So you want to make your own LASER?

Alright... Let's start with what you need to get this all done.

• Obviously, wires, solder, soldering gun.
• I'll leave the LD search to you (I'm using the equivalent of a 16x DVD burner red diode from the SenKat group buy.
• This Host (5W MXDL 2xCR123A flashlight)
• A few washers. I used 3 Fender Washers. One I had shaped to size personally and two 1/2" X 1-1/4" Fender Washers. Those were from the Home Depot for 7 cents a piece.
• Two CR123A batteries (3V, and if rechargeable, check the VOLTAGE before you put them in).
• AixiZ module.
• LM317 TO-220 package. Make sure the metal casing is not grounded! (I used the TO-92 package, but it's only rated up to 100mA and thus do not suggest that anyone else use it, but feel free to use it as I did.)
• Resistor pack or singles
• Patience and a light hand

Let's start by taking the entire flashlight apart.

When you take it all apart, you’ll have the following pieces…

• The battery cap
• The battery tube
• The circuit/LED enclosure
• The reflector holder
• The reflector (not needed anymore)
• The glass lens (not needed anymore)
• The lens holder

The only item on interest right now is the little aluminum enclosure that is supposed to hold the circuit and the LED.

Start off by pulling the little circuit out of the enclosure. The Circuit is simply pressed in. Grab a small flathead screwdriver or an exacto knife and pry the thing out of place. The LED is simply placed on there with nothing holding it in place. Desoldering the blue wire from the LED is all you’ll need to do to pull out the LED. It’s a nice LED, and they actually went hi-tech here and used Silver Solder on the joint so the wire wouldn’t desolder on its own from the heat of the LED.

Notice the “circuit” is nothing but a current limiting resistor. The resistor on mine measured in at 3-ohms. Which is WAY out of the 5% tolerance range.

Of course, desolder the resistor and note where the resistor was connected. On this circuit, there is one solder joint that is connected to the positive battery terminal and the negative it connected through the aluminum shell.

So, you took everything apart… In the place of the lens holder try and place one of the fender washers. Notice how it closes on it nicely but it still wobbles all over the place. This is not a fine setup for a laser… So I decided to go one step higher. I bought whatever was the best fit for my uses (I got six fender washers from Home Depot, each measuring 1.25 inches outside diameter and .25 inside diameter, they were 7 cents a piece). I measured the AixiZ module and decided to drill two of them using my half inch drill bit so they fit the outside of the AixiZ module. If you have something more accurate, go ahead and use it.

Here’s the fun part. I grabbed a drill bit slightly smaller than the AixiZ module, and with it I drilled the third fender washer. I then grabbed a flat drill bit and made the fender washer thinner across a half-inch diameter in the middle. Then I used a grinding bit and grinded the excess until I finally had a fender washer that would just barely go around the bottom screw-joint of the AixiZ module. The result is a washer that can be held in place using the lens holder, and it can hold the AixiZ module in place flat inside the flashlight housing!

As you can see in the picture below… it works very nicely!

For our purposes, we now have a circuit that we can do whatever we want with it, and place whatever we want on it, already made to fit this flashlight! So I grabbed one of my smaller LM317 chips and two 10-ohm resistors. The resistors are from the RadioShack bundle pack. I wound the resistor terminals onto each other from both ends to make one 5-ohm resistor rated up to a half an amp. I soldered that in place between the Adj and the Vout terminals of the LM317, and then I soldered the POSITIVE LD wire to the Adj line. Yes, the same place where the resistors attach to, you can just use the same piece of solder.

MAKE SURE YOUR SOLDER IS CLEAN. MAKE SURE THE TERMINALS ON THE LM317 ARE NOT SOLDERED TOGETHER. MAKE SURE NOTHING IS GROUNDED INSIDE THE CASE.

From here, I connected the LM317 Vin wire to the junction on the circuit that corresponds to the positive terminal. Then I connected the ground wire to the ground. I connected the ground wire to a spot on the circuit board that connects to the designated positive terminal on there. It’s the one that connects to the outside ring on the bottom.

If you connected to the PCB like I did and is pictured above:

After pressing the ‘circuit’ in place, it’s important to connect the outside ring to the aluminum body if you connected the wire like I did. You can just place a small piece of solder on the edge, or press a small wire between the PCB and the aluminum housing and then bend it onto the outside ring.

At this point it is smart to connect a DMM in there, place the batteries inside, and try it out to make sure things work.

We now have 2 wires coming out of the aluminum enclosure and heading towards the front of the flashlight. Start by placing the LD into the AixiZ module, preferably using Arctic Silver, then cutting the third pin coming out of the LD. Then place the capacitor and the 1N4001 diode on the back of the LD.

