Waterproofing the arc ls hybrid and getting rid of flex.

I just bought 1 $20 conductive silver epoxy kit, 1 JB Weld nonconductive epoxy cold nonconductive weld $4, 1 epoxy quick setting kit $4, 1 supergulue gel $1, 1 GE silicon II kithen and bath sealant.

I'm going to use the superglue to glue the circuit board around the arc ls luxeon emitter flat against its backing so it'll be easier to work with it. Then I'm going to apply the conductive silver epoxy LIBERALLY along the entire gold contact strip out to the wall of the arc's head. When all dry I'll epoxy over both sides of the arc's board probably using JB's Weld since it has a temperature rating of 600 F.

Finally, to waterproof the ARC LS hybrid I am going to use GE silicone II kitchen and bath sealant which comes in a tube so you don't need a caulk gun. It is clear and I bought it from home depot. It bonds somewhat so I need to be carefull so I don't locktite anything. I'm going to apply just enough thickness of this stuff under the bezel after I remove the collimator. I'm also going to apply a ring of this silicon to the arc's head just below the threads that mate with the bezel to give the bezel something squishy and waterproof to screw down into.

This should make the arc waterproof in a rainstorm but not for diving. This should also permamently get rid of flex failure. Even if flex still comes back the bezel will still be left free to twist and remedy flex failure with this fix.

All the parts cost me $37. However, the bulk of this price was the conductive silver epoxy which cost $20. Considerring that I'll be fixing 3 Arc ls hybrid seconds which I got for $49, I still consider this a steal.

That sounds like a plan. Please report back to the DB on the actual process and any tests you may perform on your lights.

I finished working on my arc ls hybrid seconds. I lost one. DO NOT USE CRAZY GLUE on the arc circuit board to hold it down. I pushed down on my circuit board with toothpicks while letting the crazy glue bond the back of the board to the aluminum disc heatsink. Some crazy glue got on the circuit and the light doesn't work.

However the other two arc ls hybrids worked. One I completely weatherproofed. The other one I did a mediocre job because I could not get the bezel loose.

For the completely weatherproofed arc,this is what I did. Unscrewed the bezel, sometimes heat is needed from stove or whatever to undo the locktite; mine just openned with a twist. The collimator lens is held by a ring screwed behind it along with a plastic washer. Unscrew it; I used two jeweler's screwdrivers to stick in the two holes on the ring to turn it. Place the collimator, ring, washer and bezel aside. With 2 AA batteries in my holder, I twisted the flashlight on and kept on twisting and the circuit board pops out the arc's head. The rest of the head and the battery holder can be put aside. There is a gold strip along one half of the circle of the circuit board on its outside. In my arc silver conductive epoxy was dabbed on this gold strip and smeared out to the housing wall and along the edge of the heatsink disk and around to the other side of the circuit board where the batteries face and this silver epoxy ended on the outer gold strip on the circuit board on this side as well. Obviously, someone was trying to circumvent the housing and just run the current through the epoxy. Without the epoxy the current would have to travel through the head to get to the other gold strip. I took my silver epoxy kit and mixed up enough. I used toothpicks to cover the entire gold strip and worked it out over and to the other side coverring the other gold strip for the same length as the original gold strip. Be careful not to make the outer side of the heatsink to lumpy or it won't fit back in the head; smooth it with the toothpick, but you could always sand it when dry later. Then I mixed up some JB Weld nonconductive epoxy cold nonconductive weld and I used toothpicks to apply this carefully over the entire circuit board except for the portion coverred by silver epoxy and except for the luxeon bulb and I did not put this on the outer side of the heatsink washer because this epoxy is nonconductive and will ruin the heatsink; I left the outer edge bare aluminum except for the portion coverred in silver conductive epoxy. I also left the battery gold cobalt contact bare of course. But no circuit board is exposed at all any longer to moisture. My arc ls hybrid has now been POTTED.

