How to make brightest 6D using 6 x NIMH

[uknewbie]

Hi all,

I have been searching for hours so have given up, please help.

I have a 6D Mag, Metal reflector, glass lens and have just got 6 x D cell NIMH, 10000 mAh LSD from Thomas Distributing, and am running a ROP Hi bulb.

Now this is a bright light, but didn't really blow me away like I had hoped :mecry:

Question is, how can I make this brighter?

Not overly concerned about runtimes, but want to use my 6 x D cells.

Was considering the bi-pin socket from Kai Domain, if so, which bulb would be brightest in this setup?

All advice much appreciated.

Craig.

 

[Benson]

Check LuxLuthor's graphs here. Assuming those cells will hold up 1.2V under load, you'll have 7.2V to play with, so look at the L vs. V curves for 6V bulbs. At 7.2V, the brightest is the 5761. (Note that those Lux measurements don't completely correspond to bulb lumens, because envelope and filament shape can change how much light goes which way, but they're a pretty good indicator of useful output in a typical reflector light.)

As you can see, you're a little close to the high end, but unless you do all the resistance mods, you probably won't have trouble with flashing the bulb.

 

[gswitter]

As you can see, you're a little close to the high end, but unless you do all the resistance mods, you probably won't have trouble with flashing the bulb.

I wouldn't count on that.

I've lost too many 5671's to 6x fresh NiMH cells, and the only resistance "fix" I've done is replacing the stock spring with the KD "lower resistance" dealy (and I've never verified if it actually reduces resistance).

I'd recommend the AW soft-start switch, or something similar.

 

[fivemega]

I wouldn't count on that.

I've lost too many 5671's to 6x fresh NiMH cells, and the only resistance "fix" I've done is replacing the stock spring with the KD "lower resistance" dealy (and I've never verified if it actually reduces resistance).

I'd recommend the AW soft-start switch, or something similar.

That's right.
6AA set up is much easier to 5761 than 6D. Your D cells won't sag enough to save the bulb.
Brightest set up which is still overdriving with direct drive 6 NiMH "D" cells is 3854 high bulb.

 

[uknewbie]

Thanks for the replies. The graph seems to show the 5761 going at closer to 8V, would this be worth risking with my 7.2V?

In any case, how much difference is there likely to be between the 5761 and my ROP Hi? Graph would indicate double the output?

Failing this, is there any way I could mix cells and increase voltage to allow the use of another bulb?

Other suggestions appreciated :twothumbs

Craig.

 

[gswitter]

Thanks for the replies. The graph seems to show the 5761 going at closer to 8V, would this be worth risking with my 7.2V?

Fully-charged, fresh off the charger, the voltage of an NiMH cell will be ~1.45V. The 5761 has no problem with 7.2V, but it can't handle the initial 8.7V. NiMH cells will sag to 1.2V, but how quick they do this depends on the capacity of the cells, and high capacity cells like D's won't sag quick enough keep the 5761 from blowing. A few solutions...

• Don't fully-charge the cells - can be a pain if you don't have a charger that provides the feature
• Add resistance - protects against initial instaflash, but also reduces output when the voltage of the battery settles
• Use a soft-start switch, NTC or something similar to limit the initial current until the voltage of the battery settles
• Use a voltage regulator - Alan B is making some, but I don't know if he's worked through the initial reservations list yet

In any case, how much difference is there likely to be between the 5761 and my ROP Hi? Graph would indicate double the output?

The difference in output appears significant to my eyes. I guess it depends on how much time or money you want to spend prepping your host for the 5761. If you're willing to spend the money, installing an AW soft-start switch is an easy solution (and completely reversible).

Failing this, is there any way I could mix cells and increase voltage to allow the use of another bulb?

With a host as big as a 6D, the possibilities are almost limitless.

 

[uknewbie]

Thanks again gswitter, makes a lot more sense now.

I appreciate the options are many for such a big host, but are there any that would facilitate using some or most of my d cells? Seems a waste otherwise as I can't really think of anything else I would use D cells for

Most of the adapters I have seen elsewhere on the forum all seem to relate to 2d or 3d etc, not sure about the 6D?

What I am really asking is what is the easiest way for me to get to 10 - 11V so I can run the 64430?

Cheers,
Craig.

 

[LumenHound]

Thanks for the replies. The graph seems to show the 5761 going at closer to 8V, would this be worth risking with my 7.2V?

In any case, how much difference is there likely to be between the 5761 and my ROP Hi? Graph would indicate double the output?

Failing this, is there any way I could mix cells and increase voltage to allow the use of another bulb?

