Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

Advice for First laser project please

RA_pierce

RA_pierce

0
Joined
Sep 16, 2007
Messages
3,667
Points
113
So I have finally accumulated enough cash to pay for a good DIY laser project. I am willing to spend $200 at most, preferably less, but I want this to be a BAMF laser. Right now, I'm just trying to figure out what parts and tools I need.

I'm planning on using an open can red diode (if I can get enough power for a good price an IR diode would be ok too) in a Meredith module with a glass lens.

The host I want to use is a flashlight roughly the size of a mini maglite, but about 2cm longer. By the way, I am NOT trying to do the KipKay shit.

First, I want to determine the limitations on this project due to heatsinking capabilities. The entire flashlight is anodized aluminum and will fit the Meredith module perfectly.
If an open can diode would produce too much heat I would settle for a 16X diode just because I really, really like the host.
If necessary, I could make a heatsink myself out of washers and crap or maybe buy a custom heatsink from someone who knows how to make 'em. But that would require me to change the entire design I had in mind.

As for a driver, I would really like to use a pre-made one if I can; maybe from a leadlight or anything that would supply enough current with an adjustable pot. I don't mind making my own but I don't want to screw up and kill my diode. Also, driver boards from laser pens tend to be smaller and more compact than DIY ones and I want to save as much space as possible. I also need to buy a new multimeter and soldering iron; the ones I have are really old broken pieces of shit.

The flashlight is designed to take AA batteries but I would like to use a single cell rechargeable if possible. I read something about 3.6V Lithium batteries that look like AAs but I have yet to find any.
I have also considered CR2s. I don't know the dimensions of these but from what I've seen they appear to be about the same diameter as a AA battery. If those fit, I'll use 'em.

I am mostly trying to build this laser around the host because it is aesthetically pleasing, compact and there are a few other neat tricks I will implement once I have the diode and driver installed.



So these are the questions I would like answered; any other comments are appreciated:

+Would the module and the flashlight alone be able to dissipate enough heat for a decent duty cycle (with an open can diode)?

+Can I use a pre-made driver board from a leadlight?

+Can anyone recommend a good and relatively low priced soldering tool and/or multimeter?

+What diode would work best with what I am trying to accomplish?

+What battery can I use?

Thanks for any help!
 





just starting a project myself but ill share what ive learned so far. check for answers below.

if you want to make something bigger....:
http://cgi.ebay.com/1000mw-808nm-la...ryZ53141QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
http://www.mi-lasers.com/cgi-bin/shopper.cgi?search=action&keywords=diode_parts

+Would the module and the flashlight alone be able to dissipate enough heat for a decent duty cycle (with an open can diode)? depends on thickness and material. if its aluminum it will help reduce heat but if the diode is powerful enuff youll need a heat sink.

+Can I use a pre-made driver board from a leadlight?dunno youll have to ask 1 of the gurus...

+Can anyone recommend a good and relatively low priced soldering tool and/or multimeter?radio shack

+What diode would work best with what I am trying to accomplish?if your not going to use any heatsinks or just use it for a min or 2 at the time use a lower powered diode. the 16x u mentioned would probably work

+What battery can I use? that all depends on the driver you get
 
I'll try to answer a few questions.

I don't think you will be able to use a driver from a leadlight to power a red laser. Red laser diodes require higher voltages to laser than an infrared diode does.

If you are wanting a really powerful laser, open can diodes are they way to go. Those things have serious power. If you end up using an open can diode, white matches will be no problem for it.
 
+Would the module and the flashlight alone be able to dissipate enough heat for a decent duty cycle (with an open can diode)?
If you're going to use an open can then you are going to need a heatsink, normally I would recommend using jay's heatsinks with the MXDL, but since you love this host so much, then you have to make your own heatsink, or go to a hobby shop and look for one that fits your module. Check this thread for how to make a heatsink out of washers: http://www.laserpointerforums.com/forums/YaBB.pl?num=1204493878  And this one for a burner from which you can easily harvest an open can: http://www.laserpointerforums.com/forums/YaBB.pl?num=1202158967/0

+Can I use a pre-made driver board from a leadlight?
If you don't want to make the DDL driver, you can buy this one: http://www.laserpointerforums.com/forums/YaBB.pl?num=1191898669/0  It comes ready to drive an open can at 340mA, (it doesn't have a pot) all you have to do is to solder a capacitor to the diode's pins. If you were using a 16x diode, then all you'd need to do would be to place a 33 ohm resistor in parallel with the laser diode to limit the current to approx. 250mA. Now, you can put in more than 340mA into an open can, the sweet spot is 420mA, but if you want to go that high, then you'll have to make a DDL driver. Since you say your host takes AA batteries, then one 3.6v battery should be good to power the driver which I linked above, for the DDL driver you're going to have to put in two 3.6v batteries to make a total of 7.2v.

