increasing amps

[rebelbayou]

Hi Everyone,

I have a simple question. I have searched the forums and archives and read until I'm blue in the face, but I have yet to find the answer to what is probably a newb question that's been asked a 1000 times. How can I increase the amps in a modded maglite? The answer would be nice, but if someone could point me to a simple, detailed link that answers this question, I would be much appreciative. I have a couple of modded maglites with 18650s' and have no problem with them. Now I have a 3D with 6 AA nimh that is showing 8.4 volts at the bulb holder, but it is no where near as bright as my 2D with 2 18650s'. The bulbs that I have tried are all Mag 4,5,6 cell Krypton and Xenon. I even put 9 AAA batteries in it and it has 11.5 volts at bulb holder and it still is not very bright. Funny thing is, it hasn't blown any bulbs. I'm not quite sure how to check the amps it's pulling with these battery holders, but I'm thinking my lack of brightness has something to do with amps or resistance. My favorite little 2C with 2 18650s' and a Mag 5 cell is my brightest incandescent and it only pulls .90 amps. Can anyone point me to some links or shed some light on this subject? Thank you all for your time and patience.

Rebel

 

[alpg88]

there are ways to decrease resistance in mags, but with 1-2 or so amps of draw you don't need to. resistance of stock mag is not an issue at those amps.
you can't really increase amps above what batteries can supply.
what holder do you use with 6AA? it may be the weak link,

 

[KiwiMark]

How can I increase the amps in a modded maglite?

Lower the resistance! Easiest way is to change the bulb - try a 3854-L - it should run well from 2 Li-ion cells.

 

[rebelbayou]

They are cheap 2-AA holders from RatShak. Everyone in CPFMP was sold out and I bought 4 or 5 of these cheap ones for a trial run as they were only .99 a piece. So, how are people pulling 4-5 amps from 2 18650s' in a few mods that I have read about on here? I have a bunch of good 18650 unprotected batteries that are just sitting around and I wanted to try to put them to use with a couple of spare Mag 3Ds' that I have laying around. I can't seem to get a grasp on volts, amps, resistance, etc. but it seems like every bright hot wire or incandescent is pulling a lot of amps and I was thinking that I just needed to increase the amps and I don't know how to do that. Please enlighten me and thanks for the reply.

Rebel

p.s. I also have a couple of the Pelican ROP bulbs on order but they haven't gotten here yet.

 

[KiwiMark]

So, how are people pulling 4-5 amps from 2 18650s' in a few mods that I have read about on here?

I'm not too sure why it would be hard - for ~4.4 amps I put 2 x 18650 cells into a Maglite 2D, the ROP High bulb (3854-H) an aluminium reflector (cause the plastic one's gonna melt) and a glass lens (also solves melting). I click the switch and ~4.4A flows. This is around 2C (C = capacity of the cell) which means you'll only get around 1/2 hour of run time - but it is a hell of a good amount of light (over 1000 Lumen). I haven't done any resistance mods, just the batteries & bulb change is enough to achieve the results I want. Seriously this is easy to do with no real work involved at all - stock switch, stock body, stock tailcap with stock spring (or shorter spring if using protected cells that a too long).

I wanted longer run time so I got bigger, higher capacity Li-ion cells, but still I use 2 Li-ion cells & the 3854-H bulb as my only mods for more power + Al reflector and glass lens as my only mods for heat handling. This is really simple to do and gives excellent results! For more throw my favourite mod is to use the fivemega 2" deep reflector, better beam shape as well!

I have 3 of the 2D ROP lights - 3854-L w/deep reflector, 3854-H w/deep reflector & 3853-H w/bi-focal reflector. I just love the ROP lights! I also have a 3854-H in my Mag 6D for a total of 4 ROPs. I also have 4 hotwire Mags, but they have the stock mag switches removed and replaced with AW soft start switches in 2 of them and Alan B programmable regulated drivers in the other 2 - much more expensive and more work. The ROP Mags are cheap & easy, but really good with great output and a good white beam (I used to find the stock bulb in stock Mag too sickly yellow).

