Solitaire blue LED mod (photos added) - FIXED!!

[BugLightGeek]

alright. sounds sweet. Now, all I need are some more LED's to try it with.

What did you file the base of the LED off with? I have a Dremmel tool but was wondering if that would generate too much heat.

And, just to clarify, which leads are joined together and which leads do you plug in to the socket?

Glad to hear that the 2 LED's are brighter than just one. It wouldn't be worth doing if it weren't brighter, right?

Also, if you were to add a resistor, do you know how to figure out how much resistance is needed?

Hope you don't mind all my questions.

It's the only way I learn.

 

[Lantern Jack O.]

Questions r no problem. Keeps me on my toes.

To wire them in serial...

Connect L1- with L2+. L1+ goes into B+. L2- goes into B-.

To file the base, I used a miniature metal file. Probably an ordinary nail file would work fine though. Just be careful not to scratch up the lens portion of the LEDs. Dremel might be fine at low speed if you can figure out a way to firmly secure the LED.

Here's a link to a resistance calculator. Never really used it though. I just try out a few different resistor values until I like the current draw.

Update:
* I put some enamel nail polish on the joined leads where they go under the LEDs. This has completely eliminated the occasional grounding problem there.
* The LED's are still somewhat overdriven with a fresh battery. I'm going to try out some resistors next.

 

[Lantern Jack O.]

One Last Update...
I ended up making another one of the 2 LED Solitaire mods, this time using two white Nichia 5mm and and a 47 Ohm resistor in series. I used some low temp solder paste (Radio Shack) to join the LEDs in series this time. The solder paste worked very well, and the join has a much slimmer profile than the one where I just crimped the leads together.

I put the resistor inside the battery spacer, which was made of a bit of drilled out dowel rod. Just wound up the resistor leads on each end to make contacts on either side.

Beam shots (both at same distance, same camera settings, and on fresh batteries)...

2 LED Solitaire mod (White)

For comparison, here's an Arc AAA 3.1 White at same distance and same camera settings

 

[BugLightGeek]

Just wondering if you've done any 2-3 LED mods with a 2AA mini mag? From what I understand, 2 LED's would require 7.2v in series so you have to do them in parallel for 2 or 3 to even work given the voltage requirements.

So, how would I hook up 2 in parallel?
L1- to L2- and L1+ to L2+ then L2- and L2+ to the battery? Where would a resistor go?

 

[Lantern Jack O.]

Haven't done any 2 AA mods yet, though I've considered doing a 3 N-cell direct drive in a 2 AA body. Something along the lines of this.

There is an inherent problem when using only 2 AA cells for direct drive. The 2 AA batteries together only provide about 3V even when fresh. White Nichia's have a FV of about 3.6V, so that's not a very good match. Some of the other lower voltage LEDs should work fine though.

Assuming you're going to use white Nichia's, and that you're not planning to use a DC/DC boost, then you are correct about needing to drive the LED's in parallel. There's just not enough voltage to properly direct drive those LEDs in series on 2 or even 3 1.5V batteries.

You've got pretty much the right idea on how to hook them up in parallel. Just connect all the (-) together, and connect all the (+) together.

One slight modification though if you want to follow "best practice". It is recommended that each LED have it's own separate resistor. This is because the FV varies somewhat from one LED to the next, causing some to draw more current than others at a given voltage.

I personally would just try and do w/o resistors altogether at first to see if maybe I got lucky and used LED's that are closely enough matched. If one or more are drawing too much current, then it'd probably be best at that point to use resistors to balance out the current.

To do this, you'd wire one resistor in series with *each LED*. That's right, one resistor per LED. Use slightly higher resistance on the LED's that are consuming more current. Experiment with different values until they are all using about the same current, and are still within spec. I don't think it really matters whether the resistors go on the + side or the - side of the LED's (though I usually see them on the - side). The point of the resistors is to even out the current consumption so that each LED gets about the same (20 mA or so) current.

 

[BugLightGeek]

Jack,
I posted a question about what kind of 'stop' you used on your Mag Solitaire 2 LED mod here.

