OT: flashlights again

Mar asked if I might enjoy Chinese tonight. That's femglish for "I don't feel like cooking". Roger that. We went to the pretty-good Chinese place, ordered some takeout. While they were getting that ready we went down a few doors to bum around in the Goodwill. I spied a hishlight, ohmygosh. I almost resisted it, but Mar said I

*must* buy that hishlight for $4.99. This is an instance of the orignal "hishlight" my Dad brought home from Camp Perry for me before he deployed to Guam in WWII. I was a very little boy, too little to say "flashlight" (hence the term hishlight) but apparently not too little to love it instantly and once clock a matron in the forehead with it who'd tried to relieve me of it as being too heavy for a tyke. MY hishlight -- bonk! I barely remember that event other than that I was being held aloft by someone else at the time , probably Ma. Ma laughed about that for the rest of her life whenever the subject of flashlights came up. It ain't a replica, it's the real thing: the L-shaped MX-991\U with O-ring seals. I'm quite sure it's not a Chinese knockoff because it says "made in USA" and the threads on it are inch (12 TPI) not metric. How could I not have a real "hishlight" at Donnie's house, 60+ years later? There is a threaded ring missing from the front. I can easly make a replacement, though it won't be olive-drab. There are some filters stored in the endcap: a faceted clear diffuser (flood), a white diffuser (tactical) and a bluish-purple filter (signalling?) The switch has a mid-position where a little adjacent pushbutton can be used for signalling in morse code. It works. There probably was also a red filter in there originally. The belt/webbing clip is not sprung and the metal slide-switch works fine. Both are brass, or maybe phos-bronze since they're springy. Some of the black is worn off of the metal. I don't think I'll try to restore that, just leave it as "experience". The rest of the light is in excellent condition. The reflector is metal. Other than Pelikan, what's the last flashlight you've seen with a metal (not metallized plastic) reflector? Maglite reflectors are metallized plastic. This flashlight model was in military use during WWII and 'Nam, presumably Korea as well. Don't know how long after that. It's probably not quite as robust as a Maglite, but it's not far behind it and it's a hell of a lot lighter in weight with batteries. It's flat base and L-shape enables it to stand on a flat surface and point at something you need to work on with both hands. There's a flip-out ring recessed in the base for hanging the light on a caribiner or whatever when the belt/webbing clip might not suffice.

Good functional design is almost timeless. A google search got zero hits for actual units or even knockoffs, but there are plenty of models and action figures that include a model MX-991\U as part of their kit. It is unremarkable as a source of illumination: it's a plain-vanilla

2D flashlight in that regard, not as bright as a Maglite 2D. As you might guess, I think I'd like to fix that.... I'd like to fit it with a Carley #1908 or #1937 deep paraboloid reflector and a 3-watt Luxeon. The reflector in it is in mint condition but a deeper short-focal-length paraboloid would work better with a Luxeon.

formatting link
(I recently learned about Carley from a poster on RCM. Thanks!) I think there's ample room for drive elex in the head. A pair of D cells will run a 3-watt Luxeon for quite a while. I tried a 3-watt Lux tonight in a slightly smaller reflector I had at hand (from a Pelikan flashlight), compared spots on the wall side by side with this light with new batteries. Very similar spot size, HUGE difference in whiteness and brightness. The Luxeon-ized MX-991\U would put a 2D Maglite to shame and would meet or beat 3D Maglites with krypton bulbs -- with less than half the weight. The elex will also keep it running bright throughout battery life, quite unlike any incandescant flashlight including Maglites. And, like most Luxeon lights, the spot will be absolutely free of mottling and filament image artifacts. The more I think about this the more eager I get to do it. Given my "hishlight" history, I gotta do it. I can just imagine Olga (Ma) and Big Don chuckling. I'll be on the lookout at "old stuff" stores, in case I see an original threaded nose ring, but I'll make one of black delryn for the interim. I suppose I could also make it of aluminum and anodize it OD... Fun, huh?

Reply to
Don Foreman
Loading thread data ...

