A tight retaining ring can kill an LSH!

I recently modded my LSH-S bezel with a TW0H Luxeon III emitter, a mineral glass window, and an SO17XA reflector. It was a real beauty for about two weeks. It is dead now!

During the process of removing the heatsink/regulation board assembly, I decided to lightly tap the bezel on a formica tabletop desk to help it fall out of the bezel when I was having a hard time grabbing it with a pair of tweezers. It did fall out easily, but after that it stopped working. I did two diagnostic tests to determine if the emitter died. I touched the leads of my digital ohmmeter to the emitter's leads, and got a 137.8 ohm reading. I attached the leads to do the meter's diode test, and got a +.230 reading. I made all of the contact points on the board, the copper wave washer, the retaining ring, and the bezel's threads....... "squeaky clean", but to no avail. I believe that I can see one of the die's wires inside the enclosure, in front of the die instead of on the side of it. The positions of the wires look strange, not like ones I have seen in the past on other Luxeon emitters.

Any ideas what went wrong? Any ideas on what tests I can perform to find out if the emitter has died, or if there is any other damaged component?

I was just getting acquainted with my new bezel when this happened!!! BOO HOO!

Re: I tapped my LSH bezel on a table,.... and it died!

You could get a 123 cell and attach wires to the appropriate leads of the LED directly from the battery, and direct drive it for a few seconds to see if it works. Make you you put the wires in the right places though.

Good luck - sounds strange that it would die from tapping.

Re: I tapped my LSH bezel on a table,.... and it d

I've diagnosed a Lux that I thought was dead by doing what Endeavour suggested. Make sure you get the polarity right, though, otherwise you will *really* have a dead Lux /ubbthreads/images/graemlins/crazy.gif

Re: I tapped my LSH bezel on a table,.... and it d

I use a 3led dorcy to diagnose a dead lux, just remember the positive of
lux has the full minus sign, the cutout minus sign is the negative.

hope this helps.

Re: I tapped my LSH bezel on a table,.... and it d

luxlover- if you are really interested in other people's ideas on what might have gone wrong, I think you should have the courtesy of telling them the whole story. I think the title of this thread is very misleading, and may cause concern among others (about "tapping" their Arc LS bezel) where none is warranted. The more information that is presented, the more accurate the answer is likely to be.
No offense intended. /ubbthreads/images/graemlins/smile.gif

Peter

Re: I tapped my LSH bezel on a table,.... and it d

/ubbthreads/images/graemlins/popcorn.gif

Hey look guys, bluewater is waiting for my full confession. Help is on the way, "Friend from the North!"

Don't get a tummy ache eating too much of that CPF grade popcorn!

Peter,
Thank you for the gentle push! No offense taken, I assure you. You are correct that lightly tapping my LSH bezel on a hard table couldn't possibly have damaged it to the point that the emitter doesn't light up at all. But as we discussed last night, my action of overtightening the retaining ring was the final act that did do damage to either the emitter or some component on the regulation board. I sent the bezel back to you this morning for your assessment of the damage I caused. In this regard, "be gentle with me!"

Peter, I wish to offer an explanation as to why I did not write a post after we spoke last night......
1. When we finished the call, I checked the thread and found no posts beside my own. I figured that there was no interest in my issue.
2. At that point I shut down the PC and proceeded to "count sheep!"
3. This morning I checked the thread and saw no posts before I left my home to attend the St Patrick's Day Parade in Manhattan.
4. I left my home before Endeavour's 11:44AM post, which was followed by a post by greenLED, cqpeanut, and yourself.

I would never knowingly deceive my fellow CPF comrades. Circumstances prevented me from divulging the truth about my bezel's malfunction, until I read the posts about 8:00PM EST.

I hope that I didn't cause anybody heartache, as a result of my initial post. I will be much more attentive in the future, and will focus on how new information should be used to quickly update old information within a thread.

Peter happens to be a good samaratan, and he has benefited all of us with his observation. Don't let me hear that any of you have been overtightening your LSH retaining rings. I will sic Peter on you if I do! He bites!

<font color="blue">Edited thread title to reflect the truth:
Was: I tapped my LSH bezel on a table...and it died!
Is: A tight retaining ring can kill an LSH!</font>

luxlover, you have a PM.

Got it! Reply on the way....

luxlover- Please accept my apology, I have made a mistake. /ubbthreads/images/graemlins/blush.gif

I thought that you had made your post *after* our conversation, not before. I have not been able to spend much time here lately, and I didn't notice the time of your original post. I was under the (false) impression that you were posing your question(s) after I had informed you that that overtightening the retainer was likely to have caused your problem.

