bonded to the pill I take a bit extra and fill in the hole cut out where a solid shelf should be behind the star {the liquid epoxy before it sets makes a concave shape in the hole} [epoxy makes the bond permanent enough though (you can remove but takes ALOT of heat to crystallize the epoxy enough to crack it loose)]

Make sure you solderbraid/wire bypass the tail cap spring, that will allow better current to flow as it no longer has to pass up thru the thin spring, it has a nice thick wire for current to flow thru

Welcome to the madness of modding flashlights

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FT's unbranded SK98 is slightly cheaper and has a "Dealmetic" aluminum shim press fit over the older hollow pill as pictured here (left one).

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The Web links work and open the photos, yet the image links (taken from photobucket) don’t work. Sorry, till I get back on pc you’ll have to click the links…

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Copy the “direct link” in Photobucket and paste it between two exclamation marks: !!


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Still waiting for both the SK98’s to arrive (they’re passing through NY at the moment so with the weather lately I don’t know how quickly they’ll arrive). Looking at all the links in this thread (and thank you again). With the way the SK98 is designed would 7135*8 be okay (say on a 20mm Noctigon CREE XM-L2 U2 which I used in the F13 with good success)? As mentioned I’d like one SK98 to be very bright and the other maxed out on run time. But I don’t want the bright one to be so much that I’m burning my hand or melting something important. Would a 7135*6 be a better option overall or would the *8 be just fine in your opinion?

Thoughts welcome.

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Not all SK-98 are built the same. I would recommend to wait until you’ve got them in hand and can determine how good the thermal path is. I think SK-98’s are not the best hosts for high currents. One of the two I’ve got had a hollow pill, the other a big hole behind the MCPCB. For a zoomable light the SupFire F3-L2 for instance seems to me better built, there may be other hosts with zoom you can max the output much better.

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Both the SK98 clones arrived today (marked Ultrafire on one side and CREE on the other, link in the OP to the Ebay seller). Compared to the SK98 I purchased last year off Ebay (different seller), neither of these that arrived today are as bright. Neither seem to be as bright as my Sipik68 with 14500. And I used a couple of different 18650’s but they looked the same with either battery.

Took one apart. Took out the pill, my guess would be that it is aluminum? I tried to unscrew the ring that holds the driver in but can’t budge it. Do some manufacturers glue these in? I used my snap ring pliers but it just doesn’t turn. So this brings up a few questions;

  • If it’s glued, is there a good way to get it out without screwing up the pill?
  • There is a plate over the top of the pill where the LED and star are, how do you get that out? I don’t see any holes to use the snap ring pliers. Does it peel out?
  • Is there a better pill available that would fit the SK98? Perhaps made out of copper or do I need to stick with this aluminum one and make do?

Thank you :slight_smile:

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Could be glued; try a few seconds with a butane torch.

The plastic plate that’s usually over the top of the star can be prised out with a sharp pick;

The pill screws directly into the main body - just use a copper DTP star & you should be good to go.

If it’s a hollow pill like in Lightme’s picture above, you may want to consider fixing the star in with a little JB weld or something.

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Thank you. I have a Soto Pocket Torch and it worked. This is what was in the hollow pill. Like I said above, I wasn’t impressed with the amount of light it was putting out. Suppose to be an XML T6, is this what it is? Opinions on the driver? Still thinking of going with the suggestions above.

!http://s3.excoboard.com/forums/21042/user/218992/154747.jpg
!

Or is there a better pill that will fit?

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That's no T6, looks like an XP-E-type to me...

What's the diameter on the driver? Looks like it's about the same as the emitter. KD has a 20mm Nanjg 105E that might be a good alternative if you swap the emitter and beef up the heat sinking.

http://www.kaidomain.com/product/details.S023811

I'd install a new emitter on a copper star and fill the empty pill with some JB-Weld or something similar. Then drill out the through-holes for the wires. Install the 105E driver set to 2-modes and enjoy.