When you get it up and running, post the project please

Ive got about 4-6 L head military flashlights and converting a few to LEDs would be cool

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

Reply to
Gunner

Don Foreman wrote: [MX-991/U]

I've bought maybe a dozen over the past couple years from E-bay at a few bucks each. Usually at any point in time there are several listed. (Some with ridiculously high starting bids but those'll never sell...)

But, unlike typical cheapie "straight" flashlights, the bulb will last much longer in transport. What kills the bulb in straight flashlights is the batteries putting direct pressure on the bottom of the bulb - drop it such that the weight of the batteries ends up on the bulb and the bulb's a goner. (Or the reflector is!) The right-angle in the MX-991 makes sure that doesn't happen.

I'd rather you keep it as it is, but since when do you ask me? :-).

Tim.

Reply to
Tim Shoppa

Yeah Don, fun! Thanks for some good reading and a glimpse back into flashlight history.

Reply to
Robert Swinney

We have a gag sign on our kitchen wall picked up at a souvenir shop on some trip we took. It reads:

KITCHEN CLOSED PROCEED TO NEAREST RESTAURANT.

We went to the pretty-good

I remember having a similar shaped one I got as Boy Scout gear in the late 1940s.

**********

Now, the unique flashlight in my toy box is a "Collins No Battery" one. Circa the late 20s or early 30s it's natural aluminum with the same size and shape as a regular 2-cell design, but in place of two D-cells there's two wide coil springs, which are mechanically coupled in series wouldja believe? a small PM rotor alternator driven by a step up clockwork train lights the bulb. You wind it by twisting the head relative to the body (Its ratchet clicks as though you were winding a clock.), and the slide switch (In the same location as on a "real" flashlight.) jams something into the gear train to "turn it off"

Jeeze, there are collectors of EVERYTHING. I just Googled my Collins, and here it is down near the bottom of this page on the right side:

formatting link
My favorite WWII military relic is an M1 entrenching tool. (One of those little folding blade "camping shovels".) I remember being on the street outside our family home on Lombard Street in San Francisco a couple of blocks from the Presidio (An Army base) circa 1945. A GI walking down the street stopped to talk to me and ended up taking the shovel off his backpack and showing it to me when I asked him about it. He ended up giving it to me. I don't remember if the said anything memorable during that presentation, though I could probably make up a few good epithets on my own, but that'd be cheating.

I still have thst shovel (It's stamped "Ames" on the blade.) and use it frequently for gardening. I'm sure they are a lot more common than Don's flashlight, as I picked up another one on ebay for around $15 to give to a son who was kidding me for treasuring that tool so much and always reminding him to take care of mine when he borrowed it.

Jeff

Reply to
Jeff Wisnia

OK. Don't hold yer breath, but I will get around to it sooner or later.

This conversion probably wouldn't be too pricey if several guys did it. The hooker with buying Luxeons, circuitboards and probably reflectors is minimum charges plus inflated shipping -- which can be minimized if spread around a little. Example: 3-watt Luxeons are $8.50 each. Elex parts would probably be $5 to $10. Circuit boards are about 60 cents per flashlight but there's about $50 of overhead per lot.

Barter works: for example, I might stuff a circuit board (surfacemount parts, need a microscope) in exchange for a genuine nose ring and red filter.

Reply to
Don Foreman

I said my Collins flashlight used two wide coil springs. I meant to say two wide *clock* springs.

Jeff

Reply to
Jeff Wisnia

Reply to
Robert Swinney

My 2 old standbys are a 3d Ray-O-Vac sportsman and an old 2d Ever ready magnetic mount. Both are old, but not old enough to have metal reflectors. The Ever Ready has plated brass ring holding the reflector/lens. Both are the old chrome body, and theSportsman has the off-flash-on slide switch (not lucas).

Reply to
nospam.clare.nce

You need GI parts? Let me check..hell I can probably send you an entire flashlight.

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

Reply to
Gunner Asch

Cool

Pending a look at how well the Carley reflector works, I'm moving toward a 1-watt Luxeon rather than a 3-watt for this light. 1-watt with a good reflector compares very favorably with a 2D Magite in brightness and is WAY brighter than the standard MX-991\U. It has more than half as much output as a 3-watt -- go figure, but that's what the specs say: 45 lumens vs 80 lumens. That's plenty of light, much better battery life (25-30 hours on 2 D cells at full brightness), no heatsinking problem, simpler elex.

