Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Situation: After the apparent delicate nature of Kai's Buckle Lights up to revision 3, V4 was meant to be "bullet" proof.

I've had it on my keychain for a while now and though the exterior did stand the abuse the electronics failed after a simple battery change. Having read at least one other notice about a dead v4 made me wonder if there are other failed ones out there.

Problem: What I found the be the problem is that the Cree is only held to the "pill" by a little silicone glue and since there is NO insulator between the led and the aluminum reflector once the glue loosened the circuit shorted out and effectively died.

Fix: If you own a still working v4 buckle light you should consider to open the head (it is glued but will screw off if you really try) and put a bit of insulating material (cree shim) between the led and the reflector. This may also help holding down the led toward the pill.

Request: Please vote wither your v4 (maybe v5) is still going strong or has already failed

Side note: I've ordered sku 07881 from dealextreme to repair my v4. I'll post if it fits the pill once it arrives.

http://www.dealextreme.com/details.dx/sku.7881

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

I've been through 2 V4's. One for me and one for my friend. Both died whitin a week.

-Mine died after a 1.5m drop along with my car's keys. Dissarmed it and found the emitter functional. My current L0D has been dropped more than 30 times and it is still alive.

-The one I gave to my friend died because of my fault. I was kind enough to provide him a 10440 cell for ultra brightness... and

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

My guess for the dropped one is that the LED became loose and made contact with the reflector. The spacing between them is extremely small and you wont notice any rattling. The emitter on my failed one is still working.

I hope Kai added some shim/insulator with the v5 but I wont bet on it. So for all owners my advice to add some insulating material stands

Maybe we can get Kai to offer replacement circuits

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

no insulator on the V5 I just received. There will be soon though!

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

richardcpf said:

-The one I gave to my friend died because of my fault. I was kind enough to provide him a 10440 cell for ultra brightness... and

Click to expand...

the spec for the Q5 V5 indicates 10440 compatibility.

anyone tried a 10440 in their V5 yet?

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

I voted still going strong. I bought a V4 around the time it came out then gave it away, but I would probably know if it had failed. Besides, it worked fine for a month at least before I gave it away.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

bigbear said:

the spec for the Q5 V5 indicates 10440 compatibility.

Click to expand...

Where do you see that? It's kinda unclear on the site. It never really said Li-ion compatible. I'd like to know before I fry mine with one.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

I didn't vote because I'm still on my version (1) Buckle light. It did need a little bit of aluminum foil in the tail cap, but I've been using it about 10 times a day - every day - for the last 2 or 3 years (when it first came out) without any problems. I love the smaller form factor and the tail shape (which allows nice between the lips holding.)

By the looks of them I would rather spend twice as much and buy a AAA Fenix than the new KD buckles.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

I've had 4 KD buckle lights on my keys over the last two years... and not one of them has died. The new one, V5 they say is potted, which should add quite a bit of reliability to it. I'm carrying a KD V5 XRT and a MJP Extreme Rebel now. If the lights go out and someone else needs a light, they will get the XRT.

This poll probably has a lot to do with how many keys are on your keyring. How heavy are your keys and what is the odds that the buckle light will hit the ground first if your keys do fall? If it lands on a key, that is a cushion to the landing of your light.

It's really not much dimmer than the V4 one I have, but offers 4 times the runtime. I would like a light much dimmer than the XRT, to give as much light as an E01 or less with a much better color beam. Maybe he can make an XPE buckle that is smaller.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Casebrius said:

Where do you see that? It's kinda unclear on the site. It never really said Li-ion compatible. I'd like to know before I fry mine with one.