+Can anyone recommend a good and relatively low priced soldering tool and/or multimeter?
I recently bought this multimeter and it seems to be pretty good (good enough for me ;D) http://www.sears.com/shc/s/p_10153_12605_03482345000P?keyword=crafstman+multimeter  And for the soldering iron: (I don't know if this is good, but it's cheap ;D) http://www.radioshack.com/product/i...ng+iron&numProdsPerPage=100&parentPage=search

+What diode would work best with what I am trying to accomplish?
I already posted a link to the thread about the burner from where to harvest an open can really easy. But if you have trouble fitting a heatsink into your host, you can always buy some of SenKat's diodes, (you don't need a heatsink, but you'll need to have short duty cycles) the only problem is that no body knows if he's now selling the good diodes again, or if he's still selling diodes from the bad batch. So I would wait for someone to confirm this. Now, the second option is to buy the burner linked above, but instead of using the open can red diode, you can use the IR diode and leave the open can for a latter project (since you said an IR laser would also be ok) the IR shouldn't generate too much heat in a short time since it doesn't need a lot of current, but for this IR laser you absolutely have to use the DDL driver, since you can only limit the current to 250 on the other one, and that'd be too much for the poor IR diode. You'd have to drive the IR diode at about 140mA to get a good life out of it, but you'd only be getting about 80 - 90mW, which is still good to do some burning, but not as powerful as a 16x, much less the open can beast. ;D Oh, and the most important part, you absolutely need goggles if you're going to make the IR laser, I'm sure you understand why ;) here's the safety goggles GB thread: http://www.laserpointerforums.com/forums/YaBB.pl?num=1202742071

+What battery can I use?
Here's a pack of two 3.7v AA sized protected lithium batteries:
http://www.dealextreme.com/details.dx/sku.3435
And here's the charger:
http://www.dealextreme.com/details.dx/sku.4151

I hope this is enough info, it took me like 30 minutes to type this post. :o
 
Thanks for all the help guys! :)

A few questions regarding the diode:

If I use an open can would it generate enough heat to kill the diode in a few seconds (if the only heatsinking material is the aluminum flashlight and Meredith module) or would it be ok to run it on a ~1 minute duty cycle?

The flashlight body is about 1mm thick all around and the Meredith module looks better for heatsinking than an Aixiz module...
The way I plan on building this allows the head of the flashlight to be removable- so when the head is attached it adds another nice chunk of aluminum to the module- which should improve heat dissipation.

I read some posts about "long" and "short" open cans... is there a difference between the power output of the two or are they identical?
 
I'm not exactly sure how hot the open cans get since I haven't used mine yet, but if you don't put a heatsink on the module, the diode will not have a very long life. I don't think the flashlight head will be enought heatsinking, and if you wanted to use it as a heatsink, the module would need to have a tight fit in there, or you'd need to use thermal epoxy. As for the long and short open cans, no body is really sure about the difference between them, I have a short open can and I'm thinking of sending it to Dr. Lava for testing, but first I need to get my hands on a long open can, just in case the other one dies during testing.
 
Hmmm... what if I drive the diode at a lower current? Say maybe 300-350mA? Can I still get good power?
If I make a driver with an adjustable pot I could just test it at different current and just set it to the max it will go without getting too warm.
Will an open can driven at 300-350mA yield higher power than a GB diode at 250mA?
 
RA.... I think for a first time DIY you should start with some thing that has been done before to under stand how things come together.  After that you can experiment and modify what you have to meet your specific needs.  From your post you have a veryspecific need and alot of unknowns so why not start with a Dorcy like build.  This built would not cost you much either;

flashlight: Dorcy or like with a driver (about $25)
cap: $3
open can LD: $24
Aixiz housing: $6
shalf collar: $3

I did my first DIY laser with a Dorcy Metalgear and it was fast and easy.  It came out very clean (with a heatsink) and looks professional too.  I can't remeber how many mA the driver put out but I can smoke a black leather shoe about 4 feet away in 4 seconds.  I do not have any means to post picture of  the built but if some one does let me know and I can send pictures of it.  