 

[rebelbayou]

Hi KiwiMark,

Thanks for the great reply regarding the ROPs'. Please correct me if I'm wrong, but as I understand it, you are saying that you have 2 18650s' in a 2D mag and it's pulling 4.4 amps with a 3854-H bulb? Does the bulb really make that much difference regarding amps? As I stated in my first post, I have 2 18650s' in a 2C with an aluminum reflector, glass lenses, stock switch, and a Mag 5-cell xenon bulb with no resistance mods and it pulls .91 amps. So if I put a 3854-H bulb in it, it should pull around 4 amps or so? Sounds too easy. Btw, I have ROP bulbs ordered and are anxiously awaiting their arrival. If the bulbs are the only difference, then I'm in good shape as I already have a spare aluminum reflector, a few boro-float lenses, and quite a few unprotected 18650s'.

 

[alpg88]

As I stated in my first post, I have 2 18650s' in a 2C with an aluminum reflector, glass lenses, stock switch, .

that is a waste for 5 cell bulb, but a perfect set up for rop high.

 

[rebelbayou]

Well, they just happened to come in already but the bulbs haven't gotten here yet. The 5-cell bulb was already on hand and it gives the best hot spot of any other bulb that I have without blowing. Now, I'm really anxiously awaiting for the bulbs to arrive. I'm not really sure what the difference is exactly between 3853 and 3854 but I ordered 1 package of the Pelican 3853??:thinking:

 

[KiwiMark]

Hi KiwiMark,

Thanks for the great reply regarding the ROPs'. Please correct me if I'm wrong, but as I understand it, you are saying that you have 2 18650s' in a 2D mag and it's pulling 4.4 amps with a 3854-H bulb? Does the bulb really make that much difference regarding amps? As I stated in my first post, I have 2 18650s' in a 2C with an aluminum reflector, glass lenses, stock switch, and a Mag 5-cell xenon bulb with no resistance mods and it pulls .91 amps. So if I put a 3854-H bulb in it, it should pull around 4 amps or so? Sounds too easy. Btw, I have ROP bulbs ordered and are anxiously awaiting their arrival. If the bulbs are the only difference, then I'm in good shape as I already have a spare aluminum reflector, a few boro-float lenses, and quite a few unprotected 18650s'.

You've got the setup pretty well sussed and yes, change bulb and viola!

I'm not really sure what the difference is exactly between 3853 and 3854 but I ordered 1 package of the Pelican 3853??:thinking:

3853-H = about 3.5A
The bulb is less overdriven so you will probably get more hours of use before it dies. At 3.5A you'll get a bit longer run-time too. Not as bright as the 3854-H but brighter than the 3854-L.
The 3853-L isn't all that great, pretty much my least favourite bulb of the four.

My opinion of the bulbs:
3854-L - Fantastic bulb, decent run-time, great output. Handles 8.4V easily.
3854-H - WOW!, Fantastic output, BUT - close to on 2 fresh Li-ion cells (Lux's test show 8.5V=). I still love this bulb for the output, but I am scared to do any mods to lower resistance on my Mag2D using this bulb.
3853-L - Meh! Lux's test show at 8V though I've not blown one on 2 fresh batteries yet.
3853-H - Great output and tolerates the voltage from 2 fresh Li-ion cells much easier than the 3854-H. A good safer option with plenty of light output.

You already have the right setup so you can try out the 3854 set just by ordering it. The ROP mods are so easy it's ridiculous. I think I have 3 sets of the 3853 bulbs and 3 sets of the 3854 bulbs, but I have yet to blow my first one. 2 x Li-ion + ROP bulb = :twothumbs

When I go camping I usually take at least one of my ROP lights. The output is great and really lights up whatever I want really well. The run-time is a little short, but I take other lights with longer run-times and spare batteries - so no problems there.

During a power outage an LED light on medium can easily light up a room by shining the beam on the ceiling. But if you need more light for a few minutes to do something then try the ceiling bounce from a ROP light - talk about good illumination!

 

[Inliner]

Does the bulb really make that much difference regarding amps?

