64440 LOSS OF LUMENS

[357mag1]

I was really impressed the first few times using my Osram 64440 with 5 IMR 26650 batteries. The last couple of times I fired it up the impressiveness was greatly diminished. It was easily out thrown by my 1185 setup. I took it apart tonight to look at the bulb and it has become frosty.

Is this normal??? I'm sure that caused the loss in lumens and subsequent drop in impressiveness.

 

[csshih]

sounds like envelope failure.

 

[LuxLuthor]

sounds like envelope failure.

I had an envelope failure once. I mailed with inadequate postage, and it was returned to sender. This may not be related however. :devil:

Overdriving bulbs leads to early failure, and this is one of the ways it shows up. Other times there can be isolated bulb defects leading to failures.

 

[357mag1]

I think csshih may have hit the nail on the head. Upon close inspection of the bulb the little nipple on the top appears to be partially broken off. Not sure when or how it happened but that may have caused the envelope failure.

Thanks for the answers. I have another bulb I will see how it goes.

 

[maxspeeds]

Are you using the 64440 or 64440 IRC? The 64440 IRC bulb has a special in fared coating that does Change color after use.

Let us know how it goes with your new 64440 bulb. As a side note, what reflector are you using?

 

[csshih]

I had an envelope failure once. I mailed with inadequate postage, and it was returned to sender. This may not be related however. :devil:

me too, see here: http://www.cpfmarketplace.com/mp/showthread.php?t=193074 :nana:

 

[357mag1]

Are you using the 64440 or 64440 IRC? The 64440 IRC bulb has a special in fared coating that does Change color after use.

Let us know how it goes with your new 64440 bulb. As a side note, what reflector are you using?

I was using the IRC bulb and the Fivemega throw master reflector.

 

[maxspeeds]

I was using the IRC bulb and the Fivemega throw master reflector.

Great combination! Try out the osram 64458 as a high output (HOLA) alternative

 

[KiwiMark]

Great combination! Try out the osram 64458 as a high output (HOLA) alternative

+1 The 64458 is my favourite bulb and I have them in 2 of my Maglites. Not so good on run time, but damn - that output is good! :twothumbs

I've run a few batteries worth through my 64458 bulbs with no sign of clouding or diminished output, hopefully that 64440 bulb was just a dud with envelope failure and the next one will last much longer.

 

[maxspeeds]

Yup, the 458 bulb is a monster,and a monster on your batteries at around a 9 amp draw rate :devil:

 

[zehnmm]

I, too, do like the 64458 90W bulb. But, it does indeed pull nearly 10amps. Very bright.

Not quite as bright, but with around 20 min. of runtime on 5xIMR26500s, is the IRC 64447 65W bulb. Stock rating: 12v, 65W, 1700 bulb lumens, 5.42amps. Overdriven at 18.7v, the estimated bulb lumens = 5050 (from Mdocod's destructive bulb test), w/ est. torch lumens at 3,283. But all this at 6.4amps in the early part of the run.

While not as bright as the 64458, it is still a stunning scorcher. I keep it around near the bedstand for the bump-in-the-night-check-out-what-is-going-on light.

Regards.

 

[357mag1]

My second bulb did the instaflash thing !!!
Not sure why as the 5 batteries were around 4.15volts each. I put the old bulb back in and it works fine just clouded over.

Does anyone know if the regular 64440 bulbs are any tougher?