Hotwire Hazards. Yikes!

[Ginseng]

I was prowling the property with my Mag3D/WA01185/10AA nimh tonight and lighting things up pretty well. All of a sudden, I heard a pop come from my flashlight and then a fraction of a second later, the light went out. Luckily I had my trusty L4 ready. I made it back inside and this is what I found...

On the left is a shot of the front of the bezel. The entire interior of the reflector area is coated in a fine, dusty haze. The sparkly stuff at the bottom of the lens are fragments of the blown bulb capsule. My reflector is a Carley 1940 coated aluminum unit and the chunks of glass blew out with enough force to rip chips out of the coating down to the bare aluminum. I'm surprised but grateful that the Flashlightlens UCL survived without any damage. A quick wash of all dusted parts with soap and water took the dust and glass fragments right off.

On the right is what's left of the mighty '1185; a charred and blown filament and the jagged remnants of the aluminosilicate glass capsule. There's more of the fine dust coating the bulb retaining collar. I think that dust is vaporized tungsten from the filament. I believe this is so because there was still light coming from the head for a fraction of a second after the "pop".

Well, there it is. Another thrilling rush that can only come from insanely overdriving massively powerful bulbs. /ubbthreads/images/graemlins/grin.gif I wonder what it's gonna be like the first time I blow one of these...

Wilkey

 

[PaulW]

He he. A little fun in the dark, eh? I'm glad no one was injured.

The remains of your bulb look like mine did when I had a similar explosion. I had been running a bi-pin WA 01185 in a Carley 912 socket in my Mag 3D. After it blew, the light sounded like a baby rattle when I shook it. What I found interesting was that even the UCL was damaged. Even though it was still intact, there were a few pock marks in it.

I thought that the problem was the socket-adapter, because it was blackened by the calamity. It happened at a run-time of 5 minutes. When I use potted bulbs, I get 10 minutes easily with no mishaps at all. How long had your light been on when it popped?

I am beginning to wonder if we need to exercise more caution with these lights. I calculate your light was dissipating between 32 and 36 watts when it blew.

Paul

 

[PhotonWrangler]

According to a footnote from an old G-E halogen lamp catalog, that would be called a "non-passive end of life characteristic." /ubbthreads/images/graemlins/icon15.gif

 

[Ginseng]

The light was on for about 6 or 7 minutes with a total runtime of about 22-25 minutes on that bulb. My sense is that 10AA is perhaps just a tad over the hairy edge for this bulb. I now rest the freshly charged batteries and discharge them for a minute or two through a CA809 before I run the 1185 on them.

Wilkey

 

[PaulW]

Wilkey,

You may want to consider reconfiguring the reflector-bulb interface. For the 1185 I allow the reflector to nestle down on the bulb flange, using the appropriate number of spacer-washers in between to properly focus the bulb.

That makes it fixed focus, and I don't know for sure if it helps the heat problem. But I believe it does -- that it improves the transfer of heat from the bulb to the reflector. The heat is then transferred to the head as it moves forward toward the lens.

Paul

 

[Sway]

Wilkey,

I'm glad you’re able to report back from that one, guess you will be penciling in the eyebrows for several weeks now /ubbthreads/images/graemlins/hahaha.gif /ubbthreads/images/graemlins/naughty.gif

For some reason I don't feel so bad about killing the TWAK anymore /ubbthreads/images/graemlins/santa.gif

Later
Sway

 

[drumgod]

WOW! That's impressive in a scary sort of way. I'm glad all is well. (Well, as well as can be given the circumstances /ubbthreads/images/graemlins/smile.gif)

Having seen more than one overhead projector bulb grenade, I've been wiping down all my bulb and reflectors with rubbing alchohol before assembly. Sor far so good...

Then again, I have not yet dared to venture onto the hairy edge of the super-bulbs like you guys. (yet /ubbthreads/images/graemlins/wink.gif)