Portable Lab-Style 660nm Project! [Pictures]

[Just4FunReally]

Hello fellow laser enthusiasts! I'm working on a build at the moment to set up a LPC-826 that I've bought from Clif over here and I wanted to share it with you all for constructive critiquing and perhaps even help out the beginners in the forum.

Here is the setup I will be using:
LPC-826 Diode
LM-317 Regulator with a 2.7 Ohm resistor giving me 453mA
Key-switch rated up to 10A
Metal on/off clicky rated up to 10A
Black anodized heatsink for 12mm modules (pretty sure I got this from Clif too)
A 2x AAA battery holder
A 2.5" x 1.75" x 5.5" Aluminum Project Box host (measurements being length, height, width respectively)

So far I've tested the diode with the setup shown here:

It's just a rough setup, but I'm glad I did it before drilling into the host because the diode died on me. I was running it in 10/10 second cycles for a total of one minute at 453mA and it went zombie. Apparently Clif himself runs these at 450mA as well and they have decent lifespans, so I must have gotten unlucky with mine.

I'm planning on drilling out holes in the project box to accommodate the metal clicky which will be on the lid of the box, the key-switch which will be on the back panel, and the aperture of the laser which will be in the front. I'm also planning on screwing the black anodized heat sink into the base of the box (more drilling and some threading) for proper heat transfer.After that I'm going to properly heat shrink wrap or electrical tape everything (almost everything, as I have a very conductive aluminum host :na and fire her up. I have set it up so that all of the parts are easy to replace for future changes I plan on making to it such as adding a more powerful diode or perhaps switching to a different wavelength such as 445nm or one of the more recent direct green diodes. It's never a bad idea to do a concept run with a cheaper LPC diode before thermal epoxying your heat sinks to anything! The finished product will turn the entire host into one large heat sink that can be cooled simply by placing it on a cool surface. Also, the lab-style layout and key-switch offer a safe but still portable way to use a laser that won't roll around on a surface ( I'm looking at YOU, flashlight hosts ).

Here's some pictures of the host I'm going to use and the layout of the components once its all assembled:

And here is a picture of the resistor I'm using. It seemed strange to me that Clif could run multiple LPC-826's at 450mA to great effect and I (who is usually absurdly lucky with such things) managed to get a dud, so I'm leaving this here in case someone thinks I should switch to a 3 ohm resistor instead:

ANY AND ALL COMPLIMENTS OR CRITIQUES ARE WELCOME! Just be gentle if it's the latter of the two .

UPDATE!!!: My second LPC-826 diode has died now at a current that clif himself reccomends, so I'm either getting the short end of the stick with my diodes, or I'm doing something incorrectly. But, I did make some progress on machining the host further towards completion, so HERE ARE THE PICTURES:

This first one shows the top button installed as it would be when the laser is finished. It's slightly forward of dead center so I can always remember which way to put the lid back on if I need to take the lid off. Also, it looks better to me.

Here is the hole for the key-switch just after drilling. It needs to be filed open a little more to accept the part completely.

Filing the hole slightly wider...

Finished the hole and removed any metal burrs or sharp edges with a smaller file. Nice and smooth now .

Chose to leave the aluminum corner in and just brace the other side of the nut with some coins to keep the key-switch flat.

And the finished product from the back! I'm waiting on drilling the hole in the front for the diode until I actually get a diode that stays alive, as I want to make sure that the diode will shoot straight, and get any filing done when I actually have the laser there to work with.

:thank: for the views and or comments/assistance! I appreciate it all .

 

[kilter]

Great build and diy driver. I really like the casing. Metal :eg: +1 for you

 

[lazerphase]

Nice Build I wanna see the host and full setup when it's done! Great work

 

[Just4FunReally]

Just got my new LPC-825. Gotta +1 clif when I can, the diode pressed into a copper module with leads attached without me asking , makes life easy for us. The diode fired up and after testing it on some matches at 10ft it is definitely the good ol' single mode I remember. I've been using my 445nm diode for so long, I forgot how beautiful single mode reds are . I'm going to drive over to my grandpa's place tomorrow, he's got a much larger array of drill bits than I, and I don't have all of the equipment to do this properly myself. ALL HAIL: OLD DUDES RULE.

