I've read through a bunch of the DIY threads but can't find the specific info I need. I have a P60 host that will fit 4 RCR123A cells or two 18650 cells. I'd like to mod it to be a real thrower. With four 123 cells I would need a drop-in that can take 18V. Those are available, but so far the brightest one I saw was 320 lumens (unless I missed some).
So... if I have to create what I need that's fine, I'm adept at soldering and making things fit, etc.
First off, which battery choice would you pick? I "think" 18650 cells can handle more amp draw if I am correct? But would the double voltage of the 123A cells have any benefit?
I'd like to see at least 900 lumens if that is possible. I know it's possible on one 18650 but is it on two? Is there a specific driver that can handle what I want to do?
So I could throw up my hands in defeat and say OMG I'm gonna kill myself if I try this. Or I could do the proper amount of research and come out on top with a really cool modded light. I'll take the latter. If it doesn't work I lost a few hours of time, if it does work, I'll have a cool light.
If I was going to go that route, I would build a vent or two into the body. Batteries venting inside a waterproof body are what seem to cause most of the more serious incidents.
And you asked for advice, you don't like mine, that's fine. I hate to see anyone lose a finger or an eye or worse for lack of information. In four hours, I haven't seen anyone else volunteering or recommending that you mod a multiple-Li-on light. Maybe there is a reason for that.
Just get IMRs if you are afraid. If you are still afraid get LiFePO4s. The real issue that i have experienced is the mosfets go poof due to heat, and after that = dead short. Protected LiCo is pretty safe, it is really totally safe if you use the branded Sanyo cells like XTAR, always do voltage measurements and ensure the matched cells stays matched. Invest in a hobby charger, do discharge tests so that they are really the same and stays matched.
Trust me, 1 x 18650 lights can still kill you with a faulty driver. It is not the number of cells, but YOU, the user.
You are trying to do mods, you need to be prepared to do all of the above. If you were a normal user, then perhaps yeah....stay with single protected cell lights. For the really layman users, stay with the NiMH lights like TK70.
The Lithium Manganese based cells are not only safer but are much better at supplying high current draw without voltage sag. The one downside is capacity, but the latest panasonic cells have come a long way in resolving that (LINK)
Note with the LiFePO4s, that your nominal voltage is ~3V and fully charged is ~3.7V versus 3.7V and 4.2V for LiCo and LiMn based cells.
That is correct Ford Prefect. And with multiple cells and a good driver, LiFePO4 is good to go in providing a good range for the voltage required. Yep I have seen that link, that Panasonic is absolutely crazy! I actually have a pair in transit from HKequipment.
Well that depends on how long it takes me to decide on what's the best path. Right now I would say XM-L or SSC P-7. But I'm open for suggestions.
And just so people know, I'm not trying to build the world's brightest flashlight or blow my fingers off. I just have this old host that isn't being used so I thought it would make a good mod candidate.
As oldbobk mentions if ultimate throw is what you really want as opposed to decent throw with a bigger beam then using an aspheric with a XR-E is the way to go.
If you want decent throw with a bigger beam you aren't going to get that from a P60 sized head (you would need XM-L in a larger diameter head).
An XR-E driven to 1A with a 28 mm aspheric will give you throw. Paint out the Cree Ring and the reflector and you will get a much cleaner beam as well. It takes 5 minutes or less to do this one.
If you want more throw you need a bigger aspheric/head. You get more bang for the buck with increasing head size than with driving the LED excessively hard. The relationship between increasing diameter to throw is linear. The relationship with increasing the brightness to throw is squared so twice the brightness only results in 1.4 (40%) more throw. Doubling the diameter would result in twice the throw.
The P60 lights are the Solarforce, Uniquefire, Trustfire, etc lights that all pretty much look like a Surefire 6P except that most of them take either (2) CR123's or (1) 18650.
I'm sure you know that so I may be missing that part of your question.
I can't see how any P60 compatible light can work without either the reflector or a spacer of the same size as the reflector since the pill is held in place only by the front lens pushing against the reflector which is against the pill.
However you can use the reflector as a spacer and not have it interfere with the aspheric just by painting the reflector black.
The one you are talking about, Bob is this. It takes P60 pills. The reflector is about the same diameter as a C8 but its about 6mm deeper, IIRC. Its a copy of the Dereelight DBS. See this thread.
I see what he was asking now. Using a P60 pill where you remove the reflector on the pill and use the reflector on the existing light.
Regarding this light posted to do you have it VfMaddict? It seems to imply it's a R2 in the name but I guess it's a Q5 (XR-E?) but on high it says it's driven at 2.8A? That can't be right so what's the deal?
Nope, gcbryan, I don't have that Trustfire but several around here do, as discussed in the thread I linked to (i.e. this one) I've been meaning to buy one for a while but the budget always get spent on one light or another. I'm sure I'll get one at some point though.
CPF is completely paranoid on lithium cells. Thousands of users (most of whom aren't even that conscientious), and the incidents in that forum are still from 2009/2010, with incidents resulting from obvious user errors.
Don't see them recommend against Surefires which are 2 cell only.
I don't think that TF-R2 takes a standard C8 size reflector. IIRC its deeper than a C8 and similar depth to an RQ Spear reflector or the genuine DBS light.