WA 1331 instaboom!

[plasmaman]

Running direct, what sort of voltage level is critical?

I just blew one of my nice new 1331s from Litho.

I'm running it on 3S x 17670 and coming off the charger they show 12.85v on the DMM.

I waited a couple of hours and it only dropped down to 12.81v - so I thought OK - but BOOM.

I thought this bulb would handle the same voltage as 1166!

Any thoughts?

 

[Lurveleven]

Maybe a weak bulb? I have been running that bulb a lot on 3 x Li-Ions and haven't had a single failure yet. Or maybe you have a very low resistance setup compared to me? I have mostly been running it in Fivemegas Stinger mods (3 x 18650), but also in his FM 700L Mag mod (3 x 17670).

Sigbjoern

 

[AlexGT]

Hi plasmaman!

I am about to sell a new 1331 and a 1185 bulbs I just bought since I won't be going to use them in a 3 x C LI-ion I was planning, decided to go 1111 in a 2 C instead.

If you want them let me know $9 shipped to the states.

AlexGT

 

[LuxLuthor]

Maybe a weak bulb? I have been running that bulb a lot on 3 x Li-Ions and haven't had a single failure yet. Or maybe you have a very low resistance setup compared to me? I have mostly been running it in Fivemegas Stinger mods (3 x 18650), but also in his FM 700L Mag mod (3 x 17670).

Sigbjoern

I have that 1331 in at least 8 FM Maglites, and hot off the charger with various 3 x Li-Ion's never flashed a bulb.

 

[andrewwynn]

high resistance is the key to saving a 1331 in a direct-drive solution... a PR adapter solution for example has 215 miliohm of resistance.. a kiu solution will have about 40+35 = 75miliohm.. that's the difference of .4 and .15V drop on resistance.. of course that resistance will drop the output from 500L with a KIU and no tailcap resistance fix to 454L 10% less light.. removing the tailcap spring resistance with wire will boost the 1331 up to as much as 517L ... if you use FET switch and fix the tailcap (20 miliohm total resistance.. actually it's even less that's being conservative). a 13% gain in output.

In addition.. typical loss of 10 to 15 miliohm on every battery that is 'fully protected'.. so using PILA vs RAW LION for example.. drop another 6/100ths of a volt (doesn't sound like much but it adds up)..

the '700L' light under drives the 1166 lamp.. there is no risk of instaflash.. even with a completely fresh bat. pack, it's 12.6V.. that's what i run the 1166 lamp at continuously.. a 'factory new' '700L' light will output a nominal 312 torch lumen.. the 'M66' or the likes with 4x14670 cells will output 600.. nearly double the output.. just by cranking up the voltage on the same lamp. upgrading a '700L' to using the KIU solution and direct drive.. and fixing the tailcap resistor will bump the 312L up to 347L.. 11% increase in light output and still zero risk of instaflash.. it is an 11.6V lamp driven at a nominal 10.7V in that solution.

specifically comparing the 1166 to the 1331 in a direct-drive 10.8+kiu+tailcap fix..

The 1166 will be underdriven 11% and output 347L
The 1331 will be overdriven 19% and output 510L

and 'just for fun'.. the 1164 can be overdriven to 9.6V (107% overdrive) for 1015L from 8 cells and even 9 if done just right.

-awr

 

[Rookwood]

I blew several 1331 bulbs as well, until I figured out that the battery pack needed to be at 12.6 volts or lower to prevent instaflash. If you can't wait to rest the pack, you can use a 12V bulb to drain off a little voltage before installing the pack in your light.

Running direct, what sort of voltage level is critical?

I just blew one of my nice new 1331s from Litho.

I'm running it on 3S x 17670 and coming off the charger they show 12.85v on the DMM.

I waited a couple of hours and it only dropped down to 12.81v - so I thought OK - but BOOM.

I thought this bulb would handle the same voltage as 1166!

Any thoughts?

 

[plasmaman]

Thanks for the input guys.

Like all things in life its probably a combination - this setup is running in an FM700L which I modded to reduce resistance (Kiu and tailspring). So combined with batteries that are still 'warm' at 12.8v maybe I'm expecting slightly too much.

So I'll try again with a pack that shows 12.6v or just under - watch this space!

Hotdriver is an obvious answer I suppose........

 

[Lunal_Tic]

I'm running a 1331 in a mini 700L and haven't had any problems yet. I also have one in a regular 700L with a Kiu socket that's OK too.

-LT

 

[plasmaman]

I have now trashed 3 of my 1331s.
#1 was unfortunate but hey...
#2 was disappointing - it meant that #1 was probably not a freak.
So thought a bit and then removed the tailspring braid I had fitted to increase the startup resistance a little.
#3 fried just the same.
This is a pretty standard setup judging by replies, ie 3 x 17670 (AW's latest) and Kiu socket in FM 700L. Showing 12.63v at the pack before #3 went. Bulb cleaned with alcohol before install and untouched by skin etc.
AWR hotdriver ordered (thanks Andrew), but why am I getting this result with 1331?

