[Guest]

Well I mentioned an idea in the chat and it got some response so I thought a thread would make things easier to keep track of.


As soon as the semester finishes up I'm going to see if I can't make an LED weapon light that fits on the factory M/S rail.

Now the goal of this little project is too see if I can design and make a compact, lightweight, reliable, and CHEAP weapon light. Not so much cause I want one or want to sell them, rather just to see if I can make it!

Here's a brief description of what I'm thinking.

1)The unit will sit flush with the muzzle length and fit against the curve of the trigger guard and will sit no lower than 2cm from the bottom of the current rail. Width is going to be as close to the width of the frame as possible.

2) I'll probably use 4 LEDS. 18000mcd (30* focus) @4.5v but they will be run slighlt overcharged at 6v. I've got a few flashlight conversion now running similiar but with 2 of those LEDs and it is pretty dang bright.

3) Power will be from 2 MN21/23 batteries. Not sure what the runtime will be yet. But these things are small and cheap ( 2pack is $1.77 at walmart) Again, I used these in my flashlight conversion. They are roughly 2/3 the length of a AAA and are the same diameter.

4) Body material will probably be fiberglass. Why? Because I have some, I've worked with it before, a mold is easy to make, and I don't have access to fancy injection molding equipment.


What I'm trying to decide on right now is:
a) switch type. Momentary, on/off, combo? On light or remote pressure switch.
b)reflector/lense. I'm not terribly impressed with the pattern the LED's throw on their own but I think an effective lense setup or reflector design is going to be beyond my means while maintaining the small size and low cost.

I'm really open to idea's here, so chime in! Like I said though, it'll be a month or so before I get started. But I may try to get a CAD drawing done of my idea fairly soon, if that happens I'll post up a picture of it.

 

[madecov]

Why not a luxeon ?
A weapon light needs to be bright and have a decent throw
Maybe consider using 1 of the CR123's
Obviously since all the other weapon lights use them there must be something to it

 

[Guest]

Bear in mind that I've never designed a flashlight or weapon light, BUT:

Have you considered a fresnel lens? I know you can get small ones at American Science & Surplus (or the like) for just a few bucks per, normally. Depending on distance from the light source, they can effectively focus a beam (see http://www-personal.umich.edu/~bclee/lens.html for some amusing instances), narrow it for distance throw (as used in lighthouses, see http://lighthousegetaway.com/lights/fresnel.html), or widen it for projection (as described at http://www.noah.org/acidwarp/warper.html).

Obviously, you're not going to use the massive prism array referenced in the second link, but a cheap polymer fresnel lens would probably work more than well enough for this application.

(Note that if you do successfully undertake this project and are willing, I'll be first to sign up to pay you for one)

 

[madecov]

LED's work well with optics instead of a reflector. The problem is you lose all of the side spill.

A reflector will allow for side spill.

for a handgun mounted light I think you could get away with something in the 30-40 lumen range.
Of course all the commercial manufacturers are trying to boost output

On my shotgun I have a 9v light that puts out about 100 lumens

for a weapon mounted light I think you don't really need more than 60-65 lumens but can get away with about 40

 

[FlaChef]

OK I know nothing of lights and flashlight except how to use them.

that said it does seem like there is some reinventing the wheel here.

If it's your intention to do it from scratch and make a custom build then great! I'll probably even order one if it works and isn't too expensive.-

but can you find and use the guts from an existing light and just put it in a fiberglass housing molded to fit our guns?

 

[Guest]

The Fresno lense is a great idea! Thank you, I had forgotten all about those.

Madecov: I agree, and thats actually why I was looking at a lense... to try to get a tighter pattern. I'll have to experiment with lenses and focal distances to get a beam pattern that works well. A reflector could probably work, but I'll be honest in that the design and fabrication for one is beyond me at the moment.

As for why not gut out an existing unit and use a luexon or such. Well... don't have a unit to gut, and they generally are not cheap to buy! Plus what is there to a flashlight really, a battery, switch, bulb, lense/reflector. The lense/reflector is the only part I'm having problems with and is the one part that has to be custom to fit my size requirements.

Plus this little project is just for kicks and giggles.