A compact class 3b red

[anselm]

Hey folks!

"Water, fire, air and dirt
$%&*in' magnets, how do they work?":thinking:


So I had this targeting laser from a 15$ BB gun that broke (the gun, not the laser) a long time ago.
The laser is your crappy button cell powered, low powered red.
I noticed the size and realized that this looks promising.

Here it is gutted, all the original innards most go to make room.

To make the tip a focusing adapter, it's thread was removed.

Hey, what do you know, 12mm really IS the standard laser diameter size.
You can also see how the Aixiz lens was glued to the tip, resulting in a sort
of focussing head.

Now to my favorite part, the driver. A two-mode ("point" and "burn") driver,
an LM1117 soldered onto a 1 cent coin, a permanent 10 Ohm rsense
plus a reed switched 4.7 Ohm in parallel for a total of ~400ma burning current:evil:

Can you tell I love the looks of my driver?

Tight fit is tight. Necessary plastic sheet to prevent shorts.

No space left for batteries.

Now the sad part.
The original idea was to have it USB powered, you know, the USB accessory
no laptop should be without.:evil:
But apparently I am unable to get more than 100ma without negotiation
with the host for more power. So all the laser did upon plugging it into
the laptops usb port was blink a few times and then it stayed dark...

So as for now, I have to use one LiIon or two in a makeshift connection.
So until I figure out how to get those 5V 500mA from that USB port, or
at least make a decent exernal battery pack, this is kind of unfinished.:undecided:
But I just couldn't stand the waiting, I wanted to show off, so there you have it.
I realize the whole magnet thing is not the most practical switch, but I
really really wanted to make something original, and I had my eye on
reed switches for the longest time.

 

[jcranmer]

I like it. Tiny with power, it's a great combination. I'm a little confused though, it looks like you are controlling the power by moving the magnet? As I understand reed switches I would have thought it would be used for on / off, not power.

Hmm..As far as batteries go, maybe a small piece of PVC pipe with an ID that matches your housing? Paint it black and use it as a makeshift battery housing? I know it would make it a little bulkier but it might work, unless you can come up with a way to pull that much power from a USB port.

 

[foulmist]

Dude ... that's the ugliest driver I have ever seen :drool:

anyway nice work :beer:

 

[anselm]

I'm a little confused though, it looks like you are controlling the power by moving the magnet? As I understand reed switches I would have thought it would be used for on / off, not power.

A switch is a switch is a switch....
Hint:

a permanent 10 Ohm rsense plus a reed switched 4.7 Ohm in parallel

 

[Jimmymcjimthejim]

I did a similar build with my Micro Sized series (check the sig), where I took apart laser Airsoft modules and installed some class 3B's in them. The build is very tight, but nobody expects that much power from such a small build!