Once again, my apologies...

Peter

I don't thing you did anything wrong, Peter. Reporting an error in information placed in a post that has the potential of misinforming hundreds of CPF members, "is not a wrongdoing." Both of us were locked in a "space/time continuum", and fortunately we broke free of it together. No apology needed, since I had to update the information per our phone conversation anyway. There is still peace in the kingdom!

Now to what I believe happened when I tightened the retaining ring, but this time in detail.....
At some point, as I slowly turned in the retaining ring with my anti-magnetic tweezers, the pressure of the "emitter/regulation board/ heatsink" assembly started to increase against the reflector and something had to give. I think that the assembly started to spin along with the ring, causing the end of the reflector to "dig" into the encapsulation material of the emitter's casing, twisting the die wires away from their points of contact. This theory could very well explain why the wires were up in the air and completely out of place within the clear high domed enclosure. In all of my other single die Luxeon emitters, the two die wires are in line with each other, are symmetrical about the die, and are positioned at the same level as the die. The die wires in my emitter are in limbo. Also, there are different kinds of floating particulate matter inside the dome, visible to me, that was not there when the emitter was working.

Is my theory plausable, Peter? If so, then the bezel needs a new emitter "and carfare back to Brooklyn." I look forward to your assessment of the damage, when you receive my bezel on Monday.

PS: I thank you for advising me to change the subject of my original post, to reflect the truth. I feel better, knowing that I made the change and worded the subject as a "possibility" and not the definitive cause of the failure, pending your examination of the bezel.

Your theory is plausible. I hope it's only the emitter that needs relacement. Unfortunately, you may also need a new LT1618 chip if the light was switched on with no load. /ubbthreads/images/graemlins/icon15.gif

Peter

Neither of us needs the hassle of replacing a multi-pinned chip, especially with such small scale legs. It scares me to think of it. In the event that the emitter is the only defective item, please save me the emitter with the same binning code as the one you used the last time. With my 2xAA battery configuration, the purpose for my desire to have you do the mod, my bezel needs all of the Vf help it can get. It was a "lean, mean, lumen machine" before I tampered with it. Let's resurrect that puppy, shall we?

Hey you amended your profile! Good man!

If you need a coil pm me with your addy and I'll sned you one.

Anyone know exactly how tight the retaining ring should be? I usually tighten until its just snug but I probably err on the conservative side. The ls that I use every day at work gets dropped occasionally and the optic usually gets knocked out of alignment.

Where are you Peter!!! As you can see, bhds and I are dying to know "exactly how tight the retaining ring should be." I heard that one tightens it until the copper wave washer feels like it is resisting the ring, and then one stops and applies thread lock paint, or for the simple minded like myself, clear nail polish or nail hardener.

Regarding any advice that Peter may offer me in the care of my new and improved bezel, when he says JUMP, I will reply HOW HIGH?

It can vary a bit because there are at least two different wavy washers, but I typically tighten the ring till the washer goes flat, or nearly so.

bhds- Swapping the optic for an IMS reflector will help with your problem of the LED going off center. The reflector "grabs" the dome in a way that prevents it from moving much. It will remain centered when dropped, unless it is dropped really hard.

Peter

[ QUOTE ]
LitFuse said:
bhds- Swapping the optic for an IMS reflector will help with your problem of the LED going off center. The reflector "grabs" the dome in a way that prevents it from moving much. It will remain centered when dropped, unless it is dropped really hard.

Peter

[/ QUOTE ]

/ubbthreads/images/graemlins/icon23.gif Have been thinking about trying the IMS reflector but for use at work the fraen is the cats meow. /ubbthreads/images/graemlins/cool.gif I do have a couple ls's that I kept nx05 optics in. Keep one in each vehicle and and they work very nicely for general outside use.

Peter,
It makes sense to stop turning the retaining ring, only after the copper wave washer is flat against the bottom of the heatsink. To stop before this occurs would probably provide less than perfect conductivity between the negative side of the circuit (body), and the negative lead to the emitter (copper track on bottom of heatsink). This is where a "gentle touch" comes into play.

Would you describe what part of the emitter is being pressed upon by the reflector as a result of the pressure applied to it by the retaining ring against the heatsink/board assembly? I have heard stories about emitters becoming torn away from the heatsink as a result of a user detaching the sections of a bezel. Apparently, the reflector "digs" into some part of the emitter, and twists it from the heatsink or damages the emitter tabs. I think that before the bezel is disassembled, the pressure between the emitter and the reflector should be lessened, so that all parts remain intact upon removal.