Ti Arc-AAA: fix for sometimes fails to light

This might be helpful for some people:

The new Titanium Arc-AAA allows for easy swapping of the light engine (LED and driver PCB). This makes it somewhat future-proof since you can easily upgrade to brighter LEDs as they become available. The Titanium housing can last for generations so it makes sense to make it easy to service.

The downside to giving the customer access to the driver is that it can get rougher handling than a driver sealed with epoxy and not able to be removed.

The PCB is plenty tough as long as you don't remove it. I have already posted about how you should be careful when removing/installing the PCB. I have seen some pcbs broken by rough handling. For example, if the pcb is too snug and you don't size it to fit your head, it is going to be really hard to get it out of the head later. And this could result in having to use a lot of force on the pcb to pop it out. I have seen the black diode popped off the board from tools being inserted into the epoxy fill holes. This is also detailed in earlier posts.

My personal carry Titanium AAA (GS) I have had for awhile now, I had one before we began shipping of course so it has a good amount of use on it. my pcb has been ground down so it pops out of the head very easily. About a month ago however, it started only coming on intermittently. I checked all the usual stuff and didn't find any problems. The circuit was properly grounded, the diode was in place, etc. It took awhile but I found that the yellow capacitor soldered to the LED leads had a cracked solder weld. The crack was hidden so it looked fine on visual inspection and would work fine electrically until it was placed in the head (which caused it to flex enough to create an intermittent). The fix was simple, reflow the solder. It has a made a big improvement in the operation of the light. Until I had found this, I was starting to leave the light behind because I didn't feel like I could trust it and I didn't have the time to figure out what was wrong with it (I just used my Arc6 instead). But I finally set down and tested it more in depth and that's how I found the cracked weld. So if you have a unit that is failing to come on every once in awhile and you have checked everything else, trying reflowing the solder joints on the capacitor.

peter

Gransee said:

This might be helpful for some people:

So if you have a unit that is failing to come on every once in awhile and you have checked everything else, trying reflowing the solder joints on the capacitor.

peter

Click to expand...

If I had this problem (which I don't) I would hope that I could send it to you to be fixed. My skill with a soldering iron is not up to be trusted.

Does having the LED drop into the head rather than the epoxied version affect the waterproof qualities, ie: 100 feet, that exist in the standard aluminum AAAs?

I wonder if it could make sense to pot these circuits in thermosetting (hot melt) glue instead of epoxy. That would protect the circuit board from vibration while still leaving it possible to replace/upgrade the circuit board by heating up the head til the glue melts. You'd give up the feature of interchangeable light engines (removing one would be a messy and destructive operation) but at least it would be possible to service the light this way. Multiple LE's seems like an overrated feature to me anyway. I'd rather have separate lights for the separate LE's.

mridude,

Not epoxying the LED and electronics moves the waterproofing responsibilities to the front window seal, which the epoxied version does not have. As you know, this front seal on the Titanium Arc-AAA consists of a sapphire window sandwiched between 2 o-rings. We haven't tested it to its maximum depth but figure it is good for at least 100 feet no problem.

So to answer your question, solid epoxy is hard to beat for protection, but using double o-rings is more than sufficient for the depth rating.

paulr,

interesting idea. We still are seeing pcbs being damaged by the customer (always while swapping the light engine) from time to time although it has gotten better.

As far as why the ability to swap Light Engines is valuable: it is not so much about having different beams or colors but more about being able to take advantage of brighter/more efficient LEDs as they come out. LEDs double in efficiency about every 2-4 years and this will likely continue for 5-10 years.

One of reasons people who like cutting edge LED flashlights have kept buying new models is because LEDs keep improving. With the ability to swap out the Light Engine, we can now minimize the upgrade cost. This hopefully means more people can enjoy the best technology.

peter

btw, it has been over a month now and the repair to my light at the beginning of this thread is still going strong. This Ti GS is my every day carry.

peter

Any possibility of just selling the fully potted heads separately or would the cost be too high?

