Successful DIY CO2 laser, made from scratch!

It was Saturday night, on July 3rd 2010. My room was filled with the glow of a large red pilot lamp. Just outside, I could hear the thumping sound of a nearby firework display, celebrating the upcoming 4th of July. However, I was celebrating with some fireworks of my own - fireworks of different kind. At around 8:30pm, my first CO2 laser was born! I saw a puff of smoke as a small hole was burned into a paper target placed in front of the laser.

Here are some videos of the laser in action:

YouTube - CO2 laser made entirely from scratch!

YouTube - Melting a rock with my new home made CO2 laser

YouTube - Home Made Baking Soda Laser With Improved Performance

Here is a set containing some detailed photos (including some of the stages during construction). I will change the set as I collect additional photos.

CO2 5-10 - a set on Flickr

There are some problems with this design. The tube is too long, and the clear plastic water jacket is too flexible. At only 15kV, this long tube requires tight seals, a good vacuum, and a lot of helium. It is also extremely hard to align. The flexible water jacket becomes pinched along it's length, becoming oval shaped instead of round, as pressure is reduced while siphoning. As I write this, the epoxy is curing on a new tube that I am working on. Even if I have to sacrifice output power, this smaller tube might be a worthwhile tradeoff over the problems encountered with the longer one.

Update: I finally coaxed the big laser back up. I aligned the HR with the vacuum pump on. This enabled me to compensate for distortions that occur when the tube is reduced in pressure.





Here's the unsightly demise of a lamp's outer glass housing ...

http://farm5.static.flickr.com/4075/4788526169_97e1daeaf7_b.jpg

Here's another view of the focused laser beam, 'beating up' on a target ...



Artist's charcoal (with focused beam)...



Please continue to check back with my Flickr set for updates. As I do new things, or as I just make new pictures, I will continue to add, amend, and edit the content in the existing set (just click on my Flickr-set URL, which is inserted below my Youtube video URLs above).


Jarrod

wow very very nice. love the pulsing tube

Excellent work, making a working scratch-built gas laser is not an easy task

Thanks!

The pulsing (or obvious drop in power after start up) is not surprising. An efficient cooling scheme must be devised in order to avoid this. Either flast flowing water (through the cooling jacket) or faster flowing gas would help here. But I was just glad to get a beam! This is all brand new for me.

Fascinating! You have my respect, sir.

That is freaking awesome.

So are the mirrors themselves (and correlating o-rings) the end seals for the plasma tube?

Very very very cool. I think I might give this a shot. Where did you pick up the glass and the optics?

Cyparagon said:

Fascinating! You have my respect, sir.

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Thanks! Now If I can just get my smaller one up and running. I'm working on it right now.

GooeyGus said:

That is freaking awesome.

So are the mirrors themselves (and correlating o-rings) the end seals for the plasma tube?

Yes they are.

Very very very cool. I think I might give this a shot. Where did you pick up the glass and the optics?

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Someone donated both. I recommend Ebay as a source for the optics. If the ZnSe cannot be located, then here is the next best thing for a truly DIY-scratch approach from before ZnSe optics existed (I plan to experiment with copper mirrors and salt windows in the future) ...

The Amateur Scientist

MarioMaster said:

Excellent work, making a working scratch-built gas laser is not an easy task

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I've done nitrogen, nitrogen pumped dye, and ruby. A lot of folks are in love with visible beams. However, I'm more interested in high performance lasers that can be made from scratch.

Jarrod has built a laser as I did for my first one 35 years ago. This is no small task and he has innovated well.
Don't bother with copper and salt unless you have to. It's a PITA. If you want salt, I'll send an unpolished crystal window as I used long ago.

HMike

CO2 lasers are amazing. They are simple, yet complicated. They just have a aura of sophistication to them.

Thats just my opinion though, I love all gas lasers
You just reminded me of the 40W tube I have sitting here, I need to finish my PSU for it...

simply amazing!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Hemlock_Mike said:

Jarrod has built a laser as I did for my first one 35 years ago. This is no small task and he has innovated well.
Don't bother with copper and salt unless you have to. It's a PITA. If you want salt, I'll send an unpolished crystal window as I used long ago.

HMike

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Mike,

If you have an unpolished salt crystal, then yes; I would love to have it. I plan to do experiments with different designs in the future. My goal is to see how 'little' I can get away with. I like to try different things in an effort to determine what will work, and if so, how well. I like to take note of the advantages and disadvantages of different approaches. In other words, I like to just go crazy with trial and error experiments.

Right now, I cannot get my laser going again. I'm not sure why. I eventually need to get a real gas mix. Any idea "how" I can obtain some, for a good price. Forget Ebay. The shipping would be too much. I need an approach that utilizes local suppliers. I just need to know where to go, and what type of suppliers to look for. I'm not looking for big laser supply companies. They will be too expensive. They aren't interested in what I am doing anyway - big companies sell large volumes of gas to people who buy thousands of dollars-worth at a time. I won't somebody who is willing to help out an amateur on a budget.

I'm working on a new tube. This will be shorter (only about 18" arc length), and should be easier to align.





This bad boy is almost identical to the first, except it is made entirely out of fluorescent lamp tubing.

Pontiacg5 said:

CO2 lasers are amazing.

I agree!

They are simple, yet complicated.

Just like the so called "Influence Machines": simple steampunk mechanical devices by eye, with complex processes taking place beyond the eye level. There's often a lot of theory behind simple devices - physics. That's what I like! Pure science as opposed to high-tech complexity.

They just have a aura of sophistication to them.

I like a laser that you can build from scratch. I like macroscopic lasers. Diode lasers can probably be fun to play with, but I like something I can build from the ground up.

Thats just my opinion though, I love all gas lasers

Yes. Old lasers are more interesting to me. Constructing the device can be an art form. HeNe's and Ion lasers will probably be replaced with diode-based products, eventually. But it's probalby going to be a long time before they make a diode-based device that can perform like a CO2 laser.

You just reminded me of the 40W tube I have sitting here, I need to finish my PSU for it...

Click to expand...

PSU? Tell me more about this!

Thanks

Arayan said:

simply amazing!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Click to expand...

Thanks!

jarrod694 said:

PSU? Tell me more about this!

Thanks

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My first successful PSU consisted of 2 CRT monitor flyback transformers in parallel, and it worked but was not anywhere near as efficient as it could be.

For my next supply I intend to use a Cockcroft–Walton generator off of a neon sign transformer with a ballast resistor to limit the voltage and current to keep the tube alive longer. Either that or a matched neon sign transformer and an automotive coil for "starting" the tube.

But that has been long forgotton behind all this new 445 craze. And will probably be completely forgotten when I get my argon