Other suggestions appreciated :twothumbs

Craig.

Don't mix cells.
The 5761 looks about one good notch brighter than the ROP-HI but the difference may not be as much as your aiming for.

I wonder if anyone has tried overdriving the common 6 volt 55 watt H3 style bulb that comes in many inexpensive rechargeable spotlights up to 8.4 volts?

Have a look at one removed from it's base beside a 5761.

 

[donn_]

What I am really asking is what is the easiest way for me to get to 10 - 11V so I can run the 64430?

Craig...you can't get to 10-11V with 6 D-size NiMH cells.

If you switched to 1/2D cells, you could run 9 of them for 10.8V, with a spacer to fill in the empty part of the tube. This, of course, does not use the Ds you already own. If you have no other use for those Ds (you don't have enough lights!) perhaps you could sell them.

To maximize what you already have, either run the ROP or pop for a soft-start switch and run the 5761.

 

[uknewbie]

OK, I am with you now, thanks.

I do actually have a silver 3D with a q5 dropin and an aspheric lens which I could use the D cells in I guess.

However I will probably just make do with the ROP high bulb. As I said, this is a bright light, just not crazy take you by surprise bright. Although it does have some good runtime

Oh well onto the next one, I am looking to have something stupidly bright just for amusements sake. I don't actually need any more lights!

What is the brightest show off light that I could get without too much building/effort?

Thinking of venturing towards HID section...

 

[B.R.D.]

I wonder if anyone has tried overdriving the common 6 volt 55 watt H3 style bulb that comes in many inexpensive rechargeable spotlights up to 8.4 volts?

I tried a 75 watt with 11.1v lipo and it held up fine, but I don't know about the life of the bulb as I tried to push it on 12v:shakehead

 

[uknewbie]

OK back again with another question.

What would be the shopping list I would require to use my 6D as a host and run the 64430 at close on 11V?

There are obviously lots of battery options, which would be best for this voltage to maximise runtime in this host? The use of dummy cells always kinda annoys me so would prefer to avoid it.

Been searching for Kui sockets but dont know if something like this is still available?

Many thanks,
Craig.

 

[Benson]

OK back again with another question.

What would be the shopping list I would require to use my 6D as a host and run the 64430 at close on 11V?

• Batteries (see below)
• Kiu socket kit
• Some sort of switch upgrade
• Better reflector, lens, etc., if you like -- there's always ways to make a light more expensive!

The stock Mag switch is generally considered to be good up to about 5A. If you need a little more (as in your case), you can modify it a bit to reduce resistance (and thus heat generated in the switch), you can convert it to use a MOSFET to switch the bulb current, or you can rebuild it, typically with a rocker switch. You can also run it till it melts, then decide what to do with the new one -- and at only 8A, it may actually last quite a while.

You could also look at getting a regulated driver from AlanB -- costs a bit, but how can you put a price on continuous white light for the whole battery life? This would replace the Kiu socket kit.

There are obviously lots of battery options, which would be best for this voltage to maximise runtime in this host? The use of dummy cells always kinda annoys me so would prefer to avoid it.

Well, if you're direct driving, you need 9 cells NiMH, or 3 cells Li-ion (LiCo or LiMn chemistries, anyway). Don't know of any Li-ions that make that real easy while utilizing the whole tube, and of course you should read up on them and their dangers before you go that route anyway.

But the "obvious" solution is 9x 1/2D NiCd. Yeah, you'll need a 1/2D spacer, since 5x 1/2D = 3xD, but don't get hung up on that -- all the 3-stack configs wind up wasting more space around the edges than that spacer does at one end. This gives you 10.8V at 2.5Ah.

If you spring for a regulated driver, all you need is more than 11 V, so 10x 1/2D NiCD would work great (12V x 2.5Ah = 30Wh, and good for up to 500W or so into the right bulb). Alternatively (and this would be my preference) you could stuff the tube with 4x F (32900) LiFePO4, for 12.8V x 4.5Ah = ~60 Wh, and up to nearly 1kW. If you do this, you'll need a good balancing charger, or four single-cell chargers; while these won't explode like LiCo, you still risk wrecking your battery if you try to blindly series-charge it, so be sure you know what you're getting into...

Been searching for Kui sockets but dont know if something like this is still available?

Kiu, not Kui -- they're here.

 

[KiwiMark]

In any case, how much difference is there likely to be between the 5761 and my ROP Hi? Graph would indicate double the output?