No, it wouldn't cost too much. The problems we have seen are from removing and reinserting the light engines. Potting would make them a bit tougher but it would mostly help by making it impossible for the user to swap the LE. however, I think the ability to change the light engine, LED, etc is a neat feature and would like to keep offering it.

peter

It would make the light slightly larger but maybe you could have a potted LE in a slug that screws into the light. That would be totally waterproof too. I think some existing lights are like that.

Yes, my suggestion of hot melt glue was with the idea of upgrading the led when a new one comes out in a few years. I don't see that much usefulness to swapping LE's around to change colors etc. It can be more like replacing the engine in a car, i.e. not a casual operation at all, but doable for quite a bit less cost than buying a new car. McGizmo has done something like this with his version of the Sapphire, I think, staking in the DS LE so that it is still removable, but only with difficulty.

Some observations of my Ti AAA.

Flickering, dimming ...sometimes to the point of going out. The action on the head would be best described as 'scratchy' when twisting on and off. when the light appears to be dimming or flicking I tighten it a bit more but I fear that I maybe damaging something as it feels to be socked way down to stop the flickering. I have one black/sponge O-ring (that came with the light ... I got the two LED kit version) installed inside the light.

It really feels as if I'm tightening this thing too much to keep a steady beam. I have a queezy feeling that I may soon crack/dent something...which goes first...the LED or the battery contacts?

I've seen some postings about cutting the O-rings in half, inserting a wedge of paper...etc.

All in all, if I had to take one of my Arc AAA's along as a needed personal carry in some sort of emergency I'd probably go with my aluminum AAA-P. It's been faultless so far.

Mridude, I sympathize. The kit is a bit more hands on than the stock AAA. Even so, it can be a very reliable light. The action should be smooth and the light shouldn't flicker. It is hard to tell from here what is going on with your particular unit. You could send it back to us if you want or you could try checking the LE for loose solder connections. The threads may have some contaminant in them. Flush them with solvent and relube. My titanium AAA has been very well behaved for several months now since I resoldered the capacitor. I took it camping last week and it was my primary go to light. Prior to the repair I saw the light as unreliable. After the repair my attitude towards it changed and now I use it all the time.

peter

Gransee said:

Mridude, I sympathize. The kit is a bit more hands on than the stock AAA. Even so, it can be a very reliable light. The action should be smooth and the light shouldn't flicker. It is hard to tell from here what is going on with your particular unit. You could send it back to us if you want or you could try checking the LE for loose solder connections. The threads may have some contaminant in them. Flush them with solvent and relube. My titanium AAA has been very well behaved for several months now since I resoldered the capacitor. I took it camping last week and it was my primary go to light. Prior to the repair I saw the light as unreliable. After the repair my attitude towards it changed and now I use it all the time.

peter

Click to expand...

Ahhh, well, frankly I wouldn't know if the LE had loose solder connections if it told me. I'll unscrew it and look for the obvious I suppose.

Interesting point you had made about the saphire lens giving the unit it's waterproofness. I had mentioned some time ago in another thread that I believed that $15 for the standard aluminum head was better for me than $70 for the titanium with the lens. I would assume that even thought the other LE in the Ti kit w/ the Aluminum AAA head would indeed fit and operate on the Ti body... you would NOT have a waterproof light....right? How about if I were to epoxy the other LE into the the aluminum AAA head...waterproof?

The epoxy is required with the aluminium head for waterproofness.

peter

After rereading all of this I am starting to think that perhaps I should send the Ti AAA back, with the other unused LE that came with the kit... eat the $70 for another Ti head/lens and let you install them and trouble shoot the LE, which I believe was the GS, not sure, that is flickering.

Quickly again: Where to send this. How, as in UPS vs Fed Ex vs the pony express... insured.

Payment. I know that you don't like checks or cash via the 'mails'. I'm not a member of Paypal. How do I purchase the other Ti head/lens online and have it 'hook-up' with my light when it arrives?

Address:

MTD LLC
3101 N. 33rd Ave
Phoenix, AZ.

Fedex or UPS is preferred since it is more reliable but USPS is ok. default insurance with Fedex, UPS.

I recommend paypal. the account is free and is easy to use.

peter