Pulsars 2w blue 445nm laser build

Flashlight Modding and DIY Parts
1

Parts List:

Solarforce L2n (grey) - $12.99 + $2 shipping

M140 445nm diode - $59 - Free shipping

P60 style heatsink - $8 + $4 shipping

Mohgasm 1.8a Driver - $9 + $5 shipping

Total cost - $99.99

Extras:

Small chunk of copper or aluminum to sink the FET(?) on the driver

Spring for positive battery contact

Thermal adhesive

Something to wrap the heatsink with for a tight fit into the hosts head

Assembling your parts:

First thing you want to do is collect the parts above. I also added a 16mm blue boot to the tail switch, and a 14mm blue boot to put over the lens when not in use to protect it. Totally optional, but I like my blue boots.

Next, place the diode module into the heatsink and tighten the set screw on the side of the heatsink.

Now the diode will have three wires: red, black and white. I dont remember what the white wire was for, but you will not need it. I cut it off leaving about 0.5" in the driver cavity. I then cut down the red and black leads from the diode to about 1" and stripped about 1/8" off the ends. The red wire goes to D+ on the driver, and the black will go to the D- solder pad.

But first you will Want to solder a spring on to the positive battery contact on the driver. I had one kicking around that I used. They are cheap, and even cheaper if you strip it off a junk driver you got from a cheap light you upgraded. If you are here, and wanting to build a laser, I am guessing you have some mod supplies around.

Next up, heatsink the FET(?). I had a small piece of copper bar that I got from the member here that sold me the driver. You want to make sure it is smaller than 17mm to fit in the driver cavity, and short enough to not bottom out on the inside of the driver cavity. Also note, if the material will block your solder pads for the diode, you may want to attach it after the next step. I arranged mine so it left the solder pads open.

Now we are ready to solder our leads from the diode to the driver. Tin the red and black leads, add a little flux to your positive and negative solder pads, tin them, and solder them right up. Red lead goes to "D+" and black goes to "D-". Then seat your driver into the heatsink and get a few points soldered from the ground ring on the driver to the heatsink.

Now on to the host.

There is a lip that the glass reflector sits on. It blocks the heatsink from fully sitting in the head, and you will want to file that lip off. You will not need a lens for this.

That is it. Now you are ready to wrap your heatsink with some sort of thermally conductive material to get a snug fit, fit it into your host, attach the head.

Done.

Now you just need to put in two 18350 cells, and you are ready to go.

If you are worried that it is too hard to build a laser, it is not. I found it easier than a flashlight

That said, I do need to go back and address some thermal issues with mine. I need to reattach my FET heatsink, and I need to wrap my heatsink with some copper foil.

Laser guys feel free to correct me on any of this, and if I missed anything. This was my first build, so its all pretty new to me. But I am already planning on my next, either a 405nm, green or red. Not sure yet

PICS TO COME LATER

2

Nice build.
Might want to add a section on the safety issues and the need for glasses. A lot of people may not be aware of the risks.

3

Yeah I will later, but just went to bed. That's why I didn't address all thermal issues, because I just wanted to know if it all worked. I don't have any eye protection, so it will be some time before I really play with it

4

Thanks for starting this thread. I've been wanting to do a build, but didn't know which parts to use. That heatsink/adapter goes a long way towards explaining to me why that type of host is so commonly used with lasers.

5

Without glasses, be very careful indoors, there are a lot of shiny surfaces around.

6

Nice build, can’t wait for pics.

The Uvex Orange glasses are what I use, and are highly recommended for laser protection.

http://www.amazon.com/gp/aw/d/B000USRG90?pc_redir=1405595676&robot_redir=1

7

Congrats Pulsar. I just purchased a Laser Power Meter from Illumination Supply because I want to measure the output of my builds. They sell one that seems well respected at LPF for $100.

8

If I was looking at building a 405mn laser is there any reason not to save money and buy a whole used bluray R/W on eBay for ~$30-45 instead of a module someone else pulled for $60-100? Is the pre-pulled diode safer/better/worth the extra money somehow?

