Behold! The Lasertron Cometh...

Doom and gloom aplenty right now.
Well to take your mind off that I'm documenting the construction of a targetting laser.

www.flickr.com...

Targeting Laser

To start with I am by no means an electrical genius or a whiz.
But I have the tools provided from a master inventer so let's give it a try

Ok to start with I'll provide a little background.

About a month ago I bought a real nice Crossbow.
Which is pretty cool and does the job.
Then I saw a few things about lasers and how they are now getting very powerful and are untouched (mostly) by the bs establishment that wants us all tucked into bed and read stories by nanny.

So apart from fire-starting I thought it would be a good idea to mount one onto my Crossbow.

Now I know this isn't really a pure survivalist tool, after all you don't need one to be a good shot.
But besides the quicker target aquisition, firing from the hip and of course, nothing can discourage and attacker than if they see the burnin' beam of destiny upon them there is more to it.
It has the added edge of being more than capable of blinding an attacker should the situation demand it.
As it isn't about being a killing aid or blinding people. That really is a SITX dark scenario.
This is about it being more of a versitile survival tool as well.

Besides which, even as survivalists, we're allowed some 'gucci' kit to enjoy

From Concept to Creation

So the idea was set and now it was time to put what may of been a pipe dream into action.

So I pulled out all the tools I needed and did some checking.
I visited a handy little website (details available on request) which was set up by some free-minded guys from the laser community. Now these dudes are not what you call survivalists, but they know a good laser when they see one and are oracles when it comes to what diode can take what voltage etc.
So from them I bought:

2 x diodes (originally harvested from a PS3, they are DVD RW capable, which should give an indication of the power).
The diodes were also pre-mounted into a metal housing. This is handy, and acts as a bit of a mini-heat sink as well.

Now you may of seen the youtube man who harvests the diode and buzzes about with his:

www.youtube.com...

This is a rough example. It will work BUT the diode is very unstable due to the voltage not being regulated. I won't go into specifics but the spiking effect (which batteries do from time to time) will destroy the diode.


2 x drivers - Very Important. Basically these are a tiny circuit board with capacitors and resistors plus a pot.
Which allows you to *adjust* the current and therefore the lasers strength / beam power.

1 x 9V battery

Total Cost including Shipping from the States:

$94

The reason for 2 is in case I blow the diode or driver on the first attempt.

Originally I was going to strive for an integrated housing with the battery, but getting a housing small enough to fix on the crossbow, yet large enough to take all the parts was near impossible.
Factoring into this conundrum the fact that I needed a housing which would be flush with the crossbow.
I will admit, the spec ops guys with these very exlusive units mounted onto their weapons also influenced me. They (according to my bro) used lithium based batteries and be-spoke designs though.
My laser or 'The Lasertron' as it was dubbed would be almost entirely from existing torches and retro-fitted into them.

So the search began as I awaited the arrival of the elusive diodes and drivers.
The biggest obstacle was sourcing a housing that would sit flush against sighting system.



Hunt For The Housing...

Now I do not expect to achieve William Tell-like accuracy from a home-made targeting laser but let's not kid ourselves, mounting a maglight or anything with a 'bulge' was not going to give reasonable accuracy.
So the search commenced for a symetrical housing.

With the mindset of seeking for an all-in-one wonder housing in my head I roved and roamed the murky online world of Ebay. Nothing suitable.
I sized up the sighting area and it needed to be no bigger than 4.5cm. Anything more and it'd interfere with aiming down the sight.

I was, at one point, doubting the project could even be undertaken without major £££ and heartache. With the diodes and drivers winging their way from the US I wondered if they'd be doomed to the dusty garage to muse on what might of been!

Then one sunny day I was rooting through the pantry for the 5th time when I found one of those old square shaped torches with the concealed flip-out bulbs.
You don't get them in the states much but here in the UK they were in vogue about ten years ago.
This got me thinking. It seemed large enough for the whole shootin' match.
So I stripped it out and mulled over using this.
Too small.
I unleashed the drill and dremel and got stuck in.
Still too small!
I cut out the flip-up bulb thing.
A tighter than tight fit.
More drilling, clipping and swearing.
It might fit.
Tried it.
No it didn't.
I'm at the end of my tether. My room resembles a mad fabricators workshop and # is everywhere!
It was too small for the diode, driver, wiring and battery.
But not the diode and driver.
One of the Northern Alliance dudes popped up on msn so we had a palaver about it.
'Why not mount the thing separate was the call!'
You know what, I think i will.
All it takes is a fresh idea and a rocky, impassably mountain becomes the tunnel of groove
So having gone over this we agreed that why not separate the housing from the battery cell, carefully plumb in the wiring as neatly as possible.
Now initially I was bull-headed about keeping everything integrated and in one housing as I keep gabbling about.
This cuts down on the 'more bits to get lost and in the way' factor and it 'looks cooler.
But there was no other way.
Things then started to fall into place.
I wanted functionality and field-user-friendliness as a hallmark.
I could live with soldered wiring and semi-fixed laser housings. I couldn't live with a hard-wired and soldered battery housing.
The battery would have to be a 'pop-open the case, unclip the battery' and put a new one in.

