What design features or materials makes a light safe from vibration/shock.

Hi folks, I haven't been around for a while so it's nice to revisit the pages I've spent so many hours perusing.

I'm working in the planning stages of a project and I need to find out what kind of LED based light (and what type of batteries/compartments) I might need to meet my shock resistant needs.

At this point I am considering anything from building this prototype from the ground up, to a limited partnership or subcontracting part of the work, or even of simply buying compatable lights and installing them into my "system". I need to narrow this down based on what the needs are and what I am capable of.

I can't go into some details about the specifics of my idea but I can go into a lot of detail regarding ballpark sizes and conditions.

But for starters to get started I need to know what attributes does a shock proof light need to have. What makes it shock proof. Are some LED types and makes less able to do this or is it all about providing superior support within the build.

What kind of shock/vibration? For purposes of comparison think of a system that would be mounted near the muzzle of a heavily recoiling gun such as a high powered rifle or 12 ga. shotgun.

Size wise I am thinking about a 2 AA size light.

What I need to know is, what is the difference between a regular light like say my Fenix P3d and something like the streamlight TLR3 that is on my pistol?

What I want to do is create a system about AA long with an LED that puts out at least 90 lumens but preferrably more and can take some shock.

My idea is one that serves a niche and I'd like to fill this niche with a unique product that has fenix like quality and can stand up to shock. And for all I know the fenix lights, and quarks and all the favorites on the board DO have the ability to stand up to that kind of shock. After all they are not incandescents and they are light. But there are things like stronger springs and closer tolerances in the batt compartments that come to mind to keep things from wearing out or getting beaten up much.

I will say that the light itself must just be a certain ballpark size and the real innovation is how it will be used and mounted. Therefore I do have certain needs as far as a customizable tube that must have certain measurements and other requirements to fit into the parts I am going to have machined for them, or more likely the tube will be built to fit into my specifications and an LED head attached.

I need to screw into the base of this light so it needs to have some meat and a screwhole where a button would be on many lights. Therefore I am leaning towards a tighten the head to turn on the light (like the fenix P3D).

For all practical purposes I need a working head/brain and a custom machined tube that can then be anodized.

But I digress. My main question here as I ramble to myself in public view is which lights and LED's are already shock resistant, and are they shock resistant enough or if not what manufacturing techniques need to be employed to make them more shockproof.

If there are too many then I will just shop for weaponlight heads and make custom tubes for them, but that seems alot more expensive for a product I am hoping to eventually sell after perfected.

I had a 6P on my 12 gauge with a cheap ATI mount, and over the course of over a thousand rounds, mostly bird shot, some high brass, never a problem, until I got curious, and threw the light at a brick wall several times, breaking the filament.

LED lights these days seem to be much stronger. At work (I fix cars) we use high quality LED's all the time, basically beating on them like cops with maglites prior to ASP. I can't remember ever seeing one bust. My research about reliability has led me to internet stories mostly about drivers breaking, and I'd think that they might constitute a typical weak link. Which LED driver brand(s) are the most reliable, that is a question I've been curious about myself for my next Mag build, searching around, finding little info. A good one, burrowed in a heatsink, kept in place by silicone or similar soft but durable means, I would think would be very well off for handling shock.

Before I go any further I'd like to point out that I'm relatively new to LED technology, and welcome being told I'm wrong by anyone who knows better, because I'm trying very hard to learn. But, as far as I know from my mechanical skills, taking it any further for reliability, you simply need to dampen vibration to either components, or the light itself. This could be as simple as a rubber/foam/elastomer or something sleeve over the light, in case of a severe drop related shock or something.

Taking it from there, particularly to try and reduce impact from gun recoil, I believe you need to mostly worry about the integrity of the LED, and the connection to the board and heatsink. Sheltering the heatsink from shock will of course make the heat transfer potential go down sharply. There are soft materials which are purpose built to transfer heat, but they are in a whole different league from the capabilities of aluminum and other solid metals. You could, I suppose, have a reasonably bright LED light with a big aluminum heatsink surrounded by a shock absorbing quantity of foam, stuck inside a larger light such as a Mag, but this would make it larger than you're looking for, or perhaps too dim if it wouldn't be built to overheat.

