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LED Flashlights – General Info
101

I’m new to flashlight building/modding. As in brand new. I’m decent with a soldering iron but have limited experience with emitters/drivers/heat dissipation etc. I saw this thread and thought “man this would be a really cool project for the Boy Scouts”. I’m a Scoutmaster. Our troop camps once a month and the boys mainly have those crappy LEDs from harbor freight. Never know when they will just stop working. Plus a project like this would go a long ways towards them getting their electronics merit badge.

My question to you all is, is this a project 13-year-olds could handle with some “significant” adult supervision? How time consuming would it be? I appreciate your input. I’m totally new to the community and I hope I’m not hijacking the thread or anything. If that’s the case let me know.

Also, 18sixfifty, would you be comfortable receiving a fairly large order (enough for 10-12 flashlights) via paypal from a totally new member? If not I understand.

102

That actually sounds like a really cool idea. I would have had a blast making a flashlight back when I was in scouts! My main concern would be having 13 yr olds using a soldering iron that could be very dangerous even with heavy supervision. The first and second time I used mine I burnt a knuckle, but it could have been much worse.

Time consumption I would put at ~1 hour instruction, teaching, construction.

Checked on the host, this one looks to be fully assembled except the pill assembly, which is just a really simple 2 solder joints on the emitter and it’s done.

103

There's a few things about flashlight modding that make it tricky for adolescents.

First, usually things almost never fit right in, usually if you are not aware of that, the reflector may short led wires, possibly blowing up the driver, so solder blobs must be flat and on the outside of the solder pad, during assembly the dome can be knocked off, the soldering of the led wires to the driver is a quite precise piece of work, fixing the driver to the pill can be a pain. I work with adolescents and there are not many that have the precision and reflection on their own handling to do a succesful flashlight mod, even a relatively basic one like this.

Second, many adolescents are not able to be responsable enough to take care of li-ion cells. They will follow the guidelines as long as they are supervised, but become careless over time (ok, adults are that way too, but adolescent are far more careless, it is build in to act irresponsably, and that is important for their developement).

So when supervised with care, everthing is possible, but I do not think it will be easy.

104

Hey extdrive (welcome to BLF, by the way), if you decide not to go for a DIY-project with the children, there is a nice group buy going on at the moment of a very nice flashlight (but perhaps a bit expensive) that runs on ordinary rechargable AA batteries, the Starry Light flashlight, perhaps an idea too? :

105

Or a AA P60 and use a drop in? Not so much an electronic project though, more a of useful Lego type project. Id also add kids are notorious for shinning lights in faces. A dedicated thrower might not be a great idea.

Starry Light gets hot after ?15? minutes. I recall reading in the thread up to 85c. Too hot to touch.

106

Not a problem taking paypal at all.

I think it’s a great idea and this is a fairly simple mod. I wouldn’t have kids do the de-doming part. It’s too easy to bump the little wires and kill them. But the rest of it should be easy enough as long as you know how to do it first. This is actually not hard mod at all and I am more than willing to answer any and all questions. My advice would be for you to build one first with my help and that way you will know how to help them. Plus you could then explain about resistance and amps and volts. You could also learn the various components on the driver before giving your class to the kids. That way you will all be learning something.

It sounds like a really fun project to me and a very useful one. What kid doesn’t like getting a cool flashlight?

107

Is there an electronics merit badge. If so then this might be a good idea if a AA or AAA host were chosen. I wouldn’t start a bunch of kids out on lithiums. Especially knowing the batch of retrogrades I scouted with. If they get hooked you can tell them where to find us.

108

Ah I overlooked the lithium factor.

They would be looking at ~$20-30 in a good, reliable battery/charger/DMM on top of the $13 cost of the flashlight kit, and it takes more diligence than most teenagers would afford in caring for Li-ion batteries. It’s also coming from china so it could be 4+ weeks to delivery.

18650 is probably not ideal in this case.

I think teen-me would have had a blast taking on the responsibility, but I was a peculiar kid. :stuck_out_tongue:

109

Yeah that would make a AA light better for this kind of thing.

110

Wow, great response from this community. Thank you.

My gut instinct is to give it a go. I know the boys would really like a thrower like this. Super annoying when they shine it in my face at camp, but it sounds like it would be the type of flashlight that gets them excited to learn and try things out. Also there is a “cool” factor in using a Li-Ion. Just isn’t as sexy to make a AA or AAA flashlight. :stuck_out_tongue:

That said, thank you for adding reason to my overzealous personality. The “cool” factor is probably outweighed by the “oh crap” factor of explaining to a parent why their son has permanent burn marks from charging a battery. I think I will go with the combined experience/knowledge of the community over my gut instinct and look for a different project for them.