So off to the lunatic town electrician for parts.

This guy is a real lunatic amoung lunatics. I'd like to say he's a friendly, quirky eccentric kinda guy but alas not this guy

[edit on 26-9-2008 by WatchRider]

[edit on 26-9-2008 by WatchRider]

Ooooh! shiny Lasertrons! My ancient BSA Meteor would look grand with one strapped to it's home-made 'picatinny rail'

I'll swap you for a homebrew 12V 8 magnet/6 coil wind-genny alternator...how's that sound?



..just dial 01-811-8055 and Cheggers himself will take the call!



[edit on 26-9-2008 by citizen smith]

Cant seem to open your link near the top of the post. However, anything that makes targeting faster and easier is certainly high on my survival list. Even if it is "gucci". The ability to hit a mark while running, off balance, can easily save your life. I recently added a laser system to my daily carry hand gun and enjoy it so much, will be upgrading all of my handguns in the near future.

sod the crossbow-sights...how about combining a disco glitter-ball with your CD-drive laser diode-set for a literally dazzling area-denial system?

(Original Post Continued)

So I roll into the town electricians place, a dusty, musty place with mostly audio electrical hardware.
For all his crazy style and attitude he is the last of his breed in my town. All other electricians have either gone or turned into big silly stores like Dixons or Currys. For the humble, independent sparky on the move, cheap spare parts of an electrical seem threatened

I order up a simple side-to-side switch, a metre of wire, and 9V battery connector.
Amazingly the mans craziness seems to of passed, for he does not interrogate me on what it is I want the parts for.
But my luck does not hold, rummaging through various drawers he suddenly starts with the questions.
I play him off claiming to be on an errand for my (late) father

So about $3 later I have nearly everything apart from the primary housing.
The housing that will take the diode housing and driver.
I buzz into the £1 Shop. I nearly decide on a nice slim-line torch not unlike a mini maglite. But its length is too great. 7cm is a bridge too far.

The next shop is another blank.

Third time lucky - It sure is! The third shop I try has the perfect housing.
Symmetrical, black and about 4 cm in length.

$4 later I am the new owner of a torch. If only the seller knew what I planned to do with this!

Back to the techno workshop at home an I get to work.

Here is everything:



Going into detail:

This is the primary housing.







For modding and sorting this for the diode and housing I had some real fun and games. Removing the existing bits and pieces was easy enough.
I kept the plastic lens as a weather seal.
The diode sits fairly well in the new housing but its not a snug fit:
The solution for can be several ways. The easiest was from a method used in the construction industry. That is to use 'shims' to fill the gap. Which is what I did.
A leftover hobo can I used for the shim.
It slid in fairly well then I bent it carefully to avoid touching the diodes prods.





For screwing it shut it was not so perfect though, the diode almost means its too big, but it takes a full turn. I'll have to environmental seal this manually. As long as it sits straight is what I'm aiming for.

The next step was to insert the driver into the hollow tube of the old battery compartment of the housing. Again this seemed straightforward on first sight but it wasn't.

Too big was the cry! So using a scalpel blade I carefully 'cut' a series of notches and using the pliers I removed enough for it to go in.
I had to be really careful though as the thread was microns away. Any mess-ups here and the whole project would be royally fcked!
All went well and the housing slid in nicely:



Leaving this I went back to the battery housing.

This is the battery (secondary) housing. The one that most of the work has been done to.



Side view:



Now it's time to mount the switch. Without it I'd be left with an 'always-on' laser and inserting / removing batteries to turn off burning lasers is not my thing.

As a basic electrics kind-of guy I was a bit over-eager and wired it up wrong TWICE! But Having a multimeter to check the voltage is a wise thing whenever you are getting around to the serious business we are coming to now.

The switch is a side to side, slide switch
Basically you have six terminals with the slide switch covering 4 of the 6 terminals.
You wire the input and output wires (input from the battery, output to the other housing) like so.


