Problem with LS second

I received a few weeks ago, two of the $50.00 special seconds and have been carrying one of them (First Run #1577) since, probably turning it on for 10-60 seconds at a time, a few times each day, basically playing with it. Just a couple of days ago, I noticed that as I screwed the tailcap in, the light would turn on as it should, but then as it was screwed almost all the way in, it would turn off.

Today, it turned on, only it was very dim. As I screwed the tailcap in all the way (which a few days prior would turn the unit off), it still was dim, but did not turn off. I am assuming it is running in the moon mode (although I really don't know as I haven't run a battery down in either of the two units I received, just got them).

When I switch batteries between the two units, the problem remains in the problem unit. I am using Sanyo batteries. I took a Surefire battery out of my E1e and put in in the problem LS, and it wouldn't turn on at all. I tried putting some aluminum foil behind the Sanyo battery in the LS and there was no change.

I had read about NASCAR's problems. Is this related? It certainly is unrelated in the fact that I didn't return mine in the seven day period for the refund on the seconds. This wouldn't be such a big issue, but unfortunately, my wife has been observing all of this. Any suggestions from the forum or Peter? I really want this light to work, as I think it's a great design, It's the perfect EDC for me!

I'll appreciate any advice that can be offered. BTW, I got to CPF from Bladeforums, and have learned more about lights in the last month than I could have imagined. I've ordered and received an E1e, E2e, 2 Arc LS's, 2 Arc AAA 3.1's, Arc AAA LE, and an Opalec Newbeam. Thanks for the advice!

i too have 3 arc-sls's

one of them has the flex problem i believe you speak of.
i cant remember if anyone fixed that problem?

anyone?

mike

My sLS is just bearly starting to exibit the same problem. It is much worse after I change battery formats. Corrects itself somewhat, but not totally, if I clean off the positive contact a bit.

I have tried cleaning the positive contact in the head, makes no difference. On a positive note, I almost sold this SLS to a buddy of mine who really liked it upon initially seeing it - glad I didn't do that!

I have a second that was supposedly a repaired flex problem that still has the same problem. Very intermittent but I guess I'm going to send it back as I don't feel confident should a situation arise when I depend on the light.

I thought that problem was fixed?

All of these (even the ones past 7 days) will be replaced by Arc.

The flex still occurs. I have evidence it is even in the new rev2 (although to a lesser degree). We have tried several fixes with varied results. We have a new fix we are going to be trying soon. We call it the "annular ring" fix. I hope to have this proven by the time the LS2s are ready to ship.

The reason the flex is so annoying is its intermittant nature. A unit will test fine and then at a random time it starts to act up. We manage to catch some when they are manufactured. We catch a few more later on when do a QC sweep of inventory. But then others fail while in the hands of our customers.

Peter Gransee

I bought three arc ls hybrid seconds. One of my three I had to disassemble the bezel from to fix the collimator's dirtiness and a large gap between the collimator and bezel (someone didn't screw it all the way down before locktiting the bezel). This dissassembly has had a side benefit for me. After I reassembled the arc it began to show flex problems. However every now and then when the light goes into moon mode by itself all it takes is a little unscrewing and retightenning of the bezel and bingo the light is back to full brightness. Everytime so far this solves my problem instantly.

Except one other time my light became dim and the bezel wasn't the culprit. When I openned the battery holder, the gold cobalt nipple in the head had black burn marks from lint or something; I scraped it off and added a little special lubricant called corrosion block for marine hardware (it comes in a foam dispensing spray type aluminum can and is white foam which turns into a blue liquid, it prevents rust and lubricates). This solved this problem.

So I know what to do if any of my other arcs act up. The hardest part is heating the bezel with a lighter and unscrewing it from the locktite without damaging the unit.

I'm going to try and waterproof my arc ls hybrids as well. That is I'm going to waterproof them from downpour. I'm going to go looking for either a transparent squishy thin sheet I can cut into a circle and slip in front of the collimator and screw the bezel into the thin sheet creating a seal. Or I'm going to get a thin rubber type sheet and make a ring to go under the bezel and leave the collimator front exposed. I'm going to look for some compound to insert in the bezel threading to block moisture while not locking the bezel threads. In addition I may get a thick rubber band and coat its underside with something to create a seal and slip it over the bezel screw openning creating an additional moisture barrier here. I may also apply epoxy to the inside of the head on both sides carefully so as to not get any on the luxeon emitter or the cobalt nipple but at the same time creating an impenetrable moisture barrier for any water that gets in say if I crack the unit open in the rain to look in the battery compartment for whatever reason, theoretically.

Well I just cracked open my bezel on my arc ls hybrid again to have another look inside and I found something that I must share with you because my former post about epoxying will result in disaster if not done properly.

The luxeon emitter is sitting on a circuit that is printed on a flimsy round backing that is flexible and under flexing tension like a rubber band because of how its attached at one end. It is not glued down to the aluminum backing and is not stable. One dab of conductive silver glue? has been placed over a gold outer strip on this flimsy board. This conductive silver glob extends out from the board to the peripheral aluminum backing and touches the threading on the head into which the bezel is screwed. This silver glob is badly crushed under where the bezel is screwed down. I believe that the silver glob is making contact with the end of the bezel housing the collimator and the electricity is flowing through the threading to the outer aluminum head and to the battery housing. This silver glob is what is causing FLEX FAILURE which souds like this circuit board flexing. Obviously the silver glob is from time to time not making contact with the bezel's end maybe because it gets burnt material in it like what happens on the gold button in the arc head touching the positive battery nipple and it has to be wiped or unscrewed and rescrewed. So if you placed epoxy all over it there would be no more electric current and your flashlight would be killed.

However, I might get some epoxy and glue the back of the board flat because its flexing just anoys me. Then I may get some more of that silver epoxy and run that silver stuff along the entire length of the gold circuit strip out to the housing wall and permanently eliminate flex failure. MAKE SURE NOT TO CREATE A SHORT BY GETTING IT ON OTHER PARTS OF THE CIRCUIT BOARD. I also may consider cutting a thin piece of metal but stronger than aluminum foil and run it out to touch different parts of the arc head and see the effect. If I can eliminate the need to touch the bezel tnen it will be even better.

Only after all of this I may epoxy the whole thing in place being careful not to epoxy over any crucial part that is needed to complete the electric circuit, like the silver glob.

The other side of the arc head where the gold nipple is should be no problem for epoxy on the other hand.

Thank you Peter, most generous! I'll be sending it back today, and buying more ARC products in the future. Particularly AAA's as stocking stuffers.