Myo XP to CREE

Well I received my Cree's and optics today from cutter. First change on the Blaster went fine. Well after the wife went to work and the kids went to bed, I figured I would go swap my Lux in the XP to the Cree P4. The swap went great and prelimary checks went well. The Cree was noticably brighter but with a relatively ugly beam (without diffuser). So I went in the basement and dremeled down the Cree optic considerably and was able to replace the Myo XP optics with this. In order to fit the optics the plastic spacer in the XP was ground down. I tested this against my wall and was really impressed with the beam both with and without the diffuser. It was noticably brighter and much more pleasant to look at. Now comes the bad part. When after making some adjustments to the way the LED sat, I must of nicked the positive wire where I could not see. So when it was all done, I wanted to verify the LED was centered and turned on the headlamp. Well there was no light, then after about a full second the all to familar and smelly puff of smoke!!! The positive wire I nicked shorted out and blew a surface mount transisitor. But somehow the Cree survived!!! YIPPEE, so I sacrificed my 70 dollar headlamp, but was able to keep the LED alive. Oh well, live and learn.

On another plus side, the MYO lux ended up being removed from the star and installed in my original FF, replacing a greenie.

No I am off to order a new XP since I ned a headlamp for my hike next month. As with falling off a bike and getting back on, I think I wil go for the mod again with the new on. I just hink it will be after my hike. Enjoy.

So sorry to read about your mishap. You're sure it's a transisor? Can you try to replace it with another?

I once had an SMD output diode blow on me and I removed one from another circuit and replaced the blown one without any consequences. (other than ugly soldering.)

The cree will have survived ok because with the positive lead shorted the cree would be seeing no current.
Norm

eebowler, Thanks for the sympathy and the burnt part could be a diode, but it had three legs. I have been out of the SMT loop since my job is no longer working with PCBs. I purchased a new MYO today and hope to get the part number off that.

Norm, thanks, it been a while since working with board level electronics but thats what I figured.

So today I purchased my new MYO and immediatley went to work on swapping out the LED. I get everything mounted and working and find out that my ground down reflector isn't ground down enough. If the Cree reflector would accept the silver ring around the LED, it would probably work. I did not find this out last night because it shorted out during my short testing before I tried re-installing the heatsink. It is only off by a bit, it just won't allow to heatsink to catch its standoffs that hold it in place. With this, happening, the case won't shut tight so I aborted mission and re-installed the stock LUX. I will now search for a reflector/optics that will allow the LED to site more inside, or be short enough to sit in place of the stock optics. And as luck would have it I forgot to get the par number off the transistor to try to identify it.
Oh, and the burnt part actually burnt down a layer in the PCB and you could visibly see a trace a layer down. I hope to use some wire and repair damaged traces and try to salvage it. But the new MYO will be mod-less until after my hike, then its fair game.

Double posted, aghhhhh.

spinkid,
have you thought about modding it with a reflector and the cree?I thought about that myself,but still not completly sure if it would work.Skipping the opticsholder and using a 20mm lens and a Mcr17xr-or 19.Eventually filing the reflector down from the front side if it is to deep,till it has the height equvivalent to the one of the stockoptic+holder.What do you think about it?

Alex

boef800, I did think about the optics, but I never thought about filing down the reflector from the front (As I smack myself in the forehead....duh). The reflector should work better in this situation as long as the Cree could sit firm against it. This is because the heatsink is pressed in and locks on the standoffs. Now you have me more motivated in finding a reflector and trying again. But I think with my luck, I am going to wait until after my hike at the end of the month before I Attempt it again. I will however try and order some different types of reflectors. If you happen to try this, please keep me/us updated. Thanks

Hello, I e-mailed Petzl regarding my oops and they took care of me. I actually asked if I could buy just the PCB to see what they said. I was told they don't sell parts (figured this), but was told they received a light in with a shorted wire in the battery pack and asked if it would help me. I said yes, and received yesterday an entire head assembly. All I have to do is remove the cut wire for the batterypack and install my original battery pack and I am good to go. Petzl customer service is great!!!! Now, not to leave well enough alone, I am going to order some Seul LEDs since they are basically the same form factor as a lux and try to replace just the led and re-use the optics. I will also get some reflectors from the shoppe, to conquer the cree mod.

Wow - that's awesome! An entire head assembly!?! Lucky you!

Wow,that is cool.
Are the Seouls available on stars too?That would be a super nice and easy swap mod.I could imagine even with stock optic.
Keep us updated yes?
greetz,alex

boef800, I am not sure if the Seouls are available in stars. For me using the current star and just swapping LEDs is easy enough, so I am gonna go that route. Gonna be a week or 2 before I get to it, but definetely gonna try and will post my results.

SSC P4 on star...
http://www.led-tech.de/de/High-Power-LEDs/-3.5W-Seoul-Star-LEDs/Seoul-3.5W-Star-LED-(P4-Version,-Sel.-U)-LT-980_55_78.html

you can even buy only star,...
http://www.led-tech.de/de/Luxeon-High-Power-LEDs/Luxeon-K2/Star-Platine-fuer-Luxeon-K2-und-Emitter-LT-951_49_44.html

Given the choice I'd go for the one ready mounted on the star, since that is a SSC factory mounted one, and so should have a good thermal interface. That K2 star looks suspiciously like those Cree stars which have a layer of insulating material below the slug - insulating to both electricity and heat that is!