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Modifications => LED Flashlight Modifications => Topic started by: 18sixfifty on November 02, 2015, 03:07:09 AM

Title: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 02, 2015, 03:07:09 AM
Well I haven't posted any of my mods for a while but I thought I would share this one. It's an older light revisited with a new driver and side switch installed. It's basically a; "How to turn your over-sized unwieldy plunger light into a more user-friendly beast".

You can do this with pretty much any of the multi-emitter plunger lights.

For a driver I use the Ultra low resistance FET Direct Drive driver. Like this one. Make sure it's the zenor modded one.

What I do is simply hang the new driver off of the remains of the old driver. I wipe the old driver clean of parts and then drill two holes through it. One right in the middle where the spring goes. (Take the spring off first). Then another hole next to the side. Take some heavy gauge wire and go through both holes. The positive wire goes through the center hole to the top of the spring. The negative wire goes through the hole and is soldered onto the negative contact on the top of the old driver.

These two wires are then wired to your FET DD drivers contact points. This leaves the new driver suspended in air under the old driver. Why do it this way? One because it's difficult to find a driver that fits perfectly into all of these older lights and second because it's BETTER to have it suspended in air where the driver itself will not be picking up heat from the light when it becomes super hot. If you are worried about the driver overheating you can always simply POT the driver itself after you have everything wired up.

Now on this light I soldered 6 18 gauge wires to the new driver to go to the emitters. Three of them are soldered to the top positive spot right next to where the positive wire is already attached for the spring. So you have the wire from the spring attached to the driver and three other wires now attached to the same spot on the new driver. The other three wires are soldered directly to the negative pad on the FET.

Ok why six wires? The plan is to use 2 batteries not 3 batteries. If I was using 3 batteries I would have used only 4 wires. The goal is to have ONE battery per emitter wired in direct drive.

So with 2 batteries the emitters are wired 2S3P with 3 batteries it would be wired 3S2P

What if you have a 12 emitter light?

Well the Parallel wires always have to match the number of batteries. So it goes like this.

2 batteries =  2S6P  3 batteries 3S4P  4 batteries 4S3P

What about 9 emitters? Well then you are stuck with 3 batteries. So it's going to be 3S3P.

15 emitters? 3 batteries  3S5P  See how the series always matches the number of batteries? This will always leave you with each emitter being driven by a single battery. If you were using a single battery (or multiple batteries in parallel) for a 12 emitter light it would be 1S12P. 

How about addballs like 5 and 7 emitter lights? Well then the FET DD driver isn't going to work.

Also keep in mind that this is for XML or XPG emitters that can handle full power from a battery. The math is different when it comes to XPE or MT-G2/XHP emitters.

If this makes no sense to you, just drop me a PM and I'll draw you a picture of how it works for any light you have.

Now that we have all that wired up you still have to wire the side-switch. Actually you can do this first to make it easier but half the time I forget so it works either way. The switch is wired to a negative spot on the new driver and the second post on the MCU, some of these drivers have a spot for this others don't.

For a switch I use a simple momentary Horn Switch, they cost a couple bucks and can be picked up at just about any electronics store or on-line for less.

I just use a regular old hand drill starting with smaller size bits and working my way up until the switch fits in snugly.

This was an old light and I didn't feel like putting too much money into it, so I simply used the old emitters they were XML U3 from fast-tech they have a lower vF so they actually work really nice in this light. I de-domed them and re-flowed them onto noctigons.

When trying to properly set the emitters in place there are few tricks that I use.

After you have removed the old emitters put the reflector back in without the lens in the way. Then take a marker and reach in through the reflector and mark where the emitters go. This way you will know exactly where each new emitter is supposed to be. Then when you are putting the new emitters in place put the reflector and lens/bezel back on with the centering rings on the emitters and the thermal paste/epoxy on. Always put the entire head back together while it dries. Once it's dried you then know that each emitter is exactly where it's supposed to be. If you don't put the light back together while it dries they are not going to be where you want them.

Another trick is to think ahead before you place the emitters in. Keeping in mind where you want to place your wires so that they will not be crossing. If you set it up wrong and need to cross wires over wires you might find that your reflector will not sit down properly. You will probably need to drill new holes for your new wires. Again think ahead so you know where the wires will be coming up from.

Now you have the head with the holes for your wires drilled, then put the emitters in place, the way I posted above.

 After your emitters are dried in place pull your wires through the proper holes, put the driver in place and pull your wires up through the holes as far as you can.  (At this point I strongly suggest that you test everything to make sure it's working.)  Then snip the wires so that they are as short as possible and solder them suckers up.  Snipping the wires after you have everything in place (And working) allows you to keep the wires as short as possible. The key to max lumens in these lights is using as heavy of gauge wire as possible and keeping it as short as possible.

Sorry I didn't take pics of the process but I really wasn't thinking about it at the time.

Maybe in your minds eye you can picture what it's like.