Half output power produces considerably more than half perceptible brightness due to how our eyes work.

Most of the available 3-watt lights run on 6 volts -- typically two

123 lithium cells. I'm now seeing why: it has to do with the elex. They're good lights, but 123's are pricey and don't contain nearly as much energy as D cells.

The 3W would be a neat "showoff" light but the 1W is more practical.

Reply to
Don Foreman

If I remember my physics. It requires ten times as much light to look twice as bright. Karl

Reply to
Karl Vorwerk

It's logarithmic, but I haven't found a reference that says what base log it might be or what multiplier factor would be "right". I wonder how one can say with any certainty when something is "twice as bright".

Bell (Alexander Graham) reckoned that sound must increase 10X in power to sound twice as loud, hence the Bel -- a ratio of base 10 logs and the more commonly-used deciBel which is 1/10 of a Bel.

I can attest that a 3-watt Luxeon looks "noticably brighter" than a

1-watt, but it isn't twice as bright. Reflector size and shape are much more important in realizing a "good" flashlight. That's one reason Maglight 2D's are "good"; they have a fairly large reflector that is quite deep with short focal length, so more of the light is collimated and less is spilled. A 1-watt Luxeon in a 2D Maglite reflector makes a damned good flashlight!
Reply to
Don Foreman

I had a little LED flashlight that used 2 123 cells and I found that for about a buck more than one 123 cell I could buy a 6v battery that was made from 2 123 cells in a plastic case. This was easily split open and the individual cells separated and used in my flashlight.

I then saw an offering from a surplus place where I could get a whole box on the 123 cells for about a buck a piece so I got a bunch of them. This was a whole lot cheaper than buying the doubles and splitting them.

Reply to
Roger Shoaf

Inverse square law for light. Check out the hpyerphysics pages - E=I/r^2

Martin [ rusty in his Physics so I bought Hyperphysics web pages ] Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

D> >

Reply to
Martin H. Eastburn

That deals with distance, Martin. It has nothing to do with perceived brightness produced by two otherwise identical lights at same range but of different luminous output.

Measuring perception is "soft science". How can one know one light looks twice as bright as another rather than 1.8 times as bright? Maybe the human factors folks have devised a way to do that but I've not found it in the literature.

Reply to
Don Foreman

I'm certainly willing to be corrected. That was about 30 years ago. It would be an interesting experiment. Karl

Reply to
Karl Vorwerk

It would indeed. Any ideas on how to conduct such an experiment? The part that eludes me is how to say with any certainty that one light is twice as bright (or 50% brighter, or whatever) as another.

I found one reference from Lutron asserting that perceived brightness in % is equal to 100 * sqrt(% luminance / 100). This says that a source or spot with 50% luminance appears 70.7% as bright and 25% luminance appears 50% as bright.

From my own observations, this is at least plausible.

Things are further confused with LED vs incandescant because the LED light is much whiter so it looks much brighter. I would assert that if a flashlight *looks* bright, it *is* bright in terms of utility

-- being able to see stuff in an otherwise dark place.

Reply to
Don Foreman

Keywords:

I think one approach would be to do a side by side comparison of two sources. You could have a reference spot, and then an adjustable brightness test spot of the same size. Then folks could tweak things until they decided the test spot was twice (or 3 times) as bright as the reference. Then measure the actual illimination levels with a light meter. Still "soft science", but it's a place to start.

Doug White

Reply to
Doug White

Then use the oil spot test.

Power Per Unit Solid Angle

The power (flux) per unit solid angle (sometimes called pointance) is the nearest precise terminology to the common term intensity. It expresses the directionality of the radiated energy and is appropriate for the description of point sources. In the case of radiant power, it is expressed in watts per steradian. For visible light it is expressed in lumens per steradian = candela. Calculation to be added.

If the intensity ( I = dF/dw ) of a source is the same in all directions, the source is called isotropic. Otherwise, for a flat radiating surface, known as a lambertian, the intensity falls off as the cosine of the observation angle with respect to the surface normal.

Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

D> >

Reply to
Martin H. Eastburn

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.