Click to expand...

my bad

i didn't quite read the spec clearly at http://www.kaidomain.com/ProductDetails.aspx?ProductId=5628. it made a reference to 10400 but my brain somehow parsed it as 10440 lithium.

i have two KD Q5 V5s, a MAX and a RT. both are on (separate) lanyards which i EDC on an alternate basis.

i also have a Fenix E01 which is attached to a huge bunch of keys. (Pic -> http://www.bigbear.org/inc/20090103-edc-448x336.jpg)

so far both KDs still going strong. i have dropped them both before onto concrete from a height of about 1.5m.

the only thing so far "wrong" with one of them is that the "head" bit containing the reflector and lens is now actually untwistable, when the other unit appears to be glued or stuck.

i haven't gone as far as trying to apply force to twist the glued|stuck unit.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

I have 2 Buckle with a Seoul emitter, V3 I believe. Both still running, haven't been dropped. I did put a 10440 in one of them and it will no longer run with a AAA. It did not burn out completely. It will run with a 10440, but it's not in direct drive, because it shows about 70lm. This is just fine with me, doesn't have the 150lm plus and 10 min runtime it would in direct drive.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

My V5 came in today. There's no insulation between the LED and reflector, but there is a step on the reflector that rests on the Cree ring pushing down on it when the cap is screwed on. I took the reflector out and placed it on the LED and it seems it would prevent contact with the pos and neg traces on the emitter. You could put something non-conductive between to be sure. I don't have a V4 to compare to.

No glue on the head cap, comes apart easily. Tried a 10440 for about 30 sec, still ticking. It's only about 20lm brighter with the 10440, not worth it. About 65lm with the NiMH.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Nake said:

About 65lm with the NiMH.

Click to expand...

is this with the RT version?

i'm curious as to how to-spec the advertised 60 lumens on the RT and 100 lumens with the MAX are.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

bigbear said:

is this with the RT version?

i'm curious as to how to-spec the advertised 60 lumens on the RT and 100 lumens with the MAX are.

Click to expand...

I have the MAX version.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Nake said:

I have the MAX version.

Click to expand...

i'm going to be curious again and ask how you measured the 65 lumens output, and with what parameters?

thanks!!!

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

bigbear said:

i'm going to be curious again and ask how you measured the 65 lumens output, and with what parameters?

thanks!!!

Click to expand...

I use a Quickbeam type lightbox. Not an IS, the numbers are approximate, but better than an eyeball meter. Here's a link. Check out his review site, there's good info there on lumens. http://www.flashlightreviews.com/features/lightbox_output.htm

The numbers I get are also close to what member "chevrofreak" shows.
http://lights.chevrofreak.com/runtimes/

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Wow, a 40% failure rate. I voted that mine is still working but it has only been used a few hours since I got it many months ago. I am now wondering if I used it on a regular basis if my vote would have been different.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

Had a v4 for many months now, use it daily. Still going strong and working perfectly despite dropping it a few times. Some slight signs of wear where the ring is connected. Threads and all still excellent, too.

Re: Poll: Failure rate of Kaidomain V4 & V5 Buckle Lights. Also warning notice + fix

dropped my V5 MAX on steel deck last night from 4 ft., landes directly on head - no wahalla!

Driver replacement for V4 Buckle Light

Yesterday the new driver circuit arrived: http://www.dealextreme.com/details.dx/sku.07881

I have to say it's not a drop-in replacement as the dimensions are quite different from the original driver.

The diameter the driver is exactly that of a single AAA battery. Therefore the driver will not make contact with the battery tube when screwed down but slide into the tube. I worked around that by making a small aluminum ring that fits around the UI-board and makes contact to the battery tube and is wired to the negative terminal of the driver. As the driver is quite high the bottom part slides into the battery tube when screwed down. Luckily the battery tube and spring hold enough extra space to still make it fit.

If anyone needs better advice I could make a drawing on how it all fits together. I had to built the contraption twice as the first one got a little shoddy during the try-out phase. The second version seems to work quite smooth though.

Of course I added a isolator between the led and the reflector. Something which I still recommend to all buyers of this light to prevent accidental bricking.

Now I have a 20 mode AAA twisty... Good thing is that is spares me from buying all three versions of Kai's brainchild as I now have all those settings in one light plus a plethora of blink modes

High level is actually quite high, noticeable brighter than the v3 and the low levels are pretty low too.

Looking at the poll the failure rate seems rather disappointing to me. I don't understand why Kai doesn't at least offer a replacement circuit for these light. As the one I used doesn't seem to be in stock anymore.