Old driver/contact board. Wires through it to spring and negative contact point. Then the new driver suspended from that with six wires through the head wired to the emitters. None of these wires ends up long at all this way and the driver is sitting in air held in place by the heavy wires between the old driver and the top of the head.

Lumens were a very nice 7,000 at startup and settled in at 6,200 after thirty seconds. The Lux was 172kcD.

I'll attach some pics in a bit. 

Oh and just for the cheapskate in me I'll mention that this mod cost me right at $10 to do. I built the driver myself so that was about $3 in parts and the six noctigons where another $6 wires and solder were another buck or so. (I buy parts in bulk  ;))

The original light came from Lightmalls and cost me $36 I did a review on the light way back when and posted in on BLF.  I have modded it a bunch of different ways. I bought it to put XP-G2's in it. The Beam was terrible with them though, no way to get rid of the rings. Then I put the XML-U3's in it but not on noctigons and used a DRY driver in it. Now I de-domed them and put them on noctigons and the beam is beautiful. Perfect, nice tight hot spot and perfect flood and not a ring in sight!!

I should add this.

 I did have to remove the centering rings when I set the reflector in. With the centering rings on it was ringy and didn't throw well. So lowering the reflector all the way down was the key on this light. I covered the wires with the round paper stick on rings.

Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 02, 2015, 03:16:03 AM
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 02, 2015, 03:29:43 AM
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 02, 2015, 03:39:51 AM
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 02, 2015, 03:42:14 AM
Title: Re: 6xXML-U3 2x26650 mod
Post by: Spasmod on November 03, 2015, 04:30:38 AM
Thanks for sharing the modification with us Brad! that does indeed look awesome. Well worth spending the time to do IMO!

How far away roughly are those trees in the last pic?
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 08, 2015, 06:06:43 AM
About a hundred yards is all they are away in that pic.

But This light will light up the side of a forest at over a quarter mile and light it up bright enough to see what is in the trees!

I'm always marveled at the difference between a multi-emitter thrower and a single emitter one, especially the XP-G2 throwers.

The multi-emitter throwers just seem way way way brighter to the eye. I know for instance that if the meter says it's  250kcd that it's 250kcd. So your eye should tell you it's the same. But in reality it's NOT the same. When you throw 8 thousand lumens down range and hit a group of trees it's way more impressive than throwing 800 lumens at the same group of trees. Your eye just opens up and you see those trees, but when it's a single emitter you see a tree or part of it and it just doesn't seem like you really see what is there. IDK it's really hard to explain unless you see it yourself. 
Title: Re: 6xXML-U3 2x26650 mod
Post by: JohnnyMac on November 12, 2015, 07:26:56 AM
Brad, that is really awesome but I'm a bit confused on the driver thing.  That FET driver is designed for 4.2v, not the 8.4v 2 cells will provide.  If you purchased the Zener version then it will work for sure but you didn't happen to mention that in your write up.  If folks try to use a regular DD FET driver it will burn out. ;)

I really like how you added the side switch.  Maybe some sweet pics of the internal layout?  :D
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 17, 2015, 11:41:31 AM
Thanks Johnny, I'll go and add that. I completely spaced it off.  I put the zenor diod on all of the drivers I make, even the lights that are 4.2volts. You can kill the BLF without the zenor if you drive enough emitters with 4.2v. I killed a couple of them on SRK's. They would work ok with sanyo 2600's But high amp batteries would fry the MCU. Since then I just use the zenor on all of my lights so I didn't even think to mention it. Thanks for reminding me.

It's a fun light. I had it out to hunting camp over the weekend. I took a couple dozen out and handed them around for everyone to check out. 
Title: Re: 6xXML-U3 2x26650 mod
Post by: JohnnyMac on November 17, 2015, 01:48:13 PM
So you use the Zener diode on ALL your FET drivers?  Interesting!  That's actually good to know in case I build a huge multi-emitter.  I've had no issues with using it on a high amp triple XP-L and all the amps I can throw at it but I've not used one with more than 3 emitters yet.

So using the Zener with, say, a single XP-L HI, it doesn't effect anything with the output at all?  I never thought about it before but I guess if all you are feeding it is 4.2v then all that can go out is the same.  Very interesting.  Thanks for sharing!  :)
Title: Re: 6xXML-U3 2x26650 mod
Post by: 18sixfifty on November 18, 2015, 01:13:29 PM
From what I understand the Atiny13a can take about 5 amps, give or take a little, running through it before it starts to heat up. Smack the zenor diod in to bi-pass it and if nothing else you have one less part getting hot. Plus I'm lazy and since I have that driver build stuck in my head it's just easier to build them all that way. I also built a ton of the older two sided drivers. I'm not sure what I'll get up to next. I have a bunch of XHP50s to play with and some other fun stuff. Winter is coming soon so I'll have time to work on stuff while I'm snowed in.