How to correct PT 40 beam?

[pedalinbob]

mosy people say the PT 40 has a nice beam.

mine has a not-so round hotspot, and a corona with a lot of artifact. it has the stochastic reflector.

could it be the bulb? i am aware that i could use writeright, but i cant help but think maybe the bulb is somehow the culprit.

any ideas?

thanks in advance,
Bob

 

[txwest]

Bob,
I've never heard of anyone with the faceted reflector having this problem. If you don't have rechargable batteries, take 4, not so new, AA's & the lamp from your 3D & see what happens. TX

 

[Al]

sto·chas·tic adj.
Of, relating to, or characterized by conjecture; conjectural.
Statistics.
Involving or containing a random variable or variables: stochastic calculus.
Involving chance or probability: a stochastic stimulation.

I guess you have the "wide beam textured" reflector ... if so, maybe the filament is off center? Replace with any 4.8 or 3.6 lamp & see what happens.

 

[pedalinbob]

wow, the 3d mag bulb is much smoother. not perfect, but smoother. brightness seems similar. the spill is VERY nice. great flood with powerful central hotspot.

so, what bulb should i use to replace the original pt40 bulb? (can i leave the mag bulb in?) when i look at the original bulb, it does look off center--and the pointy part looks crooked as well.

will any 4.8v 0.5a bulb work?

many thanks,
Bob

ps i thought "stochastic" was synonymous with "textured reflector". quickbeam stated this on his site.

 

[txwest]

Bob,
For best brightness, 3D krypton bulds do nice. If you put brand new batteries in, it might pop. Consider getting the 4D Zenon bulb to run on new batteries, then when you notice it getting a little dimmer, switch to the 3D krypton lamp. TX

 

[PlayboyJoeShmoe]

I haven't blown up a 3cell bulb yet using 4AA Alkys in several different lights. My TEC40 was not bad as I got it, but with the correct (straightest) bulb it makes my buddy with an SL35X say wow!

I am always on the lookout for M*g Xenon bulbs in 4, 5 or 6 cell versions and would try a 4 cell in a heartbeat in my TEC40!

 

[txwest]

I have one I picked up at HD, & another I just got from BG. May try it out & let you know how long it lasted. I'll probably try NiMH 1st. TX

Come to think of it, it's the 3D Xenon I want to try on 4 cells.

 

[Stingray]

Bob, my 2 Tec 40's with textured reflectors both came with beams very similar to what you reported. I haven't tried any different bulbs yet.

 

[tkl]

i have a pt40 and am wondering the same thing. i'd like to replace the bulb but i don't want to take much off the run time. what would be a good medium?

 

[Owen]

Does using the 3 cell bulb reduce runtime? I figured it was just overdriving the bulb, and that bulb life might be a concern, but not the runtime(?).

 

[txwest]

Owen,
There's no free ride here. It's kinda like increaseing the horsepower in you car. Other things being equal, you gas mileage will fall. When you increase the voltage on a given bulb, the fact that it gets brighter means your drawing more amperage, shortening your run time. TX

 

[Owen]

Yeah, but...does that analogy apply here?
Increasing voltage gives the same wattage with less amperage, or gives greater output with the same amperage. I don't know flashlights that well, but I know audio equipment, and a little about how resistance, voltage, and amperage work. Increasing voltage, and in some cases, lowering resistance allows the same output with less strain on the power supply (amperage).
What makes a flashlight bulb different?

I'm not being a smart aleck. This is what makes different hobbies interesting to me, learning the how and the why

 

[Charles Bradshaw]

Put an ordinary Krypton bulb in it and you should notice a big difference in beam quality.

 

[Illuminated]

Owen,

The stock bulb for the PT40 is 4.8V/.5A. Most Krypton or Xenon 3-cell lamps I've seen and /or tried in the PT lights are rated 3.6V/.8A or higher, so overdriving them with 4-cells will push the running current up close to 1 amp. While definitely brighter, you should expect the run time to be less than the stock lamp because you're drawing close to twice the current.

I'm curently awaiting my custom potted lamps from Carley. The #817 Halogen is rated at 5 volts/.8 amps, and 8.5 MSCP of light output. Re-rated for 4.8 volts (1.2V AA's x 4) the current draw will be slightly less, but the light output and efficiency are still good.

I chose this lamp to try because I wanted an efficient lamp that would be acceptably bright, while maintaining the best run time possible. I'll let everyone know how this turns out if anyone's interested.

Merry Xmas!

John

 

[Illuminated]

As far as beam quality is concened, the textured reflector is not bad, though the spot is often a bit irregular, and there are various artifacts in the corona. IMO, still a very useable beam.

Interesting note - I tried Lambda's Krylon trick on the smooth PT "narrow beam" reflector and it produced decent results. By holding the reflector at arm's length and spraying the reflector with VERY short blasts, it was kind of like just adding a little overspray. I let this dry for a while between applications, and after (3) applications I did a fourth coat, just heavy enough to get a "wet" surface. Be careful with the wet coat, because if too heavy, it'll smooth everything out too much and you will lose the desired texturing effect. The end result was that the light texturing was finer than the PT textured reflector, and the beam was smoother and tighter in comparison, though otherwise similar. I should note that the smooth reflector (unmodified) produced a tight but very irregular beam, and not very useable as such IMO.

Hope this helps... and Merry Christmas to All!

John

 

[Owen]

John, thanks for making that so even I could understand it.
The picture's a little clearer, now

You all have a good Christmas.