First laser build. Comments? (Pics included)

Hey guys I'm new to the laser community, the last few months I've done plenty of laser research and experimenting, and took the plunge of building my own. I took notice of this community about two weeks ago read all the stickies and decided to join since there seem to be a lot of experienced people here. Anyways here is my first build and I'm just looking to see what you guys have to say about it. Thanks!

My goal with this laser was to make one with a very limited length and yet still have a decent heat capacity. And I met my overall goals with it being only 4-5/8" long.


I didn't use a specific housing, I gutted a black light flashlight that I don't use anymore. I had to grind away some metal inside so that the heatsink would fit.


I bought the diode and heatsink off ebay. The focus ring and spring are from an old red laser I had.


Sloppy I know. Used a driver I also got off of ebay that provides 1.8A. I had to gob solder on like that to make a decent connection with the aluminum and work as a heat transfer medium. I also soldered the spring on. Ugly but sturdy.



For power I'm using 3 AAA size 3.7V batteries, they don't last too long but they recharge quick and came in an inexpensive bundle.


The diode and lens came rated at 1.8W output w/ the driver I'm using, and from what I can gather this seems accurate.


Comments appreciated, thanks.

Great first build :gj:

The only thing I can comment on is this....



The was I do it is get thin copper stripping and wrap the outside of the pill with it. This 1, gives a snugger fit, 2 makes contact with the aluminum pill and 3 is easy to solder to.

The only issue with the approach you took, is if this was in a smaller build the spring can short out to the solder blobs. But it seems fine for this build. As time goes on you will pick up these little tricks and it will become easier and easier for you.

All in all, good job and keep them coming!
-Adrian

You definitely need new batteries! Not sure what kind you could fit in there though, maybe some 2s lipo pack would work good.

I highly doubt the 10440s are providing that much current. Measure the tailcap current with a DMM.

@ bobhaha
Thanks, I hadn't thought about copper stripping, the day the diode came in my world stopped until I had this built lol.

@ benmwv
The batteries are fresh and I got a 1.82A reading.

I assume he is using them in series with a linear driver... they don't last long cause you are not taking advantage of their capacity. Using a boost driver with those batteries in parallel would yield much longer battery time, even with the 10440's

They are in series I'm unaware of the difference between a linear driver and a buck driver. Care to enlighten me or point me in the right direction?

TheDukeAnumber1 said:

They are in series I'm unaware of the difference between a linear driver and a buck driver. Care to enlighten me or point me in the right direction?

Click to expand...

Linear drivers require a higher voltage than the diodes forward voltage + some for the drop out voltage for the diode. They are relatively very cheap, but they are very inefficient. For example the forward voltage of a 455 diode is ~4.5V then you need to add the drivers drop out voltage of ~1.5V so you need a minimum of 6V input to start lasing. Where as a boost driver will only need ~2V or so.

Boost drivers on the other hand boost the voltage up to the diodes forward voltage and thus does not need to get rid of the excess voltage in the form of heat, like the linear drivers do. This saves energy and gives you a longer battery life.

I'm surprised you are getting 1.8A with 10440s, especially ultrafire ones!

Cool build

Nice first build.

benmwv said:

I'm surprised you are getting 1.8A with 10440s, especially ultrafire ones!

Cool build

Click to expand...

If its any consolation, although the batteries are considered discharged at 2.5V, it loses most of its burning power at 3.2V.

Good job! Very nice for your first build :beer:

Edit: Maybe try some AW IMR batteries you should notice a huge difference in power, stability and run time. Also consider using 2 not 3 batteries as the excess potential is converted to heat and wasted with a linear driver. This will ultimately make your build run cooler...

As you asked! Heres a thread about drivers: http://laserpointerforums.com/f67/how-laser-diode-drivers-work-explanatory-thread-71513.html

its prettier than my first build was +1

Good Job... thanks for sharing. I still have my first build. What am I talking about I never get rid of any my lasers, I need to though.