 

[Lips]

I've not had good luck with the 1331 either. Blown about 4...

Better luck with the WA1111 so far, brighter too

 

[andrewwynn]

1331 is hands-down the most fragile lamp i've used.. it works fantastically well when regulated and is extremely efficient. I pretty much 'gave up' on unregulated lights.. they drove me nuts.

the 1331 lamp is a 9.6V lamp, not 10.8 nor 11.6 (like the 1166 that FM uses in the '700L')..

1111 direct-drive in a KIU w/o tailcap fix = 500L
1331 in a Hotdriver =516L... so if you have a brighter 1111.. you were doing something wrong with the 1331.. they are almost identical in output.

-awr

 

[Lips]

FM 700L = 1331 bulb


Both my 1D FM 900L Wa1111 7.2 v (2p2s) 4 x 14670 are noticably brighter than both my 1.5D FM 700L Wa1331 10.8v (3s) 3 x 16670 :shrug:

 

[LuxLuthor]

I have 6 of FM's 700L 1331's. Reading how sensitive it is, I'm glad I always used FM's stock setup with his bipin holder, rather than a KIU. Also, always used Pilas. Never flashed a bulb.

These are always my "go to" backup lights, or ones that I let friends borrow. They just always work, and have pretty bright white spot with the default setup. Really nice with the 2" deep reflector...and a whiter color that the 1185.

 

[MSI]

I'm starting to wonder if there is a batch of weaker 1331 out there, since some folks do not have any instantflash problems while others instantflash all their bulbs. When did you buy your bulbs? I bought all my bulbs in the second half of 2005 and have not instantflashed any of them, maybe the newer bulbs are weaker?

 

[cutlerylover]

I instaflashed 2 WA1185's when I 1st got my hotwire...the votage was right and I didnt understand why it happened, but I later realized that I had touched both bulbs with my fingers while installing them...a big no no I ws told, just a noob mistake on ym part...live and learn right...yeah that was an expensive lesson for me...

 

[plasmaman]

I'm starting to wonder if there is a batch of weaker 1331 out there, since some folks do not have any instantflash problems while others instantflash all their bulbs. When did you buy your bulbs? I bought all my bulbs in the second half of 2005 and have not instantflashed any of them, maybe the newer bulbs are weaker?

That's pretty much the conclusion I'm coming to. I just got mine from Greg a couple of weeks ago..........Maybe there has been a tiny spec change.

So back to 1166 for now, until AWR's hotdriver arrives!

 

[snakebite]

handling a bulb without cleaning will not cause instaflash.

 

[chasm22]

I've used 1331's with a Kiu socket in the 700L for a long time without a problem.(Well over a year) The light is my EDC and has seen a lot of freshly charged batteries put in it without a snag. There are always variations though. The simplest way to find out would be to get your hands on one of fivemega's golden ceramic sockets and use it with a stock switch. If it works OK, you're set.

AWR, I've instaflashed more 1185's than 1331's. I know they don't have the beefiest filament around, but I've dropped them and direct drive them with few problems.

chasm22

 

[cutlerylover]

handling a bulb without cleaning will not cause instaflash.

Oh...I was told the oil from my fingers could have created a hot spot that overheated the bulb and blew it? Both bulbs that instaflashed were potted WA1185's...the 1st went right out within seconds, the second one took 3 seconds but exploded completely inside the light... :thinking:

I know the current was a bit high, but I thought the fact that I habdled the bare bulb and never cleaned the oil off contributed to the explosion?

 

[Icebreak]

Instaflash and explosion are two different types of failures. One is a filament failure and the other is an envelope failure. In my opinion, in certain conditions one may cascade the other. The term instaflash used on this board means the filament failed but the envelope was unaffected.

I'm not sure what instaboom is but I was assuming that plasmaman's lamp exploded.

Fingerprint oil can cause envelope failures in lamps.

1.) Molecular change in the quartz envelope. The envelope is vitreous quartz. Sodium in fingerprint oil will catalyze its devitrification/crystallization to crystobalite. When the envelope cools, differential contraction of crystobalite vs amorphous silica cracks the envelope.

2.) A greasy hot spot can cook up and sometimes fail the envelope. Sometimes the envelope will grow a bulbous form at the point of contact.

3.) The organics in fingerprint oil will pyrolyze to char, creating hotspots on the envelope which will soften and fail at operating temperature.

I don't think the 2nd or 3rd type of failure occur with our flashlights. Those failures take place in automobile lamps and stage lights etc. I used to think that the 2nd type did but I know longer think this.

Not a fact but my opinion is:

...I don't think that fingerprint oil is the problem in most cases.

From A Race To Failure.