Then I took lens crafters moist eyeglass cleaning towlettes in sealed tinfoil pouches and I polished the collimator spotless. Then I took my GE silicon II sealant and I applied it to the inside of the bezel that is the bezel's inner metal lip that buts against the collimator. YOU MUST APPLY A HUGE WAD of silicone not a little bit. It will get all over don't worry. It is the only way to get a good seal, trust me. Put in the collimator without getting fingerprints; one side of the collimator has a tab and one side of the threads in the bezel has a space running down the bezel for this tab cuttin a lane down the threads. THese must match up or your collimator won't fit and you drop it getting finger prints all over it. Put washer back in and screw ring tight. Silicone should be oozing out front. Get lots of lenscrafter premoistenned paper and scrub off the silicone and all marks leaving the front spotless EXCEPT FOR A NICE FLUSH BAND OF SILICONE between the bezel and the collimator. NOW IT's more waterproof than the rev2 possibly. Now when ciruit board dries in maybe 3 to 4 hours put it in the head. Then get the assembled bezel and look at its threads. Notice the lip of metal at its top that is on the collimator side of the threads. Apply LOTS of silicone to this entire lip surface LOTS. THen screw it down tight. Get toilettes again and scrub spotless except for a flush band of silicone in this bezel and head junction. Once again now this should be as water tight as the rev2's one piece body. Even If water manages to get in the circuitry is potted and only steam should collect on the collimator or the batteries should go dead or it could pit the aluminum battery housing threads because aluminum dissolves in saltwater with electric current. However, the circuit board and luxeon should be impervious as long as you potted the entire thing which takes a lot of patience to do carefully and thoroughly.

I turned it on and it works beautifully. It's even better than before because my collimator is spotless like a diamond.

My other arc ls's bezel would not come off. So I potted the battery holder side of the circuit board. I smeared silicone on the outside of the bezel and head junction working it into the crack. I also smeared it on the bezel collimator junction and cleaned off all of the collimator with the moist eyeglass toilletes except for a narrow band of sillicon I had to leave on the collimator for the water seal. THis arc is downpour prood.

The other arc ls might even be dive proof.

I screwed up with the first arc second. NEVER use crazy glue with circuitry. It screws it up unlike epoxy. You can pot the whole thing in epoxy and no problem. Get a little bit of crazy glue on it and its dead.

ledfanfromjuno,

that is positively the most detailed, most courageous enhancement effort I have read to date on the Arc LS. Great job! Inspiring even. I have 2 Arc SLSs in my posession, which to date, have been flawless in their operation, apart from crushing batteries. Guess I'm lucky. But if ever had to take mine apart, your post above is gonna be my reference and standard bearer.

Thanks for all that info!

ledfafromjuno, you are just about the bravest man i have ever encountered! i am sooo sorry to hear about you recent loss.

how is the thermal transfer? i am just a little concerned about the epoxy and stuff insulating the led and electronics and making the thing go pop.

My modified arc ls's body gets warm still quickly. I took it walking with my pet possum last night; my wife works in an animal hospital during the night shift. Because it gets as warm as it used to as quickly I assume it is transferring heat via the heatsink to the body normally.

When I worked on this flashlight, I made sure that only silver conductive epoxy touched the gold strips and was exposed over all the gold contact strips on both sides of the circuit board, that is the side facing the collimator and the side facing the battery compartment. THe circuit board is two circular disks held together by a narrow junction and these two discs are bent over a aluminum disc creating two surfaces one facing the batteries with the cobalt nipple and the other facing the optics. There is a complete circular gold strip on the outside periphery of the circle in the battery circui. There is a half circle gold strip in the optics circuit. Both must ONLY be completely coverred in silver epoxy. If you coverred them in regular epoxy you'll loose all the conductivity at the points coverred increasing flex likelihood. The JB cold weld epoxy I coverred the other parts of the circuit board with the copper coils transistors or whatever the components were. I even coverred the barely visible copper inside the luxeon emitter right next to the luxeon's clear bulb surface. I had to scrape spots off with a toothpick before they hardenned on my bulb. BUT now my luxeon and circuitry is waterproof. I could probably soak my entire flashlight guts in a fishtank outside of the flashlight with no problem. JB's cold weld nonconductive epoxy is great. It's thick so easy to apply and not runny. It takes a long time to set up for I didn't buy the quick type. It is supposed to be ok up to 600 deg F. There is a picture on the packaging of it being used to repair an engine block. It says its waterproof. I believe it is stronger than regular epoxy. It has a temperature rating several hundred deg better than regular epoxy.