I can't make it out on the pict so I was curious. Does it allow the head to be tightened enough to turn the LED's off without having the plastic lens press down on the LED's?

 

[Lantern Jack O.]

Hey Chris,
I've tried two different kinds of stops. One was a tiny strip of plastic that I cut from a plastic pen cap. The cap just happened to have the 1/2" ID that matched the Solitaire's 1/2" OD. The appearance of that though, left something to be desired. The last time, I used a long narrow strip of aluminum that I cut from a softdrink can. (Careful! - very sharp edges.) If you put the inner, unprinted surface of the aluminum on the outside, it doesn't look half bad.

I'm not thrilled about either one of the above materials, and would love to hear suggestions/ideas. A very thin 1/2"D Al ring about 2mm tall would seem to be ideal. I just haven't thought of a ready source for those.

Anyway, I superglued the stop in place just above the shoulder where the lens/reflector normally stops.

The amount of travel the lens/reflector assembly is allowed is entirely up to how wide you make the strip. About the worst thing you can do with the stop is to make the strip too wide, not allowing enough travel for the switch to turn off - so be careful choosing the width.

Before trying to size the stop, make sure your switch assembly is firmly pressed together, because this can make a big difference on how tall the LEDs stand out. To do this, remove the LED (or bi-pin bulb), and press a pencil eraser into the back of the switch assembly in the battery compartment, and press firmly on the top of the bi-pin switch assembly. You'll probably feel a click as the two pieces come together nice and snug. After that, reassemble the whole thing and turn the head just a little past the "off" point. The distance between the head and the shoulder that normally stops the head indicates how wide your stop should be.

The last one I made was just shy of 2mm wide, and works perfectly. YMMV.

I can't really comment on whether your LED will hit the lens or not. Mine do because I've made it that way intentionally. There's no room for a reflector in the 2 LED mod. What I've found though, is that the stop keeps the pressure on the lens to a minimum while still allowing the light to be turned off very firmly so it doesn't come on by accident.

 

[BugLightGeek]

Doesn't this cause the LED(s) to press against the plastic lens? Doesn't that cause indentions in the lens?

So far, the best solution you've found is cut from a soft drink can, huh. hmmm...there's GOT to be a better solution to this.

 

[Slick]

I haven't had time to play ..er finish building my major mods lately, so I thought I give the Solitaire mod a go.

In my travels I had acquired the appropriate spring and a T1 white led. Using a T1 led isn't quite as bright as the T1 3/4's but all you have to do are cut the leads to the right length and plug it in...

Total time for the mod - about 3 minutes flat!

The T1 drops right in with no reflector drilling or "lens bashing". I like it although it can't quite keep up with my "NO-black-dot-no-mo" Infinity.

 

[hank]

T-1 LED and ....
--12v battery and spring?
--12v and resistor?
or what?

 

[Slick]

I just used a spring... (no resistor)

 

[Lantern Jack O.]

Doesn't this cause the LED(s) to press against the plastic lens?
The stop is just a protective measure to keep too much stress from being applied to the lens. Until I added a stop, I either had to overstress the lens, or risk having the light come on in my pocket.

Doesn't that cause indentions in the lens?
The lens is fine in mine. No permanent indentions. The stop works quite well if the instructions are followed. Done properly, you can tighten the head as hard as you want, and the pressure on the lens is still very minimal because the stop bears the the pressure, not the lens.

So far, the best solution you've found is cut from a soft drink can, huh. hmmm...there's GOT to be a better solution to this.
Yeah. The aluminum is nearly invisible if you're using it on a silver finish Solitaire, but it is kind of a pain cutting an aluminum strip of just the right size. I'd sure like to find a ready made metal or even a plastic ring that would just drop over the flashlight head. Any ideas? 1/2" ID, very thin, and 2mm tall would be about perfect.

---edit---
Just occurred to me that maybe a small slice of some 1/2" heat shrink tubing might do the trick. Probably wouldn't look half bad either.