9

Those modules from DTR are a pretty good value. You get a tested diode that is pressed into a copper housing. The diode also has leads soldered to it (supposed to be a touchy process because heat can kill the diode). You can easily make a heatsink for it as it's tube shaped. It includes the lens of your choice and has a focusing mechanism.

You could save money purchasing the burner though. There are some other cool things in the burner that you might end up potentially using for other stuff. If you did, you would need to do the following:

  • Acquire a lens (basically a very small aspheric lens with very short focal length and AR coating for 405nm)
  • Acquire or build a lens holder that will allow you to focus the beam.
  • Acquire or build a pill to press the diode into (as opposed to a pill to put the DTR module it).
  • Learn about how to do the above so you don't ruin your diode.

I'm taking the raw diode approach to build a 3W 445nm and 1W 405nm because I want a tighter thermal path and I find the focusing mechanism on those modules a bit sloppy. But mostly because I want the challenge of building it myself.

EDIT: I don't think you can get a 16x Bluray burner for $30 to $40. Mid $50's is the best I have seen so far.

10

Is it any 16x bluray burner or are there specific brands/other spec’s I need to watch for. I’m pretty good at finding amazing deals on stuff, I would offer to make a little wager on the price I can find but I have to purchase my PIC programmer and finish up my two very high dollar light builds first so lasers are just gonna have to hold on for awhile still.

11

I'm smart enough not to wager you on that. You're looking for the burner to have the BDR-209DBK sled in it. Here is a link for just the sled on ebay.

Here is a screen shot of what the product description should look like:

This thread has good info on the diode. Sorry for all the off topic Pulsar.

12

Added some pictures to the OP. Will add some more soon

Thanks for the link Ryan. Those are pretty affordable to get a few pairs.

Most likely I will be ordering my next diode from DTR. I noticed he has a lot of modules that have the driver attached right to the diode. Wish I would have picked the m140 diode with the X-Drive attached right to it. Now I am wondering if I could do that myself since I have the X-Drive just sitting here....

13

Nice looking laser there. Is your camera auto correcting or something? That beam appears weak for the diode and current that you are running. Does the beam look like that in person?

14

No it was more intense. It looked right until the flash went off. I will try to get a few more tonight without the flash. All I have is my cell to take pics, so no matter what they will not be too good

I am thinking of getting a custom laser host to put this diode in with the X-Drive, and using this host for a less powerful diode. I am thinking the thermal properties of the p60 setup I got would be better suited to 450-600ma instead of 1.8a

Really want to build from 405nm up to 520nm and all between that are not ridiculously expensive.

15

Oh noes, you’ve been bitten by the laser bug. :bigsmile: :party:

16

I have...

Have not looked too far into it, but I am guessing 405nm, 445nm, and 520nm are all about the same price to build, and the others in that range are more exotic and expensive?

Also, looking at the diodes on DTRs site, they have an option for an extended barrel. What would be the advantage for that?

17

Do you feel the need for high mW? 100mW 405nm is cheap.
Want 520nm instead of 532? Same power for less if you go 532 with a sharper single mode dot, beam.
Green provides a more visible beam / dot for less power than blue and 405 will be much less visible.

18

What would be a cheap way to have a bright! (green or blue? ) Lazer?

I once bought a green “20mW 3v module” from lightscastle…
hooked it up with a 14500 and got a nice beam
then I turned a little bit at the trimpot and it got even nicer :wink:
until I turned too far :smiley:

19

I would prefer higher power, within reasonable price difference. I know if I go cheap and get a low powered one, I will probably want to get a higher powered one later on.

I haven't put much thought into my next one yet, just looking around at comparisons of different wavelengths getting an idea of what I would like. Got a thing for blues, so I think I would like another in the violet to teal range. But considering reds and greens.

20

From what I have seen, I'd say this build I did is about the best for the price you can do. Also from what I read though, greens will be brighter visually at lower power though.