I made sure when I potted the arc to cover the circuit board and around it so no water could get underneath. Some parts are covered with JB and the side with the gold circuits are actually potted in silver conductive epoxy for I didn't want to take any chance in the JB creating a flex problem. JB and silver merge together at each ones border creating a continuous seal(no space between the two epoxies). But I left as much of the aluminum disc which is larger than the circuit board as bare as possible with no epoxy coverring it. So I have a little part of the circle exposed as bare aluminum on the optics side. Lots of the edge of the aluminum circular wafer is bare aluminum for I did NOT rub JB weld around the outside of the aluminum disc on to the other side since this would insulate the aluminum and cause HEAT faillure. However on the one half circle gold strip on the optics side I did cover with silver epoxy and run the silver over the edge along the entire half gold strip to the half of the other gold strip by the cobalt nipple.

This is how I tried to maintain the functionality of the heat sink while still trying to solve flex and still potting the entire thing.

I'm really dissapointed my other arc wont open up even under the stoves flame. I really wanted to have two perfect arcs which would make up for my other loss.

I think my arc is even better than the rev 2. It is more waterproof because of its potting. I think the silicone band under the bezel collimator may be more water proof than the bezel pushing against pyrex or lexan.

I think arc should have just designed the circuit board with the gold strip going directly from one side to the other along the narrow band connecting the two floppy circular circuits together completely bypassing the aluminum head and housing.

wow that is great! peter...are you listening? wold this be possible in a ls2 rev2?

you have a pet possum...that is cool, what is it like?

I think that if peter offers this type of flashlight that he should ask more money for it because it's a lot of work. A le model. I don't think its possible to do a fast production assembly with something like this. But many fine manufactureres of stuff like japanese samurai blades http://www.bugei.com/customswords.html and custom knives with painstaking rustproofing applied http://www.chrisreeve.com/onepiece.html do take the time and charge a substantial premium for these models which are survival weatherproof or tough (samurai sword is tough not weatherproof it needs to be coated in robarguns np3 electroless nickel weatherproofing to be weatherproof except for the blade edge which must for sharpenning remain naked).

I would love to see arc offer a potted arc with true water sealing at all cracks in the housing like the front of the bezel pyrex lexan or collimator mating surfaces. THen arc could make sure at the same time that there absolutely is no heatsinking problem. Maybe make the two gold strips on both sides continuous through the narrow joining bands. Arc could sell these as a special custom le unit modified in shop separate from regular assembly.

Look at the new xbox videogame steel battalion. The company put a lot more effort into the videogame than other game makers, a lot more effort which shows in the screenshots. http://www.ebgames.com/ebx/categories/products/product.asp?pf_id=227919 But this company charges $200 for the game, and they're selling well according to ebgames.com because people are willing to shell out this much extra money for the good quality. That's a $150 premium over other videogames retailing for $50.

Yes, I have a pet opposum. She is very gentle and affectionate. I had her since she was half the size of my outstretched palm. I carried her everywhere with me as she was groing up inside my shirt like her mother's pouch. I fed her in restaurants, took her grocery shopping etc. without anyone knowing. Now she looks at me like her parent or something. Although I allowed frequent contact with all strangers as she was groing up she still gets nervous around them and darts back down my shirt. I have to walk her a lot though because I can't let her loose in the house. We have no backyard, just a balcony. We have hawks, owls and some kind of vulture or condor here at the beach in southern california that I think the dumb feds imported into the wildlife marsh right behind everyones houses along the beach. These idiots also imported a whole family 15 coyotes into this residential neighborhood right in urban orange county along the beach. So I can't even let my possum out on the balcony because the birds will eat her. I wasn't able to potty train her to my satisfaction and she chews doors in the house when she gets frustrated. She gets violent with innanimate objects when she gets frustrated just like bears do that I saw on a tv show about bear training. However, she never bites people just stuff. Even when the people at my wifes work do some painful stuff to her (veterinarian stuff) she just screams and tosses her head but she never has bitten anyone. She is a great pet.

i use ca a lot fixing cracked boards in monitors and such.
i bet it is insulating something from ground or b+
as far as damaging stuff ca is pretty inert.
before you toss it send it to me for an autopsy
ps i am going to open 2 ls seconds and swap bezels for a pefect match and to clean colimaters.