Thanks for the kind words Kitler and Laserphase. Like I said in the first post, I'm probably going to swap it out for something more powerful/unique later. Maybe using Clif's dual wavelength diode . I'd just have to add in a on/off/on switch and switch out the resistor.

 

[Cyparagon]

Are you going to run into problems with the case-potential of the regulator and laser diode?
Your diode heat sink is case negative, and your regulator heat sink is at out potential... and your case-case is metal.
Might end up shorting something. Be aware.

 

[Just4FunReally]

Are you going to run into problems with the case-potential of the regulator and laser diode?
Your diode heat sink is case negative, and your regulator heat sink is at out potential... and your case-case is metal.
Might end up shorting something. Be aware.

This is something that I am well aware of, and I'm glad that you could point it out because I forgot to mention it in my first post. I'm going to encase the driver in electrical tape and then shrink-wrap it. Also, all of the solder joints will be shrink-wrapped or covered with electrical tape. Again, thank you for the concern, I'm glad to have you helping out .

On a side note, my SECOND LPC-826 has died now. I double checked the current the first time, and triple checked it the second time; the driver is running 453mA to the diode, they run fine for a couple of seconds before going zombie and then dying. On the page where Clif has them for sale, he says that he has several running at this current and they are healthy and alive, but twice now mine have died. I'm going to ask him what might be wrong, but if anyone here as a solution, please feel free to share. There's no possibility of it having shorted somewhere, because I have only tested it outside of the aluminum box so far. Like I said: I want it to work before I actually work on semi-permanent assembly.

 

[Cyparagon]

Oscillations could be killing them. I don't see a filter cap anywhere. Add a small capacitor in parallel with the laser diode.

Electrical tape will indeed electrically insulate the regulator, but it will also thermally insulate it. Bolt it to the case instead using a nylon washer and insulator pad. This will insulate it while still keeping it cool.

 

[Just4FunReally]

Oscillations could be killing them. I don't see a filter cap anywhere. Add a small capacitor in parallel with the laser diode.

Electrical tape will indeed electrically insulate the regulator, but it will also thermally insulate it. Bolt it to the case instead using a nylon washer and insulator pad. This will insulate it while still keeping it cool.

Thanks a bunch! I will take your advice, but it seems strange to me that they both died under very similar circumstances, and I've never had such issues before with the LM-317 oscillation on my old LPC-815 build, nor any of my PHR-805 builds. I always assumed that the regulators were sufficient and that the cap was just excess as a fail-safe. Thanks again for the comment, I read the DIY driver thread a while back but totally forgot that the cap could be added for extra safety . I'll +1 you when I can.

 

[grainde]

Nice build! :gj:

Just thought Id mention though, that the coins you used to hold the key switch in place could easily get dislodged if you knocked the box. If you haven't already, it might be an idea to super glue them in place. If they do get dislodged you could end up shorting something... :beer:

 

[Just4FunReally]

Nice build! :gj:

Just thought Id mention though, that the coins you used to hold the key switch in place could easily get dislodged if you knocked the box. If you haven't already, it might be an idea to super glue them in place. If they do get dislodged you could end up shorting something... :beer:

Ah, i epoxied them in place, and also electrical taped the ends of it so that if it somehow dislodges anyway, it wont make metal-to-metal contact with the case. Thank you for the concern, but I've already got a massive first post so I didn't want to clutter it up more with extra text .

UPDATE: I'm actually just an idiot. I ordered a different diode and forgot to set the driver to a different current for it. Sometimes double checking doesn't help if you're just plain retarded.