3W in a small box

OK, I admit it, the primary reason I built this laser was to see just how small I could make a host, and still have good power output. With that in mind, I started looking for small batteries with high power output, and decided that one good choice would be Li-Ion camera batteries. As with my first build, I chose to machine my host from a solid block of 6061 Aluminum stock. As can be seen in this first picture, the final host build is nearly the same size as the little metal mints box; actual measuments are: 3" x 1.5" x 0.75" (76.2 x 38 x 19 mm).

The top of the host has two switchs (for safety); the aluminum slide switch on the far right doubles as a battery power switch and a shutter, while the little red push button momemtary is the primary on-off.


The following two pics show the front of the host. The first pic shows the shutter closed, and second pic shows the shutter open. Since my planned use calls for me to carry the host around in a pocket, I wanted the shutter as a failsafe way to block the laser from first burning a hole into a pocket and then moving quickly into my flesh.
I started out with a drilled round hole in the shutter cover plate, but noticed that my beam was actualy much wider and flatter than I thought it would be, so I milled out a slot to accommodate the shape of the beam.



Removing a single 2-56 screw allows the cover to be removed, providing access to the batteries and all the other components. I mounted the X-drive board in the top left corner of the box, where the design wedges the main IC chip tightly against the side of the alumunium box which acts as a large heat sink.


With the two batteries removed you can see how the electrical conections to the batteries are made using "pogo pins" (salvaged from an old battery charger I no longer used). A good deal of machining effort went into fabricating the white plastic block (made of Delrin) which holds the pogo pins, both switches & the X-drive board. The plastic block is machined to be a snug fit into the aluminium box and once the lid is screwed into place, it's held firmly in place without the need of any additional screws.


Below is a view of the front of the white plastic block; the two parallel wires on the front of the block are short sections from a paper clip and act as the electrical contacts for the slide switch which is lying outside the box to the far right. The LD assembly is held in place with a single 4-40 set screw. I purchase the LD-Lens-Driver assembly (G-2-LFL) from DTR which simply worked great right out of the box.


The two pics below show how one of the paper-clip terminals is bent up and is soldered to the negative side pogo pin for the top battery.




Finally, here it is in operation.


I will attempt to anodize the aluminum parts in the near future, but I haven't quite perfected my technique yet...so for now, I hope you enjoy this unique design in it's bare aluminum appearance.

Holy Crap this is very impressive! This must be a 9mm diode. is there enough heatsinking? if so this is very cool. It is an especially interesting form factor it must have been dificult to fit it all in there. I bet you have great tools at your disposal.

Man I wish I had access to a mill or cnc machine. That is really professional looking.

I see more pics were added. I too was concerned about the heatsinking, pretty sweet though

Nice job wizard!
I can really appreciate all the time and effort that you put into designing and machining that host and switch holder/ batt. Contact block.
That thing isn't much larger than an old "zippo" lighter, but it's so much cooler.

BTW - What color anodizing are you looking at?

+1 for some innovative work!

Very nicely done! +1

Awesome!' I like these innovative builds! +2

Thank you all for the compliments,.. they are most appreciated:thanks:

LaserSam & Speedy78, I did all the milling on a Grizzly G0708 manual milling machine which I had purchased a few years ago. These are great mills for hobby or production work and sell new for about $1100.00. Of course the mill is just the begining, as you will also need a clamp set, collets, vise, and milling bits. I also used a few hand tools such as hack-saw, dial caliper, hand tap, & files.

I only completed the build a few days ago and have only had it turned on for perhaps 20 or 30 seconds continously at any one time; the areas around the LD and the X-drive do get noticeably warm, but no warmer than the water you might wash your hands in. How long would you suggest I leave it in an on condition continously as a good test??

As for what color to anodize it,...I'm open to several colors, I realy like the blues, golds, and reds I've seen on many of the flashlights available today. I will try to anodize the shutter with a Type III (hard coat) black; adding a hard coat will greatly add to the wear resistance on the sliding surfaces of that specific part, and a hard coat is also a great electrical insulator which isn't a "must have" but is a "nice to have" on that part.

LaserSam said:

Holy Crap this is very impressive! This must be a 9mm diode. is there enough heatsinking? if so this is very cool. It is an especially interesting form factor it must have been dificult to fit it all in there. I bet you have great tools at your disposal.

Click to expand...

I just ran the following test:
Starting with both batteries fully charged and the unit at room temperature (73.5F), I held the momentary switch closed, operating the LD continuously. At one minute, only the front one fourth of the box is slightly warm. At two minutes, I can feel the entire box getting warmer, not hot, or even uncomfortable, just a pleasant warm. At three minutes, the front end of the aluminum box is so warm that I don't want to continue the test; it was not so hot as to burn my hand, but hot enough as to be unpleasant to hold tightly enough to keep the momentary switch pressed on. I don't own a Laser Power Meter so during the entire test I panned the laser over small pieces of wood and watched for the small puffs of smoke that let me know that the beam was still plenty hot throughout the 3 minute test run.

For my planned use I cannot image a time when I would want or need to keep the laser turned on for more than 30 seconds continuously, so I'm more than happy with it's heat dissipation abilities. If you need to operate your laser for longer than 3 minutes, while holding the host, than I would not recomend this design.

That sure looks awesome. normally, box-type builds just look a bit crap...But this is just nice and clean, compact. Good work, +1