Originally posted by ledfanfromjuno:
I finished working on my arc ls hybrid seconds. I lost one. DO NOT USE CRAZY GLUE on the arc circuit board to hold it down. I pushed down on my circuit board with toothpicks while letting the crazy glue bond the back of the board to the aluminum disc heatsink. Some crazy glue got on the circuit and the light doesn't work.

However the other two arc ls hybrids worked. One I completely weatherproofed. The other one I did a mediocre job because I could not get the bezel loose.

For the completely weatherproofed arc,this is what I did. Unscrewed the bezel, sometimes heat is needed from stove or whatever to undo the locktite; mine just openned with a twist. The collimator lens is held by a ring screwed behind it along with a plastic washer. Unscrew it; I used two jeweler's screwdrivers to stick in the two holes on the ring to turn it. Place the collimator, ring, washer and bezel aside. With 2 AA batteries in my holder, I twisted the flashlight on and kept on twisting and the circuit board pops out the arc's head. The rest of the head and the battery holder can be put aside. There is a gold strip along one half of the circle of the circuit board on its outside. In my arc silver conductive epoxy was dabbed on this gold strip and smeared out to the housing wall and along the edge of the heatsink disk and around to the other side of the circuit board where the batteries face and this silver epoxy ended on the outer gold strip on the circuit board on this side as well. Obviously, someone was trying to circumvent the housing and just run the current through the epoxy. Without the epoxy the current would have to travel through the head to get to the other gold strip. I took my silver epoxy kit and mixed up enough. I used toothpicks to cover the entire gold strip and worked it out over and to the other side coverring the other gold strip for the same length as the original gold strip. Be careful not to make the outer side of the heatsink to lumpy or it won't fit back in the head; smooth it with the toothpick, but you could always sand it when dry later. Then I mixed up some JB Weld nonconductive epoxy cold nonconductive weld and I used toothpicks to apply this carefully over the entire circuit board except for the portion coverred by silver epoxy and except for the luxeon bulb and I did not put this on the outer side of the heatsink washer because this epoxy is nonconductive and will ruin the heatsink; I left the outer edge bare aluminum except for the portion coverred in silver conductive epoxy. I also left the battery gold cobalt contact bare of course. But no circuit board is exposed at all any longer to moisture. My arc ls hybrid has now been POTTED.

Then I took lens crafters moist eyeglass cleaning towlettes in sealed tinfoil pouches and I polished the collimator spotless. Then I took my GE silicon II sealant and I applied it to the inside of the bezel that is the bezel's inner metal lip that buts against the collimator. YOU MUST APPLY A HUGE WAD of silicone not a little bit. It will get all over don't worry. It is the only way to get a good seal, trust me. Put in the collimator without getting fingerprints; one side of the collimator has a tab and one side of the threads in the bezel has a space running down the bezel for this tab cuttin a lane down the threads. THese must match up or your collimator won't fit and you drop it getting finger prints all over it. Put washer back in and screw ring tight. Silicone should be oozing out front. Get lots of lenscrafter premoistenned paper and scrub off the silicone and all marks leaving the front spotless EXCEPT FOR A NICE FLUSH BAND OF SILICONE between the bezel and the collimator. NOW IT's more waterproof than the rev2 possibly. Now when ciruit board dries in maybe 3 to 4 hours put it in the head. Then get the assembled bezel and look at its threads. Notice the lip of metal at its top that is on the collimator side of the threads. Apply LOTS of silicone to this entire lip surface LOTS. THen screw it down tight. Get toilettes again and scrub spotless except for a flush band of silicone in this bezel and head junction. Once again now this should be as water tight as the rev2's one piece body. Even If water manages to get in the circuitry is potted and only steam should collect on the collimator or the batteries should go dead or it could pit the aluminum battery housing threads because aluminum dissolves in saltwater with electric current. However, the circuit board and luxeon should be impervious as long as you potted the entire thing which takes a lot of patience to do carefully and thoroughly.