Legend:

Terminals= x

Slide Switch= S
Slide Switch Gap area= (S)

Input / Ouput Wires= I , O polarity = + -
I O
- -
x x x
(S) S S
x x x
(S) S S
+ +
I O

You need your soldering iron now, and solder the wires to the relevent terminals. Check the voltage buy connecting you battery. The proof of the pudding comes when you have to check the OUTPUT wires voltage.
With the switch ON you should get matching voltage from the input and output wires.
The the switch OFF you should get zero voltage from the output wires only. Input wires will remain the same.

Warning:
Make sure you have no loose wires touching each other or crossing terminals.
You will be working with a live circuit when testing your rig soon and you are working with lasers. A stray beam when from a dodgy wiring could (in theory) cut into your eyeball. This will ruin your day, your week and possibly the rest of your natural life.
I have read too many grim stories on the laser geeks forum to relax at this point.
Safety goggles (which I wear) reduce the risk but laser goggles work the best if you are unsure.

This level of this laser is approx 180 - 200 mW power in the red spectrum. This is not the most lethal laser out there, but consider that the piddly laser pointers in the shops are only 5 mW you have a veritable cannon among lasers.
They go up to 500 mW!
Anything above 50 mW is seriously dangerous for your eyeballs.
For Sitx you obviously won't be goggled up but for stripping down and testing etc you know what I mean
Warning over.

Ok so input and out put wiring in order it was time to tidy the wiring and tape the loose ends shut.





Which is where I am up to now!
Later on today I'll start on the primary housing and get that soldered and ready for the BIG Hook-Up.

See you later for another quirky episode of -

"The Lasertron Cometh"

Ok I lied I'm back in flash!

The next problem was the mA rating for the board and diode.

Now I must mention that the driver does much more than just allow you to adjust your laser into a burning tool of futuristic abandon.
It also regulates the voltage and current and keeps the diode from burning out.

Now, in my carefree groove I was going to hook it all up and then just fire it up, watch how bright the laser was, then adjust it.
According to the laser oracle's on the other forum they stress otherwise.

It was time to do some research.
Handily the website I got these from have detailed files held for the diode and driver.
Using these I was given clear instructions and specs on the diode.
The max rating (on paper) for the diode is given as 170 mA MAX!
Using the multimeter to measure the resistance (in ohms) with the Pot Resistor set to maximum (meaning the lowest laser power available).
I was taken aback to see that (assuming the 9V is fully charged) the laser would be at least 30 mA over the max rating. That is at about 205 mA.
You can actually buy a load tester to do this, but using Ohms law and dividing the voltage by the resistance you get the current. This is slightly more art than precision but it does the job and you get the right picture.

So know there was a wall in the way.
Much buzzing was exchanged between myself One of the Northern Alliance bro's on whether to hang fire.
This was pretty much make or break time.
Either I mothballed the project and await a higher powered Diode (which would take 10 days to arrive) or I could go with the flow and see what's next!

I plugged for the latter. After I made up my mind I took a line of enquiry which took me to the reviews section of the diode I was running.
My maverick instinct paid off, the reviews spoke glowingly and in near mythic admiration and amazement at it's capabilities and power threshold.

Here's some from the lords of lasertroning -
"I run them at 294mA's using a 4.3 ohm resistor in a DDL driver. This gives me over 200mW's! According to Mike's graph, they could be pushed more! Of course, at that power, you want a good heatsink in there..."

He goes on to claim a 14 hour burn time (over three separate sessions)

Having read the reviews I'm tempted to ease back the resistance on the driver.
But there are merits to keeping the power on minimum.
Besides less potential eye strain/damage if you stare at the beam (which is possible if you are protractedly aiming and 'like' the look of the beam). It uses less battery power AND doesn't strain the diode.

For those who are need a refresh, this is a close up of the driver.



The adjustable pot. (adjustable resistor) is the bit with the tiny white X (for a jewelers screwdriver).
Anti-clockwise increases the resistance (lowers current), clockwise decreases resistance (raises current). Right now mine is at MAX anti-clockwise which is about 43 ohms.
For the maximum overdrive dudes out there if you crank the pot all the way clockwise you end up with a paltry 0.3 ohms resistance which givesand enough Amps to melt your diode and driver into another dimension

This is the diode (as it looks without coming in the Aziz housing)



[edit on 26-9-2008 by WatchRider]

mmmm, I wonder if I could mount one on my catapault....



Probably not.

The final chapter.

Soldering the driver to the diode:

Soldering was a pain, very tricky for due to the small circuit board and tiny diode wires.

Got there in the end though.









