CO2 laser build (from scratch)

[Kratos]

I am planning to build a CO2 laser from scratch (literally producing the gas and filling the tube etc...) and wanted to ask about what to use for the inner tube (the one with CO2 in it) in terms of materials, what kind of optics setup to use, and what to do for the power supply (i.e. voltages needed, materials to use for electrodes etc.).

I am aware that it would probably be easier, cheaper, and quicker to just buy a prebuilt one, but I enjoy building things, and have just always wanted to make a gas laser.

 

[RedCowboy]

There are several people on Y-tube who have done it, I am just going to buy a tube or cavity, but there's good detailed build videos, just search it.

 

[Kratos]

Thanks.

 

[RedCowboy]

I am planning to use a ZVS and flyback driven by a simple e-bay DC to DC converter, coolant pump and radiator are a must I'm sure you know.

 

[diachi]

https://www.repairfaq.org/sam/lasercc2.htm

 

[FRITZ HID]

have you ever built a laser before?
most CO2 lasers in the lower powers are made from HQ glass, water cooled and very precise in the beam path. do you have any glass working exp?
some CO2 use RF power others use HV, do you know how to safely work with either of these?
vacuum pumps and seals must be precise as well.
you sure you want to jump right into building from scratch, a gas laser?

 

[Kratos]

>have you ever built a laser before?
No, but I have a laser, and have worked with electronics/circuits before.
>most CO2 lasers in the lower powers are made from HQ glass, water cooled and very precise in the beam path. do you have any glass working exp?
No.
>some CO2 use RF power others use HV, do you know how to safely work with either of these?
I know how to work with HV, but not RF
>vacuum pumps and seals must be precise as well.
I have some experience metalworking, and I'm not aiming for it to be pretty, so I can use some silicone to get a good seal on the vacuum tube.


Right now I'm looking into where I can source the mirrors from, the HR is pretty easy, but do you have any recommendations for the OR.

Thanks.

 

[CurtisOliver]

Good luck Kratos. Very ambitious and I have respect for you wanting to try. You want to look for CO2 output couplers. Stay safe! :beer:

 

[Laserbuilder]

Right now I'm looking into where I can source the mirrors from, the HR is pretty easy, but do you have any recommendations for the OR.

For the first time you can try a copper plate with the 2-2.5 mm dia hole in its center. The hole must be sealed with a small shard of ZnSe or a piece of polished NaCl ordinary salt crystal. Try visiting Jarrod Kinsey's web site, he has a rich experience building CO2 lasers. Jarrod's Laser World: First CO2 Laser

Good luck!

 

[diachi]

For the first time you can try a copper plate with the 2-2.5 mm dia hole in its center. The hole must be sealed with a small shard of ZnSe or a piece of polished NaCl ordinary salt crystal. Try visiting Jarrod Kinsey's web site, he has a rich experience building CO2 lasers. Jarrod's Laser World: First CO2 Laser

Good luck!

Yeah, any windows need to be ZnSe or NaCl, regular glass will not work. Regular old glass is opaque at 10.6um.

 

[paul1598419]

With the limited experience you have, I'd research all sources before even starting as failure can come quickly with the lack of any small piece of necessary knowledge. I wouldn't buy anything until I was very confident that this is doable to you, and know all the pitfalls ahead of time.

 

[Laserbuilder]

I'd research all sources before even starting as failure can come quickly I wouldn't buy anything until I was very confident that this is doable to you, and know all the pitfalls ahead of time.

When I was building my CVL -- I had no experience at all with high voltage electronics of short nanosecond pulses. Moreover, there was no hobbyists' experience on CVL published in the internet too. I read loads of literature and scientfic articles about CVL power units. But such research gives only a direction for your own RnD. It doesn't give a FULL COMPLETE guide and does not insure you from failure. The point is that scientists write their articles for other scientists, not for hobbyists, so they allow themselves to omit some small but very important details when describing their laser projects, because they think that these omitted things are obvious for other scientists. For example, nobody give a clear explanation how to develop a good and stable Blumlein generator with the hydrogen thyratron. They only reported "We took this HV transformer, that thyratron and a bunch of those unobtainium capacitors, threw it all together and it worked well".

So, I would refer to hobbyists' articles, like Jarrod's one. Anyway the full experience can be got only during experiments. So find a more or less detailed guide and try to repeat, rebuild the project described in it. During your experiments you'll find out quickly how it works and don't be afraid of fails.

 

[paul1598419]

When I was building my CVL -- I had no experience at all with high voltage electronics of short nanosecond pulses. Moreover, there was no hobbyists' experience on CVL published in the internet too. I read loads of literature and scientfic articles about CVL power units. But such research gives only a direction for your own RnD. It doesn't give a FULL COMPLETE guide and does not insure you from failure. The point is that scientists write their articles for other scientists, not for hobbyists, so they allow themselves to omit some small but very important details when describing their laser projects, because they think that these omitted things are obvious for other scientists. For example, nobody give a clear explanation how to develop a good and stable Blumlein generator with the hydrogen thyratron. They only reported "We took this HV transformer, that thyratron and a bunch of those unobtainium capacitors, threw it all together and it worked well".

So, I would refer to hobbyists' articles, like Jarrod's one. Anyway the full experience can be got only during experiments. So find a more or less detailed guide and try to repeat, rebuild the project described in it. During your experiments you'll find out quickly how it works and don't be afraid of fails.

I believe you misunderstood my comments. I didn't say to limit one's research to scientific papers, but it was my intent that anyone attempting this look at all types of references, including those from people who have accomplished what you are attempting. Often it is the successful DIY resources that can be of the most help. I believe in this way one can limit the number of failures on a project and therefore limit $$ and time. This is, after all, a CO2 laser and there are plenty of resources available on them.

 

[FRITZ HID]

you can also look on eBay for CO2 Laser Processor components, they'll be used but cheaper. if i still worked in the field, i could prob find you some used ZnSe OC and bounce mirrors. they'd still lase but just not well enough for a clean cutting beam.
Keep in mind that these HV tubes can act as capacitors so just because it's off/disconnected from the PSU, they can still pack a punch. the RF tubes can be even more dangerous because they don't even need contact to mess you up.
if you're planning a pulsed laser, you may get away without needing cooling but any CW use will.

GL with your project! Stay Safe!

 

[RedCowboy]

Why not just buy a tube and build your own power supply and cooling system, as well as a user interface such as a pair of handles that grip the tube with controls or an enclosure with controls, or do you just want to build one for the fun of doing it?

If you want a cutter you really can't compete price wise with China, their desktop USB ready to use cutter/engravers are very affordable.

I may show off a build with a purchased commercial tube, heyyyy hows about a double barrel side by side pair of tubes....I wonder haw far apart they would have to be?

I wonder could 2 identical tubes be powered in series or parallel ?

Any imbalance between them could be a real problem, I wonder has anyone done it yet?

New Chinese tubes can be had for not much more than 100 dollars.

 

[Anthony P]

Are you still working on this project. I have done several scratch built CO2 and may be able to help. Among home-built lasers the CO2 is remarkably forgiving. Even with a leaky vacuum system and poorly aligned mirrors it is easy to get substantial output. Feel free to contact me in this forum or use that "conversation" thingy.
In response to RedC I don't thing 2 sealed tubes would be feasible, but a folded resonator is not out of the question for home-built.