I turned it on and it works beautifully. It's even better than before because my collimator is spotless like a diamond.

My other arc ls's bezel would not come off. So I potted the battery holder side of the circuit board. I smeared silicone on the outside of the bezel and head junction working it into the crack. I also smeared it on the bezel collimator junction and cleaned off all of the collimator with the moist eyeglass toilletes except for a narrow band of sillicon I had to leave on the collimator for the water seal. THis arc is downpour prood.

The other arc ls might even be dive proof.

I screwed up with the first arc second. NEVER use crazy glue with circuitry. It screws it up unlike epoxy. You can pot the whole thing in epoxy and no problem. Get a little bit of crazy glue on it and its dead.

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>>. She gets violent with innanimate objects when she gets frustrated<<

i found that very funny...

sounds like they might make pretty good pets after all. about how big is she now?

i wonder what it is about crazy glue that messes up circuitry...?

THanks for the offer but I think I'm just going to keep the damaged unit on my desk. I also scratched the circuit board trying to remove the crazy glue. It's irreparabel because of this.

As for the idea of the premium le line of arcs that will be potted and perfectly water sealed by arc if they decide to do this, I have another suggestion. Instead of your tailswitch which is fine for a production model but not a luxury model with all the work done to the head, why don't you sell it with a set of battery holders making SURE TO INCLUDE AN 2AA BATTERY HOLDER FOR PEOPLE LIKE ME WHO WANT TO USE NIMH RECHARGEABLES. Peter Gransee, the only reason why I didn't by a surefire over your light is because surefire's can't use 2AA. They have an unsatisfactory nicad conversion unit for their flashlights which I don't like. I consider it cheap for the flshlight manufacturer to design their rechargeable flashlights such that a customer can't upgrade to better rechargeable batteries as they become available. If surefire had offered Kl1 or Kl3 with a new holder for AA batteries 2or 3 or 4 I would have bought it instead or in addition to. I saw the thread on candleforums of the guy selling homemade tubes for the kl1. But I don't own a surefire so I'd have to fork out $170 or so to get the tailcap and everything for a flashlight that has been rumorred to leak water like your arc ls does as well.

Anyways, in your luxury arc ls le line what I want to see is battery packs including the 2AA battery pack designed just for this arc and threaded to accept surefire's REPLACEMENT TAILCAP SWITCHES THAT HAVE A LOCKOUT FUNCION. HERE IS THE LINK TO THIS TAILCAP AT SUREFIRE:
http://www.surefire.com/cgi-bin/main.pl?pgm=co_disp&func=displ&prrfnbr=813&sesent=0,0
Surefire charges $33 for the full retail online store price. This is a reasonable price for a luxury model flashlight and would be much better than your production line switch, no insult intended; remember I like your flashlights and company and a true friend gives honest advice not smooth damaging lies.

Excerpt from surefire's online store on its tailcap for sale:
"Now you have a choice of Momentary or Constant-On light activation without having to rotate the tailcap of your light. Push lightly on the Click-on Lock Out Tailcap for momentary activation, push harder to "click" the light into Constant-On mode.
High quality aerospace grade aluminum construction, featuring precision machining with the addition of a lock-out feature and a raised rubber lip to prevent accidental discharge of light during tactical operations, transportation, or storage.

Will fit the following SureFire models:
6P Original, Defender D2/D3, Centurion C2/C3, CombatLight Z2/Z3, M2, M3/M3T, M4"

My possum is slightly larger than a large housecat now and around 12 to 15 pounds. I forgot to mention that they stink. They have a scent gland that constantly is leaking a foul smell. But, she's like part of the family so I don't mind. Other people might.

I forgot to mention, Peter Gransee. If you add the new battery packs for the surefire caps, please make sure the threaded junction between them and the battery holder is sealed at least with an Oring. I have never seen a surefire replacement cap so I don't know if they include an oring in the tailcap or if you need to manufacture one into the battery housing. I don't want to have to silicone paste the tailcap into a luxury model arc which should be perfect.