MAKE SURE NONE OF THE CONNECTIONS OR LD TERMINALS ARE TOUCHING THE AIXIZ MODULE WHEN YOU CLOSE IT. There’s plenty of space in the AixiZ module, so you should be fine.

Then place the bottom of the AixiZ module through the wires, then place the fender washer somewhere so that you can still access the wires. Solder the wires in place and make sure you don’t mix the positive and negative wires. Again, and before powering it up, make sure the AixiZ module is not touching anything while you are closing it.

So now tighten the AixiZ module, adding Arctic Silver if available, and test it out… This should be interesting

Place a couple more fender washers on top, then tighten the lens holder. While tightening make sure you don’t turn the AixiZ module in the process. This could snap your wires, or create some unwanted connection somewhere inside

At this point you are probably the happy owner and maker of your own home-made burning red laser! I will provide a video of this thing burning, and it is one hell of a burner.

I hope you all enjoyed it and good luck making your own. If you need anything please do not hesitate to ask. Suggestions and comments are, as usual, very welcome.

GL;
DDL

The Kill Point is now on... I'll see you all later

Hope to hear from you all soon;
DDL

Holy amazing! I wish I was patient enough to do something like that... I'm just going to stick with a riverrock from target for my first DIY red..

Here's a quick video I just snapped a little bit ago... I know... I have a very shaky hand and I can't keep the laser in place worth a damn, it still burns FAST thought! ;D

Hope you like it;
DDL

Another great DIY laser and as always - great explanations!!!

I see these type of batteries now in more and more handheld lights and in the grocery store yesterday. At the store, they were a little expensive. How well do they hold up under extended use?

Jon

Many thanks for the great guide.

I have a couple of questions if you don't mind:-

1) Does the LM317 in the TO-220 package fit okay? It is more of a square type package and seems a bit larger than the TO-39 package. Also in your photos it looks like you are using a TO-92 package?
2) In the parts list it does not have the diode or cap used. Is the cap the same value (47uF 16V) as from your "Homemade laser diode driver"?
3) I will be using the LD from SenKat's GB. With this circuit what will be the current & voltage supplied to the LD?
4) As we have a regulated current circuit how is the duty cycle of the LD? Do we still need to follow 60 on, 30 off etc?

Many thanks.
XG

Daedal - very well done tutorial, explanation, and video as well ! I love to see the innovation, and expertese going into these burners now, you all have far surpassed my expectations from the very beginings with your inventiveness ! That is a really nice build you have there, I assume the same as Xgeek - and the didoe is 1N4001 as before ? Now - from the pictures, you simply soldered the diode, and the capacitor across the terminals of the laser diode, following polarity and once together, it all fits very nicely ! One thing I would suggest to some of the folks is to mount those items on the wires themselves, and then run two wires to the laser diode - for simplicity, and to avoid too much heat on the LD - you SAY you have shaky hands, but your solering is impeccable ! :P TURD ! hehehehehe ! Excellent work.....

As far as the CR123 batts go - either batterystation.com, batteryjunction.com, and a few other places sell those batts as low as a dollar each in quantity - and they should last a good while to these diodes, as you are putting in 6v, and HIGH amperage, and only using a tiny amount of it for hte circuit ! :-) Great work, in case I havent said that yet ! :-D

2) In the parts list it does not have the diode or cap used. Is the cap the same value (47uF 16V) as from your "Homemade laser diode driver"?
Okay reading the "Home made laser diode driver" post again I would say they are the same.

3) I will be using the LD from SenKat's GB. With this circuit what will be the current & voltage supplied to the LD?
After re-reading the "Home made laser diode driver" post I found my answer to this (2.3-2.8V going into the diode) (Just under 300 mA going into the diode as a 4 ohm resistor = 312.5 mA and we are using a 5 ohm (2 x 10 ohms in parallel)):-

If I am correct, then looking at the Sony data sheet would indicate the LD is running *between 190 mW - 240mW depending on temperature?

Copy and paste from the "Home made laser diode driver" post for reference.
4) As we have a regulated current circuit how is the duty cycle of the LD? Do we still need to follow 60 on, 30 off etc?
If we are driving the LD with 300 mA then I guess it is best to play safe and limit the on time to a minute or less.

The 3 washers seem to make a good heatsink. On mine I may put AS5 between washers and try and get a tight fit between the AixiZ case and washers to help dissipate the heat.

Many thanks.
XG

These types of batteries were designed for cameras, and cameras draw a much lower current than flashlights and lasers. There have been reports on CPF of explosions using these types of batteries. While I don't mean to alarm anyone, and reports of explosions are rare, it is important to exercise caution.