The ROP Hi at 7.2V pulls 4.4A = 31.68W
The 5761 at 7.2V pulls 5.5A = 39.6W

If the 5761 is a bit more efficient then it could put out more light in relation to the wattage, but wont be drastically more. Also to look twice as bright would require about 4 times the output - the 5761 would have no chance of appearing 50% brighter than the ROP High.

 

[KiwiMark]

What would be the shopping list I would require to use my 6D as a host and run the 64430 at close on 11V?

My advice is to leave the 6d as a ROP High. Buy another Maglite and make a new hotwire with a nice bright bulb - the smaller you use the more impressive that it is so bright.

If you really want to be blown away then try this recipe:
Maglite 4D
5 x IMR 26500 cells
PVC tube from plumbing supplier with inside dia that the 26500 cells will fit inside and outside diameter that will fit inside Mag D.
Osram 64458 bulb
Aluminium reflector
Borofloat lens
AW soft start switch

This will blow you away for brightness and at close range can set paper on fire. I have not yet blown a bulb on mine, even on fresh batteries hot off the charger. This will have over twice as much Lux at 1 metre as the 64430 according to Lux Luthor's tests.

Note:
Don't shine this on a white wall at close range - it is painful on the eyes and you will be seeing afterglow for a lot of minutes.
Don't expect the 2 hour runtime that your 6D has - this is a ten minute deal at most.

 

[^^Nova^^]

The ROP Hi at 7.2V pulls 4.4A = 31.68W
The 5761 at 7.2V pulls 5.5A = 39.6W

If the 5761 is a bit more efficient then it could put out more light in relation to the wattage, but wont be drastically more. Also to look twice as bright would require about 4 times the output - the 5761 would have no chance of appearing 50% brighter than the ROP High.

I have both, the 5761 is visibly much brighter than the ROP-hi, but no way is it twice as bright. I would think you would need to go 4x the power to have the light seen twice as bright.

Cheers,
Nova

 

[uknewbie]

Thanks for all your replies guys, I do appreciate it.

KiwiMark, your idea of leaving as is and trying your 4D recipe seems very appealing.

The 6D despite it stupid size has very usable runtimes with what is still a very bright torch.

I of course do not "need" any more. I have a silver 3D with a Q5 dropin and aspheric lens and glass breaker, TK11 R2, Lummi Raw NS ordered awaiting delivery and of course the 6D ROP high.

Still, going to go down that 4D route you suggested, sounds like fun...:twothumbs

What charger should I best use for those cells would you suggest?

Also, where else is there to buy a high quality reflector, I suspect the ones I have from KaiDomain are not very good?

Soft start I require this one? http://www.lighthound.com/AW-Mag-D-...ti-Brightness-for-D-Cell-Maglight_p_2921.html

 

[KiwiMark]

The 6D despite it stupid size has very usable runtimes with what is still a very bright torch.

Yeah, it would be a shame to convert that to something less practical.

I of course do not "need" any more. I have a silver 3D with a Q5 dropin and aspheric lens and glass breaker, TK11 R2, Lummi Raw NS ordered awaiting delivery and of course the 6D ROP high.

That is not many - you could do with many more lights than that.

Still, going to go down that 4D route you suggested, sounds like fun...:twothumbs

VERY FUN!

What charger should I best use for those cells would you suggest?

Also, where else is there to buy a high quality reflector, I suspect the ones I have from KaiDomain are not very good?

Soft start I require this one? http://www.lighthound.com/AW-Mag-D-...ti-Brightness-for-D-Cell-Maglight_p_2921.html

[/QUOTE]

I like this charger:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7523
Or this one would work fine for a cheaper option:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7028
You would need a Computer PSU or other 12V DC source. The alligator clips will stick to the batteries with the use of magnets and you can string all 5 batteries together with magnets as well.

That would be the right soft-start switch.

There are a few options for reflectors like the 4th & 5th item on this page:
http://theledguy.chainreactionweb.com/index.php?cPath=48_56_73
I went with 0.500" opening.

 

[Swedpat]

Nice thread. I asked practically the same question in THIS thread. Some day I will make use of the beast 6D.

Regards, Patric

 

[uknewbie]

Hi Patric, yeah I did find your thread before in my hours of searching.

Doubt you would be disappointed with the ROP high if you were used to the led dropin in your 6D, like I say, it is a very bright torch, and still runs for hours. Plus if you already have the 6D and nimh batteries would be easy to do at little cost.

Incidentally, I dropped mine head over tail all the way down my stairs and it worked fine afterwards

Good thread because of lots of great replies, super fast too :thumbsup:

Craig.

P.S - I already have a nice blue 4D picked out for the suggestion above!