2D Mag goes 4*Seoul (w/ pics, now w/ beamshots)!

I just got finished a 2D mag mod with following specs:

- 2D to 8AA battery holder
- Battery tube inner diameter sanded 1mm larger (holy crap what a job! :green: ) to accept those damned oversized Energizer 2500 mAh Nimhs.
- Shark converter
- 3 stage switch: 50 / 250 / 1000 mA
- Runtimes 35 / 8 / 1,5 hours correspondingly
- UCL lense
- 4*Seoul P4 U bin leds
- 4*McR20s reflectors
- Works best with Nimhs, but alkalines can be used as well. With alks the runtime at high drops to 30 minutes but other runtimes remain the same.

In case of emergency 2 D cells can be used as well. Low and medium level will work ok then, but you will not get full brightness at high.

Here is general pic of the mod:



That is what the business end looks like:



Yet closer look on the business end. It was very hard to get the emitters centered because the reflector hole is much bigger than the led dome.



Here you can see the current setting 3 stage switch. I left the original switch as it was for turning the light on/off. Watching carefully you can see a reflection of me and my camera...



At high mode the light head gets quite warm, some 50C at room temperature. You can touch it but you don't want to hold it in your hand for a long time. This makes me think that 15W of heat is pretty much the upper limit that the Mag head can safely handle.

Thanks for looking!

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

Nice job!

What did you use for a heatsink/mount for the emitters?

Re: 2D Mag goes 4*Seoul (w/ pics)!

Thanks! I used Modamags PTS2 heatsink, see this thread: http://candlepowerforums.com/vb/showthread.php?p=1266271 . I cut it down so that there is perfectly flat surface where you can install the leds. You can see this flat aluminium surface if you look between the reflectors.

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

:goodjob: Nereus, as you have set the 3 stage switch with the shark? :thinking:

Re: 2D Mag goes 4*Seoul (w/ pics)!

I guess I need to read up on the Shark. I didn't realize it had multi levels.

Sometime this year, I'll be doing something similar but I'll probably do it in a 2C housing. 3 or 4 Crees. I deally, I'd like to be able to do about 20mA to each LED for low, 200 to each LED for medium and about 600 for high. The 1000ma would be cool for just generally being impressive, but I think at 600, it would put out adequate light and get that much more runtime.

I'd probably use 2x18650 cells.

My big question is, what is the spill beam like on the 50ma setting? Is it plenty for walking in rural/woody areas without attracting too much attention. My goal would be something about as bright as the SMJLED PR 'bulb'. I'd imagine 50ma to each SSC would be well beyond that though.

Re: 2D Mag goes 4*Seoul (w/ pics)!

I bet that thing is bright. I love those Seoul's. I very tempted to make a 2 C size mag with 3. Great job.
Norm

Re: 2D Mag goes 4*Seoul (w/ pics)!

ok:thinking:,how does the switch work?what kind of switch is it?how is it implemented?

greetings,alex

Re: 2D Mag goes 4*Seoul (w/ pics)!

boef800 said:

ok:thinking:,how does the switch work?what kind of switch is it?how is it implemented?

greetings,alex

Click to expand...

Here is a foto of the 3-stage switch:



Here is a foto of the (waterproof) rubber cover:



There is a tiny potentiometer on Shark with which you can adjust the current. It can be easily replaced with wire+resistors and with the switch you can choose which resistors are active, mimicking different positions of the current setting potentiometer. See this thread for good info on Shark: https://www.candlepowerforums.com/threads/105492 .

Thanks for positive feedback, guys!

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

cratz2 said:

...My big question is, what is the spill beam like on the 50ma setting? Is it plenty for walking in rural/woody areas without attracting too much attention. My goal would be something about as bright as the SMJLED PR 'bulb'. I'd imagine 50ma to each SSC would be well beyond that though.

Click to expand...

Originally I built this with 4*LuxIII u-bins and McR20 reflectors one year ago. At that time 50 mA was a very good low setting. You have it right: now with the Seouls the low mode is slightly too bright, some 20-30 mA might be ok. I was a bit lazy now and did not upgrade (downgrade?) the lowest current... I have built some mods with SMJLED PR bulb and I can assure you that 50 mA is way overkill if you are seeking for similar amount of lumens.

One very interesting feature of the mod is the fact that when using alkalines the light goes to direct drive mode at low. This happens because under light load the voltage of an alkaline battery is higher than that of nimh's. I measured some 80 mA input (and output) current at low with fresh alks. And dd mode is pretty efficient...

