2x18350 & 2x18500 FM1794

ma tumba

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I keep playing with this flashlight. Now I put on an SF FM34 beam shaper, intended for 6P and such. This diffuser fits great and while the overal profile of the light is now far for being slim, I get something very special optically, in return.

When an SF beam shaper (either an FM34 or F04) is put on a normal throwy light, the output becomes much smoother but it is still pretty tight, similar to that produced by TIR optics, or triples. But when I defocus this FM light, with the FM34 on, it starts producing a perfect smooth wall of light.

So with the FM34 on, I am getting from TIR-like to wall of light, and when I open the lid of the FM34, I am getting tight throwy spot to wider spot, just by turning the head. VERY versatile combo indeed.

And btw, with an FM34 on, the 2x18500 version feels better in my hand than the 2x18350.
 
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Conte

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OK, now I get this. But I also found here a notion that AW sofstarts introduce some voltage drop. Does anyone have an idea, what kind of drop it is?

I measured it once, but I don't recall the number. Somewhere between 0.4 to 0.6 v, off the top of my head. Probably less in reality as I did the test using small guage wires.

I do believe it's a side effect of the circuit being powered off of the tail without access to battery positive.
 

Conte

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I keep playing with this flashlight. Now I put on an SF FM34 beam shaper, intended for 6P and such. This diffuser fits great and while the overal profile of the light is now far for being slim, I get something very special optically, in return.

When an SF beam shaper (either an FM34 or F04) is put on a normal throwy light, the output becomes much smoother but it is still pretty tight, similar to that produced by TIR optics, or triples. But when I defocus this FM light, with the FM34 on, it starts producing a perfect smooth wall of light.

So with the FM34 on, I am getting from TIR-like to wall of light, and when I open the lid of the FM34, I am getting tight throwy spot to wider spot, just by turning the head. VERY versatile combo indeed.

And btw, with an FM34 on, the 2x18500 version feels better in my hand than the 2x18350.

Pics or it didn't happen :p
 

ma tumba

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Now I got myself a few of these bulbs MAGLITE LMXA501 Replacement Lamp for 5-C Cell/D-Cell Flashlight (Mag-num Star Xenon), which have exactly the same footprint as 1499 originally installed in the light.

I think these are a better choice, as they provide whiter beam than a 1499, at all 3 levels of the AW softstart that I use, plus they are less power hungry and therefore more adequate for the smallish capacity of 2x18350. Also they are really cheap, I bough them at $2.77 shipped on amazon.

There are also 3-cell versions, LMSA301, that may work well with a single 18650. Although being not that bright and white as 2x18350 with 5-D, this configuration would provide way more runtime.
 

ShineOnYouCrazyDiamond

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Thanks for that info. It looks like the filament has a very small coil which is great for focusing.

Any way you can do a tailcap current measurement with this bulb to get an idea of the overall current/wattage it is drawing compared with a 1499?
 

ma tumba

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Thanks for that info. It looks like the filament has a very small coil which is great for focusing.

Any way you can do a tailcap current measurement with this bulb to get an idea of the overall current/wattage it is drawing compared with a 1499?

Actually, a 1499 focuses notably tighter, but it is not a big deal for me as opposed to the ability to UNfocus. Re the current measurement, I have a cheap multimeter which I think is capable just of sub-amper loads.
 

mjgsxr

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This is my favorite creation of yours yet. Any incan fan needs to get one before its to late. Very cheap light with your own tail cap. Another order

#08 Black 2x18350 FM1794 $57
#04 Grey 2x18500 FM1794 No tail cap $34
POST $24
TOTAL $115
:paypal:
 

ma tumba

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FM, is there a chance that the 2x18500 body would accept three flat top 18350? In my 2x18350, two flat top 18350s leave quite a bit of free space.

Just wanted to try the 11v axial bulb, btw do you have more of them at hand?
 

ma tumba

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Thanks!

My bored-out Surefire 9P fits 3x 18350 button top, so I'm sure 3x 18350 flat top would fit in FM's.

EDIT: what bothers me is that 9P is a 3x16350 light by design, while 2x18500 light may be shorter than that
 
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naked2

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9P is actually 3x CR123A, which are shorter than protected 16340/RCR123As. I have an FM bi-pin socket/reflector module which has a super stiff/long (+) spring. That coupled with a McClicky tail-switch (also super stiff spring), and 3x 18350 button top (IMR, no PCB) still fit fine.
 

ma tumba

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Your question was answered on post #2 few years ago.

They are available in custom bulb thread.

Shame on me, it was my own question back then!

FM, you write that prices include one 1794 installed, what would be the price of a 2x18500 light (no tail cap) with the axial bulb installed instead of a 1794?
 

ma tumba

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PP SENT

#03 Black 2x18500 FM1794 no tail $34
1794 replaced by axial G2 $2
intl shipment $12
TOTAL $48

NOTE: please don't forget to replace the 1794 by the 11V axial G2
and please provide the invoice/declaration number(s)
 

ma tumba

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Thanks for that info. It looks like the filament has a very small coil which is great for focusing.

Any way you can do a tailcap current measurement with this bulb to get an idea of the overall current/wattage it is drawing compared with a 1499?

Kind of answering this question. I now settled on the 3D Mag Magnum II bulb driven by single 18650 battery. I measure 0.90 amps at 4.1V.

With the 3-stage aw tail cap some phaseburn's diffusing film attached to the lens, this is my all time favorite night time light. I am so happy I finally got an incand light that is just perfect for night time indoor use.

Looking forward to getting the 2x18500 version of this light in a week or so. That one is going to be tried as an outdoor light, with either 5D Magnum II bulb (have tried this one with 2x18350 but it was too bright for night time, indoors) as well as with a cl1499 and a 3x18350 11V axial.
 
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