Done all the soldering and re-housing necessary.

Wired it all up, got the battery fired up, safety glasses on and .... Nothing!

Not a squeek!

So I re-opened the housing and checked the wiring for shorts...
None that I could see.
Checked the diode was getting voltage... It was.

I was on the verge of changing out the diode when I wondered if turning up the pot might fix it.
I thought it was a crazy groove to try but I turned the pot up a notch, nothing.
Half a turn - Let there be light! A sputtering light of red. 3/4 of a turn, stronger.
A full turn - We have the burnin' groove a-go-go.



Time to hook it all up and let the Lasertron take its rightful place in the targetting world

Gaffer tape a go-go

Battery Cell housing in place and ready.



Primary housing.



Joining the battery housing wires to the drivers / diodes.
I was going to crimp the two sets of wires but went for the tried and tested solder, just to be sure.



Final plumbing in. She's ready to dance!




Testing

The beam is powerful.
Headaches are certain if you fire this laser off indoors without glasses.
Keep it for outdoors and at ranges beyond 5 yards and you should be fine.

All this took me 6 days from start to finish (say about 12 man hours and about $100.
To buy one commercially is about $600 from the states and they are a lot bigger and more cumbersome.
Always better to be a craftsman than a consumer with such things.

Let me know if you want to know more on the laser groove...

[edit on 27-9-2008 by WatchRider]

This is interesting. I was wondering though, why not use a pre-made housing from a ordinary laser pointer? Like
instead? I'm sure there is a good reason but I had to ask
I'm guessing your not from the states and may have a hard time finding certain things, here is a really nice site for this, www.allelectronics.com... they have absolutely everything you can imagine, want 10,000 Nintendo Power/Reset buttons? no problem, 0.3 cents each, 100 electroluminescent strips? $2.50 each or even peltier effect thermo-electric pads. Its a must-see for this kind of thing.

Fascinating and interesting article, i have been considering fitting a laser to both my pistol bow ( Barnett trident) and my Recurve bow, Its gotta be worth trying.
NR

BTw you may want to try using a scope mounting set and just make a sleeve for the laser to sit in

[edit on 27-9-2008 by Northern Raider]

reply to post by Snift


Ok, I'm at a buddy's house but this is Watch Rider.

It's 6 and 2 three's mate. In other words its swings and roundabouts.
One is just as good as the other.
If you check the size of the diode I've used they won't fit into a laser housing of the magnatude of what you are buzzing on about.
The laser pointer you have shown is typically 5 mW and is on a pressure switch as opposed to an 'always on' application. The button batteries they use also last a very very short time in relation to a stronger diode.
That really is a kids toy more than a targeting device.
The are considered 'out of date' in the laser community.

Mine is 200 mW and a bigger beast entirely. Hence the external power supply.
Hence one of my reasons for a customised approach.
Also this is very much a survivalist approach using the everyday items to make the job done.

Also the driver would probably not fit in either.
I appreciate the link to the US shop but even in merry old England we have access to a little curiosity shop called Maplin Electronics

Don't want to sound like I'm having a go at you dude but just telling it like it is

Chewbacca had this idea originally and it worked for him.

"Aaarrrrgggh Grrrrrrrr Arrrgh Urrrrrghh Oooohh Arrgh...!"

He said he wants 40 percent.

Brilliant work...particularly in the gaffatape-department...all thats needed is a snappy-sounding evil-deathray type of acronym

how about "Diode Enhanced Aiming Device" ?

...or DEAD for short as anything you aim at will be very shortly

(edit to add..)
Also, as you removed the rear iron-sight to mount the red-dot unit as you described in your 'crossbow build' thread, maybe you could re-use it to mount the laser housing onto, giving you the ability to fine-tune horizontal/vertical range-sighting so that you'd guarantee an 'on-the-dot' hit?



[edit on 27-9-2008 by citizen smith]

Maybe you can use velcro strips to hold the laser on....
Woolworths do the sticky velcro for a couple of quid.

It would look better than gaffa/duct tape....

[edit on 28-9-2008 by Dar Kuma]

Originally posted by Snift
This is interesting. I was wondering though, why not use a pre-made housing from a ordinary laser pointer? Like
instead? I'm sure there is a good reason but I had to ask

I'm guessing your not from the states and may have a hard time finding certain things, here is a really nice site for this, www.allelectronics.com... they have absolutely everything you can imagine, want 10,000 Nintendo Power/Reset buttons? no problem, 0.3 cents each, 100 electroluminescent strips? $2.50 each or even peltier effect thermo-electric pads. Its a must-see for this kind of thing.

