First Mod, need some advice from the pro's

[h22]

My Jetbeam RRT-2 suffered an emmitter failure (lense poped off), So I am looking for a possible upgrade to replace it. There are two options I am considering:

1, replace the LED with the same one it came with ( Cree CR2 i think????) or possibly a "whiter" tint. I prefer the whiter tints compaired to the yellowish tint it came with.

2, Upgrade to a better emmitter, This is where I was looking for some ideas from other modders.
What is out there that is comprable, if any? Should I look into a possible SST-50 :naughty: upgrade? ( this, of course, brings up driver mods and heat issues.... )

If I recall corectly, This light was rated @ ~240lm, I was very happy with it, but more would be nice :devil: .

Possibly just overdrive the "stock" replacement a bit? again if i recall correctly the current draw from the tail cap was ~1000ma. dont know if the latest releases could handle a bit more?

Also, where is a good place to buy these emmitters?

Thanks, Joe

 

[The Dane]

Regarding LED's for a given reflector size, less is more.
Meaning the smaller the emitter area the better focus gets, so going from 1x1mm to 2.25x2.25mm will make your light go from spot to flood.

Regarding power and cooling, from 3W to 18W is a big jump and useability goes down the drain.

 

[h22]

Regarding power and cooling, from 3W to 18W is a big jump and useability goes down the drain.

Good points, I really wasn't considering a full on 18w mod, hence the . even if I could modify the drive circuit to handle the amps, and get an 18650 that would do it, heat would be untennable.

But I have seen other lights, both custom and OEM that are a 1x18650>SST-50 combo., most advertise ~400-500lm.

Possibly a smarter way to go would be a similar emmiter driven to ~1500ma?

again, looking for advice.
Joe

 

[rayman]

You could go with a XP-G R5 driven at 1.5A. Changing out the emitter is pretty easy but changing out the driver will be a problem. One big problem is the selector ring. If you want to start modding why not just take a Maglite .

rayman

 

[h22]

[ You could go with a XP-G R5 driven at 1.5A. Changing out the emitter is pretty easy but changing out the driver will be a problem. One big problem is the selector ring. If you want to start modding why not just take a Maglite .
/QUOTE]

OHHH believ me a magmod is on my "to do" list!
But Me being Me..... when I start a mag mod i will have to go overboard... like an SST-90 monster. I have seen a few done, short on spare time and workspace, so that project will have to wait till I get a bit more of both.

So the XP-G R5 is a good candidate?
I remember looking at a spec sheet on that one ( i think:thinking: ) a few months ago.....
Where is a good source for them? digekey? mouser?

as far as modifying the driver baord, I will have to look at the JetBeam board to see if it is even possible. If It is PWM then it could be tricky, but if its CC then possibly adding a resistor to the transistor gate drive would do it, providing the transistor can handle the load......

I am an avid DIYer, and I know a little bit about electronics :thinking:, So just replacing the emmitter goes against my most primal urges....

 

[Fichtenelch]

I'd just go for a XP-G R5 and you're done.
Everything above an xp-g combined in a small package is a waste of money.

 

[h22]

I'd just go for a XP-G R5 and you're done.
Everything above an xp-g combined in a small package is a waste of money.

Yea, thanks. Just looked at the specs and the XP-G R5 is a perfect replacement. same current draw more light. Problem is I found them at Cutter Electronics, but they dont seem to ship to America.

Is there a suplier here in the states that I could use?


Also, I took the light apart last night (a bit of a pain!) and the LED is mounted in a ~10cm semi-round thin aluminum PCB that is glued to a heat sink with a white silicone like compound.

Also I looked at the PCB that controlls the LED, There is a ATmini Atmel controller in a SOIC 8, this I assume is the main control processor.
there is also a small multi-pin chip mounted near the power transistor (probly a MosFET in a SOT-23 6pin) that is smaller than a SOIC8, but is finer pitched with 10 or 12 pins. Possibly this is a boost/buck type of device? It apears that the PN has been sanded of of this one:sigh:.

But the thing I did note was what apears to be a current sense resistor in line between the FET and the LED, so my thought is that anyone wanting to tweek the output could try modifying its value ( its an 0805 footprint ).

Well, im off to try and find a suplier for both the CREE and some heatsink mounting compond....... ( mouser was a no-go )
Thanks!

I will try to get some pics up later of the dissasembly!

