How sensitive are incandescent bulbs to knocks?

Jasmes

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I know that it is possible for an incandescent bulb to be blown out by an impact/shock, but how likely is that to actually happen?
 

Brighteyez

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Yup, done it lots of times. Doesn't take much, especially if the bulb is illuminated. I've done it by just moving an illuminated lamp.
 

PhotonWrangler

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It depends on several things -

- The design of the filament supports.

- How hot the lamp burns.

- The running hours on the lamp (older filaments are brittle).

- The distance from the filament to the bulb's envelope. If the filament touches the envelope while it's lit, it blows out.

Halogen lamps can blow out REALLY easy if they're vibrated while operating.

There are lamps that are designed for high vibration environments that have a ruggedized filament and support system. I think the G-E line is called "rough service" lamps.
 

Jasmes

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PhotonWrangler said:
It depends on several things -

- The design of the filament supports.

- How hot the lamp burns.

- The running hours on the lamp (older filaments are brittle).

- The distance from the filament to the bulb's envelope. If the filament touches the envelope while it's lit, it blows out.

Halogen lamps can blow out REALLY easy if they're vibrated while operating.

There are lamps that are designed for high vibration environments that have a ruggedized filament and support system. I think the G-E line is called "rough service" lamps.

I'm mostly wondering about the P61/91 LA's
 

hburner

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I was working on the wifes car one night using the P60 in a G2 and dropped it after it had been on for about 10 min. the light went off, came back on and then died. That sucked!

I belive that the P60 is one of the weakest lamps by SF as far as their holding up in knocks or drops. I have instflashed a couple by using them with the 3.7v batteries that have the protection that pulls them down to 3vs. Never have I had a P91, P90, or P61 go out on me from dropping or banging them around. I believe that they are a lot mor stout. But thats just me. The Wolf Eyes are pretty tough also.
 

Jasmes

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does a shock isolated bezel protect the bulb enough to be worth the money?
 

jar3ds

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Jasmes said:
does a shock isolated bezel protect the bulb enough to be worth the money?
well.. honestly... if your that concerned w/ bulbs being fragile.... just figure out an LED solution...

i've only really messed with the ROP bulbs... and i haven't got one to fail yet....
 

LTXC^3

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Jasmes said:
does a shock isolated bezel protect the bulb enough to be worth the money?
In my experience, probably. I use a M2 shock isolated bezel and a Z48 clicky on my C3. But, without any experimentation nor comparison to a standard "control" bezel or tail-switch in all of these drops, I'm hesitant to claim they necessarily saved my P90s. Yet, I definitely believe they do reduce bulb shock from both front and rear impacts, and in some cases perhaps they prevented filament damage that might have occured without them. During my ongoing collection of bezel nicks, the first P90 died during one of the first few drops, but after many more bezel-plants from inches to waist height impacting various surfaces (excluding concrete), the second P90 surprisingly still works fine. The M2 bezel and Z48 are worth the added cost to me because they have increased my confidence in the C3's shock resistance, thus dependability, and IMHO might have saved a few P90 LAs. Good luck.
Alec
 
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Jasmes

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LTXC^3 said:
In my experience, probably. I use a M2 shock isolated bezel and a Z48 clicky on my C3. But, without any experimentation nor comparison to a standard "control" bezel or tail-switch in all of these drops, I'm hesitant to claim they necessarily saved my P90s. Yet, I definitely believe they do reduce bulb shock from both front and rear impacts, and in some cases perhaps they prevented filament damage that might have occured without them. During my ongoing collection of bezel nicks, the first P90 died during one of the first few drops, but after many more bezel-plants from inches to waist height impacting various surfaces (excluding concrete), the second P90 surprisingly still works fine. The M2 bezel and Z48 are worth the added cost to me because they have increased my confidence in the C3's shock resistance, thus dependability, and IMHO might have saved a few P90 LAs. Good luck.
Alec


Thanks, I was pretty excited about getting my first incan but then I thought of how I'm accustomed to the insanely indestructable Inova X5 as my EDC, so I wanted to get some idea of just how much I'll have to baby this thing in comparison.