Not a bad question.

Here in the UK things like the diode and driver are hard to source without harvesting from existing DVD RW and the like.

But we have most of the other stuff like switches and wire through Maplin electronics.
So even though this is merry England we still have the stuff the States has (most of the time )

The fact that they tend to have an inferior diameter for the diodes I use (due to them being 200 mW) is the prime factor.
Other reason is the batterys tend to be dinky button ones. These are underpowered for a 200 mW diode alas. You need a minimum of AT LEAST 6v Lithium or 9v.
You also would have to customise a switch as many are a pressure button activation as opposed to an 'off hold or on hold switch'.

I can see a li'l flaw with your current set-up...having to reach back with one hand to the buttstock to switch the laser to 'always on/off'

This would present the problem of giving yourself away to a potential target before you take the shot, and if you are concealed and taking a snap-shot, making yourself visible to directed return-fire..the other is that there is the possibility of leaving the unit 'accidentally on' draining the battery of precious power...and in the field you can't guarantee a chance to recharge when it will be most needed!

The addition of a simple push-and-hold button on the pistol grip/forestock (depending on your shooting style) at the juntion of these wires would be a perfect solution

Originally posted by citizen smith
I can see a li'l flaw with your current set-up...having to reach back with one hand to the buttstock to switch the laser to 'always on/off'

This would present the problem of giving yourself away to a potential target before you take the shot, and if you are concealed and taking a snap-shot, making yourself visible to directed return-fire..the other is that there is the possibility of leaving the unit 'accidentally on' draining the battery of precious power...and in the field you can't guarantee a chance to recharge when it will be most needed!

The addition of a simple push-and-hold button on the pistol grip/forestock (depending on your shooting style) at the juntion of these wires would be a perfect solution

Yep I hear what you mean mate.

This was something I planned for and in the long-term I will be looking at a remote switch.
I'll use the existing wiring left over and plumb it in to where the battery cell and primary housing connection is via another soldering session.

I will need use a more robust remote switch than the one I bought for the battery cell unit though.
Maplins will probably be the next place I visit for electrics spares.

Right now I have already installed a safety catch (of sorts) onto the main switch, this is achieved via a fine strip of gaffer tape across the gate. Just remove manually and she's ready to go

Okay, just been adding (yet more) final touches to the Lasertron.
Basically when you get one of these diodes in a housing like this:



There should be a threaded focusing ring. You can just see it if you look at the where the strip of gaffer tape is (which is there to keep it from defocusing when I insert it into the master housing).
Here it is back in the master housing:



Basically they don't ship the diodes out pre-focused and you'll find that far from getting a Metal Gear Solid type 'dot' focused laser point, you have a tennis ball shaped thing instead.
Now, as a laser goes further it loses focus and becomes bigger anyway but at close to medium range you want it focused like this:



Pretty neat eh? It certainly looks the part!
I'm currently resisting the temptation to run around like a Foxhound spec ops dude in the garden!
I'll try lighting some matches with this bad-boy and upload it to youtube later

According the aftersales dude in the States who sold me this, when I asked him how dangerous these were to look at he said and I quote
"Direct beam hits, and reflections are dangerous –just viewing the beam is perfectly safe."

I partly agree, but I viewed the dot with the naked eye indoors and did feel / imagine a slight sensation to my eye afterwards. Not painful or vision impairing. But like a slight sensitivity. Probably nothing but wise to respect these devices as tools and weapons more than toys I think.
Outdoors this does not occur due to the ranges involved though (unless you go sticking your head down the diode or something!)

I've got another Diode and Driver!
With this and the housing I've just source it will be a handheld laser for pocket use. But that's another thread

Any way to make a adjustable beam with it? I know on a ps3, its adjusted with a electromagnet so thats no good, maybe like the eye-peice on a microscope to adjust the focus.
If you can find one, a green diode would rock in that thing, just the fact that you can see the whole beam without needing it to reflect off of particles or a surface and, well its green

Yeah, just adjust the focusing ring and the beam will go either bigger or smaller.
You see the shiny silver inner-housing here:



Well that is your focusing ring.
Normally some guys have this as the housing. I've had to split mine in two and marry it up to and inside a separate, external housing due to size limits for the driver circuit.

So for mine though the focusing ring is inside the black housing for protection and weather resistence.
But yes you could have the internal housing on its own for quick adjustment

Green beams, they don't appeal to me really. Yes, you can see them at night and the beam effect is more noticeable, BUT they are useless in daylight. Whereas the red is more of an all rounder in day or night conditions.