 

[tx101]

Cutter ship worldwide (well the last time I looked )


EDIT ... just had a look ..... yes they still ship to the US

 

[Justin Case]

I have some extra Cutter XP-G R5s. I can sell one to you to help avoid the shipping delay and expense in ordering from Cutter. The only caveat is that I ordered my batch before Cutter started to offer R5s in specific tint bins. PM me if interested.

 

[h22]

Cutter ship worldwide (well the last time I looked )


EDIT ... just had a look ..... yes they still ship to the US

Thats strange.... I just tried to place an order and the pull down menues for billing and shipping would lock out when I treid to select a state in the US...... Wierd. I will try it again.


Looks like Digikey has some offerings, but I need to see if they offer the 10mm round PCB.

 

[h22]

I have some extra Cutter XP-G R5s. I can sell one to you to help avoid the shipping delay and expense in ordering from Cutter. The only caveat is that I ordered my batch before Cutter started to offer R5s in specific tint bins. PM me if interested.

might be interested in a couple, but what does that mean exactly " no specific tint bins" ? does that mean they are still ~130 lm per watt just a crap shoot as to what tint it might be? I would prefer a more white tint.

Do you have a paypal account?

 

[Justin Case]

Send a PM for PP info.

Tint <> flux. The flux bin is as I specified -- R5, which is a min of 139 lumens at 350mA drive. R4 is 130 lumens minimum. These XP-Gs are on 2mm thick, 10mm diam MCPCBs.

The order code for the XP-Gs I have is XPGWHT-L1-0000-00H51 R5. It appears you can now specify specific tints in 1A, 1B, or 1C for XP-G R5s. Kit 00H51 encompasses the following tint bins (it is my understanding that when I made my order, what tint you actually received from of this tint range was a lottery):

0A, 0B, 0C, 0D, 0R, 0S, 0T, 0U, 1A, 1B, 1C, 1D, 1R, 1S, 1T, 1U, 2A, 2B, 2C, 2D, 2R, 2S, 2T, 2U, 3A, 3B, 3R, 3​

 

[h22]

Send a PM for PP info.

PM sent! thanks.

 

[h22]

Justin, I got your shipment, Thanks.

Well as this is a fairly hum drum mod i havent been taking any pics, but I think I will when this starts going together.

I have the XP-g mounted, It will require some attention to the reflector though as it will short out the soldier pads when lowered down. I will either cut a peice of plastic to guard it, or (preferably) open up the end of the reflector a bit and cover everything with some glow/poxy:twothumbs.

As far as driving it to 1.5 amps..... is that safe? I tried to play with it wit a regulated benchtop power suply and it would not go over 1.1amps, but that could have just been a safety regualtion on the PS.

 

[h22]

Ok, so I put it all back together to see how well it worked.

:thumbsup:. I managed to get the emmitter fairly well centered, and it produces a very white beam compaired to the origional R2, it had a bit of a yellow greenish tint to it.

I cant tell if it is any brighter at this point, but i think it is. I dont have the origional to compair to so its hard to say.

Two things to note.

1, the bigger emitter ( even though the LED is quite a bit smaller overall ) does not throw as focased a beam, but it is still a nice beam :twothumbs.

2, the reflector has to be extended out quite a bit to get a good focus, this is good and bad. The good is it keeps the reflector up off the LED so no worries about shorting out the leads. The bad is that it is out so far it almost exposes the o-ring, not a huge deal as that could be done with the stock LED, but it wasn't a prefered focus with the R2. The problem is that now the reflector portion has a bit of wiggle to it, not a huge deal but it does tend to make it feel a bit flimsy.

I measured the amp draw at the tail cap, initial start up was 1200ma, but it quickly settled to ~1000ma. I need to order a few 0805 sized current sense resistors to play with, the XP-G is rated to 1500ma and 460 (if i remember correctly ) lumens. IF I can get the driver to do it that would be quite the little pocket rocket.
If I am able to get 1500ma to the emitter, i think heat will be an issue, it does heat up now but no more than with the R2. However, with a modified current sense resistor, the "mid" mode should be ~750ma, so that woul be good for a lot of light (close to R2 @ 1000ma i think), and the full power for the WOW factor.

As far as the loose reflector, I plan on doping up the threads with semi-hardening thermal silicone, that should tighten it up and help with the heat dissapation.

I also got my glow powder in the mail, so i will be figuring out how to put that to good use as well.

I am now hoping that jetbeam will offer the XP-G in the RRT-1 ( large reflector ), that could be a dynamite thrower!