But the issue is that I don't believe it's necessary to go that far. Modern quality LED lights are already so durable that it amazes me. I would suggest that as a starting point you take several good quality off the shelf or lightly modified lights that are close to your criteria, and test them. Knock them around until failure. This will tell you a lot about what innovations you need for your system, if anything.

This one withstands 100 Gs.

http://www.apem.com/pdf\IZ.pdf

With some work, this link
http://www.ehow.com/how_7554357_calculate-shotgun-recoil.html
can be used to find the G force on the gun.

Actually, it's easier than that. If a shotgun weighs 6 pounds and recoils with 100 Gs there'd be 600# of horizontal force on your anterior deltoid for an instant.
Doubtful.

I can't imagine using foam or materials like that. I want this system to be high quality and solid state. The shock resistance has to be a function of tolerances and methods not foam that will fail under heat or long use. I agree that the integrity of the LED itself is the most important as well as the connection strength to other components. There should also be a solid barrier between the LED or the Driver Board, and the Battery Compartment because the battery is a battering ram in most older cheap light designs.

The heat-sink need not be big and heavy as I want my light to be relatively small in the 90-120 lumens range and the tube and head itself will be sufficient for heatsinking.

I am thinking I will need to refine my specifications and see if one of the fine builders on the board can help me with a dozen prototypes for a fee. I am waiting to receive some of the parts I need to attach my system to so I can measure and test various solutions and refinements to my idea.

I guess this thread is done. Thanks for the replies but I can see that I am going to need to partner with a knowledgable builder for the light portion of this project.

Databyter said:

I can see that I am going to need to partner with a knowledgable builder for the light portion of this project.

Click to expand...

That is supposed to be us.

xul said:

That is supposed to be us.

Click to expand...

Well then, try this one on for size. I am looking for a reliable pushbutton switch that can be installed into the side of the bottom of the battery compartment that is low resistance, ultra reliable, and proven. On/off only, although with some light circuits you could still chose levels with this type of switch by for instance 3 presses within a few seconds. I need something that can be installed into a drilled hole in the side of the tube which will also serve as the basecap of the battery compartment. And yes there is a good reason that it NEEDS to be on the side, not in the McClicky position.

For size purposes think a tube for CR123 sized battery width or a bit wider/or thicker walled tube.

Digi-key, at least in the paper catalog, lists how many million cycles their switches are good for, depending on the current and whether it's seeing a resistive load, a tungsten load or an inductive load.

Databyter said:

I can't imagine using foam or materials like that. I want this system to be high quality and solid state. The shock resistance has to be a function of tolerances and methods not foam that will fail under heat or long use. I agree that the integrity of the LED itself is the most important as well as the connection strength to other components. There should also be a solid barrier between the LED or the Driver Board, and the Battery Compartment because the battery is a battering ram in most older cheap light designs.

The heat-sink need not be big and heavy as I want my light to be relatively small in the 90-120 lumens range and the tube and head itself will be sufficient for heatsinking.

I am thinking I will need to refine my specifications and see if one of the fine builders on the board can help me with a dozen prototypes for a fee. I am waiting to receive some of the parts I need to attach my system to so I can measure and test various solutions and refinements to my idea.

I guess this thread is done. Thanks for the replies but I can see that I am going to need to partner with a knowledgable builder for the light portion of this project.

Click to expand...

Sorry it took me so long to respond, my computer died and I just now managed to buy a new one. Doh!

Anyway, you disagreed with my suggestion of vibration dampening/shock absorbing materials, but suggested nothing in its place. It would seem that you should either be happy with whats available on the mass market, or consider using the specialty thermal/electical insulating and conductive elastomers and foams that are on the market today.

Something to consider is that if an elastomer component in a car such as a seal in a transmission
can take a decade of of abuse at high temperatures and PSI all without ever leaking, it definitely will work in simple flashlight, given appropriate design. If you don't have much knowledge on these types of materials, I agree with you that you should seek outside help.

Something I've noticed is that the flashlight community seems overwhelmingly concerned with brightness and battery life, whereas relatively little attention is payed to serious reliability under severe abuse. It is unfortunate.