Me on the other hand…Well, shoot I was never that pretty anyway. Just because its not a good idea for the scouts doesn’t mean I have to miss out on the fun :wink:

Seriously, thanks again for all the advice.

111

I wouldnt drop the idea altogether. A AA or AAA light can be pretty kick arse. The beauty being able to surprise people with its punch for size. there must be a AA AAA that could make a good project build like this C10.

112

3x AA/AAA host kit should be around the same price maybe a bit more since it wouldn’t be in a group buy.

With the right host the same 105c driver could be used without size issues, and then the emitter choice is wide open.

Perhaps a new thread to generate ideas?

113

One way or another, the 3/4 x AA side-by-side form factor only comes in dirt cheap or pretty expensive lights. Perhaps making a half decent battery carrier cheap is too much of a challenge? I would be all over a budget host with a better-than-crap 4xAA series battery carrier and a good 17mm driver pill.

114

At that age, I was careful, meticulous, and precise. Not very patient though. And I would have absolutely loved a good flashlight. I would even go out sometimes carrying a spare car battery hooked up to a car headlight, though I could barely manage the weight. A light like this C10 would probably have been my most-treasured toy.

But I was a bit odd.

115

Convoy C8, add 2 of FastTech's extension tubes and run it on 4AA's. Later on they can always use Li-ion by just removing the extensions. They'll have a very versatile light that can use Li-ion, NiMH or even alkalines in a pinch.

116

AA or AAA lights would probably work. I really think the scouts would get a kick out of it making lights. I’m going to continue to lurk and learn a bit from the community and then I think I will follow your advice and start an new thread asking for ideas. Not sure I’m familiar enough with all this yet to even articulate my questions. :stuck_out_tongue: Thanks again everyone for the ideas.

117

I just got in a C10 host from Fasttech, I ordered it before it was decided that this group buy was going to be this C10 host. Perhaps it is nice to read some observations on it (I think it is safe to assume that this is the same light that is going to be delivered in the group buy):

reflector compared to a C8 reflector (Convoy C8 host), C10 on the right, with the big hole I guess you could squeeze in a MT-G2:

The pill is the 'standard' C8 pill, in fact the exact pill that is in the Fasttech Ultrafire C8 host, giving space to a 19mm board (why not 20???). So a 20 mm board shaved off a little should work, but I guess it is intended for a 16mm board, automatically centered in the reflector by the plastic spacer that comes with the pill, if an xml-led is used. It also means that some other C8 pills fit right in (like the brass C8 pill that is also sold by Fasttech, or the pill from the Uniquefire UF-T20). But it is handy to use that spacer if the led is XML. If it is not xml, like the xpg2 that comes with this group buy, the centering is a bit trial and error when screwing down the reflector.

The switch is also exact the same (brandless) switch that is in the Ultrafire C8 host. I guess it is a good switch, it does need some soldering and copper braid when used with high amps.

I tried a C8-pill that throwed 108 klux@1meter in the Uniquefire UF-T20, and 90klux@1meter in the Ultrafire C8 host, in this C10 host it is 93klux@1meter. Unlike in the C8 host, I needed the plastic spacer between led-board and reflector to focus the led well (nice, makes centering easy if using a XML-led, -it was the usual fiddling getting the led in the middle with the XP-G2 led that I used here- , and it gives more clearance of the solder connections). And as expected from the reflector having the same diameter as the C8, the throw is the same as the C8. But because the reflector is a bit deeper (has a bit shorter focal length), (without loosing throw) the hotspot is a bit bigger than the C8, which is nice I think. The spill is less wide than the C8 of course.

The reflector works well enough, but shows some rings when looked from the side a bit, as usual with cheap reflectors:

All in all, I like it :-)

118

It looks like you’ve got a de-domed XP-G2 in there. How hard is it driven?

119

It is a dedomed XP-G2 3C (this led was my first dedome ever :-) ), the driver is a 3,05A Nanjg 105C (I measured max 2.95A with this pill).

120

Sweet, thanks. I had been guessing that the BLF C10 (as built by 18sixfifty, de-domed XP-G2 at close to 3 amps) would probably get about the same lux as a Fenix TK75 (92 kcd), and it looks like my guess was probably really close.

I’m tempted to grab a UF-T20 too, if the pill is interchangeable and it gets a 108 kcd beam at the same power. Been wanting a laser-like aspheric for a while. Where did you get yours (given how clones work, I don’t trust that all UF-T20 units will use the same pill)?