Le
 
RA_pierce said:
Hmmm... what if I drive the diode at a lower current? Say maybe 300-350mA? Can I still get good power?
If I make a driver with an adjustable pot I could just test it at different current and just set it to the max it will go without getting too warm.
Will an open can driven at 300-350mA yield higher power than a GB diode at 250mA?
Click to expand...

An open can at 350mA's will only give you a little over 200mW's. Unless you have a Meredith glass lens. Then maybe about 250mW's. I am getting 208mW's from a Sony/Senkat diode (one of the good ones) @ 294mA's. So, it seems that if you go with an open can, the idea would be to get more power than the Sony/Senkat diode. Thus, more current to that thing! 420mA's is pretty nice. Heatsinked...
Jay
 
RA_pierce said:
Hmmm... what if I drive the diode at a lower current? Say maybe 300-350mA? Can I still get good power?
If I make a driver with an adjustable pot I could just test it at different current and just set it to the max it will go without getting too warm.
Will an open can driven at 300-350mA yield higher power than a GB diode at 250mA?
Click to expand...

The Aixiz module does provide adequate heatsinking for any of the red diodes, but the open cans do get quite warm. I would keep it at 30 second duty cycles if running it at 400ma's.

IMO the best open can mod right now is the one that uses the MXDL and Jays heatsink. I would use a glass lens, Aixiz is now selling them on E-bay. Or go with the Meredith module with glass lens. Jay's heatsink provides all the cooling you will need and you can run it for a long time before it gets warm. But even with a TEC, I don't usually run my labby for more than a few minutes at a time. Also if you are using an open can or closed can forget the pot...you don't need it unless you are building a labby to experiment with. We already know what the LM317 will supply to the diode depending on the resistor used between the adjust and output pins.
 
the more i read, the more i want to finally make a red burner. im just worried that i would screw up the driver thing, my soldering skills arent very good, of course, i need a better soldering iron, i bought a $5 one at radioshack
 
Gazoo said:
IMO the best open can mod right now is the one that uses the MXDL and Jays heatsink. I would use a glass lens, Aixiz is now selling them on E-bay. Or go with the Meredith module with glass lens. Jay's heatsink provides all the cooling you will need and you can run it for a long time before it gets warm. But even with a TEC, I don't usually run my labby for more than a few minutes at a time. Also if you are using an open can or closed can forget the pot...you don't need it unless you are building a labby to experiment with. We already know what the LM317 will supply to the diode depending on the resistor used between the adjust and output pins.
Click to expand...

Yeah, I am gonna use the glass Meredith. I would do the MXDL mod with Jay's heatsink but I just really like the host I have. The duty cycle isn't a big deal to me even if it is only 30 seconds. The driver is really the only concern I have. Extraction seems pretty straightforward and I've practiced on some broken/ unused DVD drives... Heatsinking doesn't seem like a very big deal with a duty cycle. The reason I want the pot is so that I can adjust current according to what power level outputs the most power with the least heat. I can't use the DDL driver because it requires 6V and I only have room for one AA sized battery which means I can use one of those 3.7V Li battery.

What if I remove/replace a resistor on a leadlight driver with one of a lower value? Don't they supply about 350mA with the pot maxed? Would this work: http://www.greenlasers.co.uk/forum/viewtopic.php?f=4&t=13
???
 
Gazoo said:
IMO the best open can mod right now is the one that uses the MXDL and Jays heatsink. I would use a glass lens, Aixiz is now selling them on E-bay. Or go with the Meredith module with glass lens. Jay's heatsink provides all the cooling you will need and you can run it for a long time before it gets warm.
Click to expand...

Well said Gazoo! We took Daedal's MXDL build, super charged it with your open can diodes, and finished it off with my clean, functional heatsinks! What a combination! 300mW's in a handheld!
Jay
 
man, the more i get into this hobby, the less powerful i think that my lasers are :P a homemade 300mw laser is way better than a $200 125mw from "that company"
 
You must log in or register to reply here.


Back
Top