Let's see if I will be going to countryside next weekend. I could post some real world beamshots at different modes to give you an idea what the output looks like.

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

You know we all love those beamshots!

Re: 2D Mag goes 4*Seoul (w/ pics)!

Why dont use a dial type potential meter. variable resistance

Nereus said:

Here is a foto of the 3-stage switch:

Here is a foto of the (waterproof) rubber cover:

There is a tiny potentiometer on Shark with which you can adjust the current. It can be easily replaced with wire+resistors and with the switch you can choose which resistors are active, mimicking different positions of the current setting potentiometer. See this thread for good info on Shark: https://www.candlepowerforums.com/threads/105492 .

Thanks for positive feedback, guys!

-N

Click to expand...

Re: 2D Mag goes 4*Seoul (w/ pics)!

snipinglight said:

Why dont use a dial type potential meter. variable resistance

Click to expand...

That came to my mind 1 year ago when I started this project. I wanted to have 3 fixed levels instead of infinite amount of levels so I used a switch. Like that you know exactly at what mode you are running the light and most importantly you know what kind of runtime to expect. With infinite levels it is much harder to know that - in the worst case situation you run out of electricity because you had no idea how many amps the light was pulling out of the batteries.

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

Good job! :thumbsup:

I'm wondering how you could keep the reflectors centered. :thinking:

Re: 2D Mag goes 4*Seoul (w/ pics)!

Icarus said:

Good job! :thumbsup:

I'm wondering how you could keep the reflectors centered. :thinking:

Click to expand...

Thanks! I have a special trick up my sleeve to center the leds... :nana: I could post some pics on that part of the mod process too, so stay tuned for further info guys!

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

Icarus said:

Good job! :thumbsup:

I'm wondering how you could keep the reflectors centered. :thinking:

Click to expand...

Yes i'm curious about this i think you have used a plastic ring where it fit around the led and where the reflector sit.

Re: 2D Mag goes 4*Seoul (w/ pics)!

Nereus,

Nice job!

But I don't see how you can get 2 hours of runtime from 8AA Ni-MH @ 1000mA.

If 15W goes to the LEDs (which seems just a little over rated considering the Led's forward voltage, I would say it is more 14W), and assuming the circuit is 85% efficient, that means the circuit taxes 16,47W from the batts.

At this kind of current, an 8 AA ni-MH pack will give you at most 2500mAh if you choose Sanyo 2700. This is 24Wh.

If I do the maths correctly, you will only have around 87min. And that is with out of the charger batts...

If I change circuit efficiency to 90%, you should have 92mins. We are still half an hour from 2 hours.

How can you get 120 min at this power??? :huh2:

Re: 2D Mag goes 4*Seoul (w/ pics)!

Damn it, you have it correct! I must have confused this with some other mod... I will edit the original post - thanks for your comment!

-N

Re: 2D Mag goes 4*Seoul (w/ pics)!

:goodjob:

It's true it's easy to get confused with these numbers... I made myself a little spreadsheet with Excel to calculate current draw and autonomy from number of leds, current to the leds, Vf of the leds, circuit efficiency, number of batts, voltage and capacity...

Very usefull!

Re: 2D Mag goes 4*Seoul (w/ pics)!

It is time for a beamshot competition! Standard 2D Mag on the right, 2D Mag seoul on the left:



First one indoor beamshot. I guess that I do not need to tell you which one is the Mag 2D seoul @ high?



Mag 2D seoul @ high and std 2D Mag side by side:



Mag 2D seoul @ high, the distance to the shed is some 200 m (checked with a map):



A bit closer distance this time, Mag 2D Seoul @ high. Distance to the trees on the right and left is some 5m. Distance to the trees in the middle of the pic is some 30m.



The same view, Mag 2D Seoul @ mid:



The same view, Mag 2D Seoul @ low:



The last photo shows that there is usable side spill and throw (up to 30m) even at low - it should answer your question, Cratz2. Generally the Mag 2D seoul has "floodish throw" beam: generous side spill and good throw and the light is good at distances up to 250m, IMO. But if you want more throw you should use bigger reflectors.

-N

ok in your opinion, whats brighter? the quad u bin luxeons or the quad seouls?

im contemplating my quad u bin mag and dont know which way to go, cree or seoul