I guess I'll just need to be gentle with it, and maybe pick up a shock isolated bezel at some point. :cool:
 
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dyyys1

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To be honest, I'm kind of surprised at how many people say they have broken their incans. I have never broken a bulb in a flashlight, and i've dropped my incans many times. My minimag has hit the ground lots of times, and my A2 has hit the ground pretty darn hard several times. I suppose it's possible to break an incan, but I've never really babied mine. Don't forget that the SF E2D is an incan and it's designed to strike things.
 

LTXC^3

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Hey, Jasmes
SFs 2004 Illumination Tools catalog (pg.24) illustrates the term "strike" in the context SF uses in reference to their E2d Defender, M3, and others. I assume the current catalog does too. It might be helpful.
I agree about your X5, amazing! Also, comparing it's LEDs to a P90/91 LA, you trade-off LED longevity and superior shock resistance for a much brighter incandescent, but with much less operational life span. I finally accepted carrying a spare P90 LA and batteries in a SC1 when hiking at night, along with a good backup LED similar to the X5. Good luck!
Alec
 
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Alin10123

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I agree with the folks here in that the design of the bulb is important. Some bulbs are built more robust than others. But the less than robust bulbs probably run more efficient. Of course, that's just a theory. Haven't been in the hobby long enough to figure it all out yet.
 

Jasmes

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LTXC^3 said:
Hey, Jasmes
SFs 2004 Illumination Tools catalog (pg.24) illustrates the term "strike" in the context SF uses in reference to their E2d Defender, M3, and others. It also explains shock isolated bezels. I assume the current catalog does too. It might be helpful.
I agree about your X5, amazing! Also, comparing it's LEDs to a P90/91 LA, you trade-off LED longivity and superior shock resistance for a much brighter incandescent, but with much less operational life span. I finally accepted carrying a spare P90 LA and batteries in a SC1 when hiking at night, along with a good backup LED similar to the X5. Good luck!
Alec

Does it explain how the bezels work? I've always wondered, I should order one of those catalogs I guess.
 

a99raptors

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I dropped two G2s and ruined both P60s on two separate occasions. Just fell down on concrete from 4 feet up. They still lighted up, but the hotspot had an ugly black hole in each.
 

zespectre

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a99raptors said:
I dropped two G2s and ruined both P60s on two separate occasions. Just fell down on concrete from 4 feet up. They still lighted up, but the hotspot had an ugly black hole in each.

Haven't had that happen with a p60 yet, but did the same to my MagCharger a while back. The filament bent into this LONG "U" shape. It didn't break but man the beam was off center and UGLY after that.
 

LTXC^3

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Jasmes said:
Does it explain how the bezels work? I've always wondered, I should order one of those catalogs I guess.
Hey, Jasmes
I edited my previous post. My mistake, the SF 2004 catalog only mentions shock isolated bezels on their special operations series, but does not explain how they work. I'll take a shot at it. Against the M2 bezel round interior wall rests a soft black (silicone?) flexible spacer (5-6mm wide) and a very thin metal ring formed to hold the the Pxx LA reflector rim. They fit between the bezel lens and the front of the Pxx lamp assembly, serving as a cushion between them. Attached to the back end of the Pxx LA is a spring. Together, the spacer and spring create a suspension system, isolating the LA from direct contact with the bezel wall. A drawing would really help about now. Check out www.surefire.com SF claims that weapons mounted SIBs enable their filaments to withstand repeated recoil. www.Lighthound.com stocks them. Good luck!
Alec
 
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Jasmes

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LTXC^3 said:
Hey, Jasmes
I edited my previous post. My mistake, the SF 2004 catalog only mentions shock isolated bezels on their special operations series, but does not explain how they work. Inside the M2 bezel, there is a soft black flexible spacer (silicone? rubber?) filling the 5 or 6 mm space between the interior lens retainer ring and the front of the Pxx lamp assembly, serving as a cushion between them. Check out www.surefire.com SF claims that weapons mounted SIBs enable their filaments to withstand repeated recoil. Lighthound stocks them. Good luck!
Alec

Well I ordered the catalogs anyway. :cool:

So the bezel just gives the bulb a little cushion eh? I'm surprised there isn't an easy DIY mod to a normal bezel to do that. :confused:
 

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