XR-E / SSC P4 Surefire U2 upgrade suggestion

[Amonra]

Dear Don,

It looks like many ppl on CPF own U2's and would like to upgrade them with the new XR-E or SSC P4 led's.
It seems that the major problem with doing this is that the electronics in the U2 deliver 6-7 Volts which are required to run the stock Lux5 whilst the XR-E/SSC require only about 3-3.5V.

So my suggestion would be to put 2pcs. XR-E / SSC led's in series inside the U2 to be able to match the voltages thus also doubling ( or more ) the U2's output with the same runtime, making it a much better mod ( in my opinion ) than just replacing one led with another.

I do not own a U2 so i do not know what space is available inside the head but i suspect that if you use one of the two methods ( or rather a mixture of both ) you have already tested in other lights, it could be possible.
The two methods i am suggesting are visible in your thread here: http://www.candlepowerforums.com/vb/showthread.php?t=138418
posts no. 2, 4 & 6

A pedistal with 2 back to back XR-E or SSC P4 led's ( whichever works best with the stock reflector ) just like the one in post no. 6 would have to be made to fit the stock U2 head & reflector.
Also a custom reflector like in posts no. 2 & 4 but with two halfs could be made to fit the U2 and added to improve the beam pattern.

As i said i don't own a U2 and I am not capable of building these myself so i tot of sharing my idea with you so that you might make it a reality for others to enjoy ( if at all possible ), also because my idea was inspired from your creations in the first place.

Thanks

 

[CM]

The biggest issue I see with the method (though I think the idea shows a lot of creativity) is that heat transfer is severely compromised. To maximize heat transfer requires maximizing contact area of heat beariing and heat absorbing elements. Putting LED's back to back will severely restrict heat flow. All the heat is choked off in the very small area at the bottom of the module. I don't really see a clean solution to multiple LED configurations that do not in one way or another severely compromise one or more aspects of LED operation.

 

[McGizmo]

Amonra,

It has been my experience that SF now uses some thread locking compound that can be a virtual weld. I have not attempted to take apart any of the SF lights in quite a while now so this may not be the case still. A 2 LED side shooter arraingement where the sink plane completely bisected the two reflector segments and was thermally bonded to them as well as the head would likely take care of the thermal issue. I believe we will be seeing even smaller SMD packages of high output which could even be better candidates for side shooting designs as time marches on. Both Lumileds and Nichia have put significant effort into small packages from what I have gathered.

However, to put the time and energy into a design and solution which would require a host of the nature and cost of the U2 is not a very economical solution, IMHO. I would think time better spent would start at the ground level. There are new LED drivers in the works too and multi channel drivers, at that.

I do agree with the concept here but question the feasability or desireability with so much new technology just around the corner!

 

[kenster]

Amonra,

It has been my experience that SF now uses some thread locking compound that can be a virtual weld.

I AGREE!

Ken

 

[CM]

I AGREE!

Ken

Red Loctite is what they use on the U2. Careful use of a torch will break it loose.

 

[kenster]

Red Loctite is what they use on the U2. Careful use of a torch will break it loose.

I could be wrong but I think these manufactures play around with different glues sometimes. I`ve opened a lot of lights and some can be a pain. I recently had a Q3 that seemed to be welded. Heated it, froze it and finally went at it with two pairs of 16" Channel locks destroying it but never got it open and I threw it away.

Ken

 

[McGizmo]

What Ken said. I have encountered some type of thread lock or adhesive that did not yield under elevated temperature or even deformation of the Al that was bonded with it. I mentioned it to PK and his response was a laugh. He never did get back to me on any posible solvent or means of disassembly and why, really, should he. :shrug:

 

[kenster]

What Ken said.

Don, don`t ever agree with me! :nana:


Ken

 

[Amonra]

As i said i am not familiar with the U2 or any other surefire lights for that matter.
but since i have seen many threads asking about modding the U2 with a Cree, etc.. i tot that some people do open them and try to mod them so i tot my idea would be of some inspiration.

I guess i was wrong, anyways thanks for the input.

 

[kenster]

Amonra, you were not wrong. I intend to open almost every light I can get my hands on. That is what makes this hobby fun to me. People open the U2 and mod it of course. Love to hear more ideas and keep them comming. I just wanted people to be aware I think the Manufactures of lights have been throwing some curve balls with the glues they use and sometimes an expensive light mod like using the U2 can turn into an unexpected expensive nightmare.


Ken

 

[Manzerick]

I used a butane torch to get the tailcap apart in my U2 and it still took some elbow greese

Red Loctite is what they use on the U2. Careful use of a torch will break it loose.

 

[gdict]

Butane torch on the tailcap??? That shouldn't have been necessary. The tailcap has a rubber seal that keeps it tight. I had a bad clicky switch and once I received my replacement cap from SF, I took apart the tail cap using some nice slip joint pliers with a thin piece of rubber to protect the finish. I cleaned the switch bringing it back to life and it is now in trusty service on an old 9P.

So, has anyone come up with a worthwhile upgrade for the U2? Mine has a donut and I know it could be brighter with a newer generation LED, but I don't know enough to know which would work. I don't need anything extreme, but it would be nice if it had a little better performance. I love the 'package' but yearn for something more.

Cheers!

Greg