MagLite 4D ROP possible?

[z_BBrolegend]

Hey guys,

I have a 4D Mag, that I want to upgrade with the ROP, (and a steel reflector and glass lens ;)

But I'm wondering if it's possible to run the ROP with the standard 4D cells? (and by possible I mean a reasonable brightness)

So, how many lumes will it put out with put out with 5~6 volts?

Do I need to modify it? and if so, in what way?



Thx in advance!!

 

[HotWire]

http://www.candlepowerforums.com/vb/showthread.php?89018-Building-a-ROP:devil:

 

[vinny]

I put my rop low bulb in my 4d maglite and it really wasnt that good, very dim and yellow, the high bulb was even worse, you could always use 6 x 1.2v sub c batteries in your 4d maglite.

 

[alpg88]

you need 7,2v min for rop to realy work, 2xli ion even better, i use 2x26650 in my rop high mod, it is almost as bright as mag85.
keep in mind there are different pelican bulbs, some made for nimh cells 7,2v-you don't want those, and there are bulbs for lead acid battery, they are 6v, those are the ones you want.

 

[KiwiMark]

But I'm wondering if it's possible to run the ROP with the standard 4D cells? (and by possible I mean a reasonable brightness)

I'll throw in the quick answer = no, it would be rubbish on 4 cells.

As vinny says you could go with 6 shorter cells, that would bring the voltage up high enough for the ROP bulbs to produce reasonable brightness.
You could also pick up a Mag2D and put a couple of Li-ion cells in there - that works really well.

 

[vinny]

I'll throw in the quick answer = no, it would be rubbish on 4 cells.

As vinny says you could go with 6 shorter cells, that would bring the voltage up high enough for the ROP bulbs to produce reasonable brightness.
You could also pick up a Mag2D and put a couple of Li-ion cells in there - that works really well.

When i set up my rop hi 2d i was using ultrafire 18650's, yeah it worked but its not safe in my and others opinions, if the cell's cant handle a 5 amp draw there is a serious risk of explosion inside the light! also because these lights are pretty water proof/airtight the gas has no where to vent so what you basically get is a pipe bomb in your hand, now obviously its only dangerous if the cells cant handle it, if for instance you were using aw, or imr cell's then it would be okay, if you know what your doing when it comes to li-ion then go for it, im not trying to put you off im just passing on the info that was passed to me when building my rop 2d.

I have used both 18650's and 6 x AA nimh and to my eyes there was no real difference between the two, but it is nice knowing i can run it for a long time on the AA's and not have to worry about over discharging my batteries and the possible side effects that can cause.

Just my 2p's worth by the way,

Vinny.

 

[KiwiMark]

When i set up my rop hi 2d i was using ultrafire 18650's, yeah it worked but its not safe in my and others opinions, if the cell's cant handle a 5 amp draw there is a serious risk of explosion inside the light!

Excellent point - never use cells that can't handle the load or are only barely coping with the load.

In my case I am using cells that are under 1C with the ROP Hi bulb - so no problems handling the current draw. In fact in a 2D there are many good options for suitable Li-ion batteries. For example, how about 26650 cells?

 

[srfreddy]

Excellent point - never use cells that can't handle the load or are only barely coping with the load.

In my case I am using cells that are under 1C with the ROP Hi bulb - so no problems handling the current draw. In fact in a 2D there are many good options for suitable Li-ion batteries. For example, how about 26650 cells?

Why would you use Li-ion? Li-mn has higher voltage at high current draw, more current delivery, higher nom voltage means the incans stay whiter.

 

[KiwiMark]

Why would you use Li-ion? Li-mn has higher voltage at high current draw, more current delivery, higher nom voltage means the incans stay whiter.

At under 1C my Li-ion cells are not dropping the voltage much - this isn't a high current draw for my 5,000mAh cells. My ROP Lo stays nice and white for 2+ hours of run time.

BTW:
When I say Li-ion I actually mean either Li-Co or Li-Mn - both are Li-ion.

 

[missionaryman]

Best ROP of the 8 or so I ever built was a 4D - use 1/2 D 4000mah NIMH cells, the barely feel the current and you get 1hr run time, I heat shrinked mine like a magcharger stick for easy charging and changing.
Here's the thread but I don't know where the pictures went sorry: http://www.candlepowerforums.com/vb/showthread.php?147960-4D-ROP-with-never-before-seen-battery-pack...

This ROP was sending so much current to the lamp that it melted the solder off the base after a few minutes and I had to re-solder with hi temp solder. From memory I was measuring about 4.5A at the tailcap

 

[fivemega]

Powering up a Hi 3854 bulb using 2S/2P 18650 is most efficient way.
Well more than an hour run time in 2.5D M*g, easy to carry, light weight, no double click, flat curve discharge and less frequent recharging.
Two parallel groups of two serial batteries share total required current so each protected 18650 provides about 2.2 Amp which is less than 1C. Therefore no stress on cells.

To use NiMH batteries 6S/2P AA set up also is the best known ROP Hi 3854 in 3D size.
Long run time, LSD batteries, flat curve discharge and possiblity to use with alkaline and ROP Lo