Also, please hand select luxeon bulbs for the luxury arc dumping the rest into the production models. As soon as the 5watt luxeons become flaw proof and their lifespan can be increased to at least 20,000 hours then please make both 1 watt and 5 watt models available. Thankyou.

By the way, I really love my arc ls hybrid second which I now have made flawless as what I always dreamed a led flashlight could be from all the reviews I read at the ledmuseum, especially on lambda's ill pill. My arc is waterproof, weatherproof and very convenient. I JUST WISH SOMEONE MADE THIS QUALITY OF A UNIT FOR AA NIMH RECHARGEABLE BATTERIES OR C OR D RECHARGEABLES FOR THAT MATTER THAT CAME PREMADE WITH NO TINKERRING OR SPECIAL ORDERRING REQUIRED. JUST CLICK ON THE ORDER BUTTON ON THE ONLINE STORE WEBSITE AND NICE AND SIMPLE.

if he did offer models like that, they would probably be at least $80 more. it would be nice, but it really isn't plausable at the moment. arc is currently looking into the kroll switches, but custom ones would cost a lot of money. there are plans for a 5w module called the ls3 (this is assuming lumileds ever gets the 5watter fixed), but until then, the ls3 is suspended indefenitely.

what i really want to see from arc (and every other flashlight manufacterur in the world) is a sapphire crystal lense.

Coyotes are not an endangered species (just the opposite) so the feds don't import them. Coyotes import themselves. They think Muffy (dogs) and Fluffy (house cats) are very tastey.

We have them living in downtown Chicago, in the parks and in all the surronding areas.

Good job on the Arc

Hi Guys,

I'd like to throw my two cents in, spread out on a few comments so their value is really suspect

Rothrandir,

The LS2 will have a lexan lens so the design is very likely compatable to DIY upgrading with a sapphire lens.

Ledfanfromjuno,

A couple of comments:

1) Nice detailed work!

2) In my experience, cured silicone makes a great, long lasting gasket which is impervious to most environs, allthough subject to tear. SIlicone's adhesive qualities are weak with the exception of bonding to glass. The best silicone seal is when a compression is applied to the cured silicone

3) The Z48 "clickie" switch from SF is a fantastic tail switch but its mass and size is about that of the Arc LS head itself. Incorporating this switch with an Arc power pack will greatly increase the overall size of the light.

4) I too have heard of E2 bezels leaking but I have not heard of the Kl1 having similar problems. Granted, the KL1 has not been out long but two facts have me inclined to believe that the KL1 will be water proof, if not pressure proof. PK stated in a SFDB thread, when asked, that one of the design intents of the KL1 was resistance to water intrusion. I have unsuccessfully attempted to take a KL1 apart. I ended up totally destroying the part as I was unsuccessful in breaking the thread seals on the components. From what I could see, there may be a redundancy in that custom gasskets and seals have been employed along with the the thread sealants. In defense of my ability to take the lights apart, I have successfully taken apart a half dozen Arc LS's as well as other SF bezel assemblies. The KL1 is put together pretty darn well!

5) I took my Arc LS's apart due th the flex failure. They depend on a mechanical contact between the PCB and a shoulder within the threaded junction sleeve that joins the head to the power pack to complete the ground path. The head and sleeve are screwed together and a thread locking glue (Lock-Tite?) is used to keep the sleeve and head from unscrewing. Unfortunately as a result of thermal expansion/contraction cycling, I believe this mechanical contact becomes tenuous and the additional compression load of the battery in turning on the light can open this contact ( flex failure). My solution to this was breaking the thread lock so I can re tighten the sleeve to head when needed. However, I don't have a waterproof flashlight. I think your solution is more elegant with obvious additional advantages. If I followed your posts correctly, I believe you have upgraded from a mechanical contact for ground path to a permenant ground path via the electrically conductive epoxy. Good Job! Because of the high coefficient of thermal expasion (CTE) of Al, care must be given to the selection of potting and bonding materials as they likely must move and be elastic to the changing dimensions around them while still adhering to the components they are contacting. With one possible exception of the silicone, it sounds like you have done a fantastic job of improving your Arc! Even the silicone is probably fine; I am just leary from reparing too many leaks on boats due to the use of silicone as a sealant.

Nice job and great discourse!

- Don