Yes. It makes ALL the difference. :thumbsup:

 

[alpg88]

yea 3854h is an awsome bulb, i run it of 6x4\5 sub c, no worries of
compared to 5 cell bulb, night and day.

 

[rebelbayou]

Thank you for the detailed, informative, and simple to understand explanation of the ROP bulbs! You've answered all my questions regarding amps and bulbs. I never would have thought that just changing a bulb can make that much difference in amps. My 3853 bulbs should arrive tomorrow. I can hardly wait. In fact, I think I'll order a package of the 3854 bulbs from Lighthound right now, as I am only 1 day shipping away from them. Looks like it might be a "light" party around here Saturday night. :twothumbs Once again, thank you all for answering my questions!!!lovecpf

 

[Justin Case]

I never would have thought that just changing a bulb can make that much difference in amps.

Ever notice 25W, 40W, 60W, 100W, and higher light bulbs in the hardware store?

 

[KiwiMark]

I can hardly wait. In fact, I think I'll order a package of the 3854 bulbs from Lighthound right now, as I am only 1 day shipping away from them.

Be careful - it wasn't long after getting my first ROP working that I had 5 separate Maglites using ROP bulbs - 6D 3854-H, 2D 3854-h, 2D 3854-L, 2D 3853-H & 2D 3853-L. Since then I have made one of my 2D lights into a hotwire with an AW soft start switch and I don't use a 3853-L any more because that was my least favourite. But I did buy a couple of fivemega deep reflectors and a couple of bi-focal reflectors to use instead of the KD Aluminium reflectors - so I have spent plenty.

Them ROPs are mighty addictive! They are also great lights - I consider my 3854-L to be a fantastic utility light with a decent run-time and really nice light output. I like using the ROPs around the house and taking them camping, if they would fit easily in a pocket then I would EDC one as well.

I :bow: ROPs

 

[rebelbayou]

Holy WOW! You guys were right about the ROP bulbs. Unfrickinbelievable! Love the 3854-L on 2 18650s'. Very bright and good run time. In my 2D, it pulls about 1.90 amps with the 2 18650s' showing 7.90 something volts. I put the 3854-H in my 2C running 2 18650s' for about 30 seconds and it scared me it was so bright. I shut it off because I'm afraid of blowing the bulb. I've read a lot of posts recently about members insta-flashing the H bulbs. I know Lux's test show at 8.5 volts and my volts are 7.97 at the bulb holder with no load. What do you think? Am I close to flashing the bulb? Should I let the batteries run down a little bit with the low bulb first? No resistance mods except for tail spring. I also have 4 18650s' that I just extracted from a laptop battery that say MOLI IMR-18650E that are resting at 4.15 volts each. Would these be better for the ROPs' or would it be too much? Thank you.

Rebel

 

[KiwiMark]

I use a 3854-H on 2 Li-ion cells all the time, really bright but bulb not blown yet. Sure it's a risk, but you can always throw the 3854-L bulb in there if the -H bulb blows. The 3854-H bulb has a shorter run time and probably wont run for as many hours before it blows, but what a great output! :twothumbs

 

[jasonck08]

Hello rebelayou.

You shouldn't need to worry about flashing that bulb with 2x18650's. If the resting voltage is 7.97, the voltage under about 2A load will be probably right around 7-7.4v depending on the resistance of the cell itself.

 

[rebelbayou]

Thanks for the advice. I have turned it on and off 3 or 4 times today and let it shine for 1-2 minutes with no problems. Comes on with 1 click just fine. I can't say enough about the brightness. I always wondered what 1000 lumens looked like. Lux's graph for this bulb shows predicted lumens at 7.7 volts to be a little over 1200. I know there are a lot of variables involved so I'm just referring to it in a generic sense. It may not be 1000 lumens, but if it isn't, I would bet it can't be too far under that. Bright enough for me anyway, and I have yet to show it to anyone who's jaw didn't hit the floor. :wow:

Still not sure about the IMR Moli 18650s' so off to the archives to do more searching and reading. Thanks again!