There are several things one can do to help prevent explosions.

1. Buy brand name cells.

2. Don't let them run down all of the way.

3. Invest in a ZTS battery tester so you can make sure each cell is testing even through the discharge cycle. Unbalanced
cells seem to be a big cause of explosions. So you would want to test the cells before you begin to use them, then periodically as they are being used, depending on usage.

http://thomasdistributing.com/shop/z...8b377400f375f5

4. Read up on CPF for more information. Following is one of the threads and is a good read:

http://www.candlepowerforums.com/vb/...d.php?t=170187

You're very welcome... I just wanted to answer these questions very quickly...

1) I am not sure about them fitting in easily, but I can tell you that there is quite enough space int here to make it fit. I personally used the TO-92 package, but the spec sheet show that it is rated up to a maximum of 100mA and I did not want people using it and having it kill their diodes. I have personally tested mine though and it was on for about 5 minutes and there wasn't much heat from it at all. It could be a special case, or it could have been something else, either way, I'd rather be safe than sorry, and for that I advised to one of the other two packages.

2) The diode and the capacitor are the same ones from the driver guide I had made previously.

3) I am using one of the diodes from SenKat's GB as well. With 5-ohm resistance across the circuit, I have measured the output as very close 250mA. I can testify that this thing is AMAZING!! It is quite the burner as you can see in my video.

4) I am currently still testing that out. But I can easily say that I have had this thing on many times for longer than 2 minutes, with the maximum being around 5 minutes, and I have felt no heat from the diode... surprisingly!! I believe that with any help, these diodes can be driven like this on a regular basis. But I wouldn't advise not cooling it. I am merely trying to push the diode to its maximum and to see how much is enough.

Good luck to all and I hope you guys share your experiences;
DDL

SenKat... I really appreciate your comments and kind words. I DO have shaky hands... but I also said I quickly put them to use when they're not as shaky . I'm glad you like the solder-work I have there and I do agree with you. It is much better to solder things to the wire going to the LD, then solder to the LD only once. As we all know, LD's don't like excessive heat. What I had done there was create that entice concoction and then heated it all once and slapped the diode on there. The diode barely saw 3 seconds of heat... if that.

As regards to the diode, I am using a 1N4001 in my setup, and a 47uF capacitor. I am sorry that I hadn't included that in the guide, and I will amend it all to include the new parts.

Also, just as SenKat said, CR123A batteries are VERY powerful. This circuit is barely tapping their potential, so they are probably going to last a very long time. I can easily say that I have had this setup on for well over an hour, and maybe 2. The batteries, however, seem just as good as new! The video was shot with the batteries when they have been used about that much too. The amount of power in two CR-2 batteries is much too tremendous to be affected by the little power we are drawing here. It will be a gradual fall over, perhaps, a month's use.

The batteries I have are the ones we had gotten from that eBay auction where they were damn near free! I, and a few other, got very lucky. They are the Panasonic ones IIRC.

Thanx again;
DDL

Hello Daedal,
I concur with everything you said. My post regarding battery safety was something I felt I needed to post. Having read the horror stories on CPF, I would feel bad if anything happened to anyone here and I had not posted a warning. My conscience was bothering me. I will feel better using those Panasonic Cells we stole off of e-bay ;D I am thankful you caught that in time for us to get them.

Regarding your measurement of 250ma output, I assume you mean you are driving the diode with 250ma's input? I have found the mw output does not seem to increase when going higher than around 250ma, except for when cooling the diode. I can only guess at this since I don't yet have a meter, and use blue electrical tape and matches to kind of get an idea of what does improve output. I have been able to light a non sharpied safety match at 6 feet.

There is no question these diodes are awesome burners. Even with 160ma input I am very impressed.

Thanx for the post about CR123A batts and their explosive nature. The truth is that anything with lithium is explosive. There have been many reports of such happenings, but all one can really hope is that it doesn't happen to any of us. I believe the CPF guys actually used to overdrive the batteries and then cause them to heat. Heating any battery, as was the case with all those recalls on almost all Sony made laptop batteries, will allow humid air to pass into the battery when the sealants give way. Lithium + water = a reaction you don't wanna be anywhere near! Let's just hope for the best though. A duty cycle not only protects the diode in this case, but the battery as well.

As about the LD's themselves. I absolutely love them. I am glad I got enough to test and play around with. With my drive at 250mA, I was able to light all the 14 matches as shown in the video from across a table 6-feet away. So, I agree with you being able to do that. This is one hell of an amazing laser, and quite the bargain I must admit.

--DDL