WTB: 3 watt - 5 watt laser diode/completed module

[lostinspacebar]

Hi,

I am looking to find a laser diode or module in the 3-5watt range. A finished module with power supply and such would be nice, but maybe even a diode with a good set of specs/details would be ok.

I am basically trying to cut plastic (acrylic or ABS around 1/8th - 1/4th inch thick panels). I am not looking for any specific wavelength right now.

I've seen stuff like 5000mW 808nm Laser Infrared Flashlight , but I've read in places on this forum that that site has a tendency to basically lie about the output power (stating input draw as output power).

Thanks,
Aditya

 

[rhd]

Since that site shows a green beam coming from an Infrared laser, I'd be worried right off the bat

Are you looking for portability?

 

[JLSE]

(5000mW)
Operating Current (mA) : 900ma

Not possible.. At 900mA you will be lucky to see 1W, let alone 5.

I have 10W bar LD's and all the optics to suit your application..

Only thing is, at 808nm the material to be cut would have to
be dark in color...

 

[rhd]

Even at 10W you'd need it to be dark in colour ?

I had no idea the wavelength had that much impact (to the point of 10W no cutting white etc)

 

[lostinspacebar]

@rhd: Portability is not really a concern. If it wasn't apparent already, I am trying to make a laser cutter. So if the actual laser module part is maybe the size of say like (5" x 5" x 6-8") I think I could probably deal with that. Anything smaller is better. The power brick/regulator/driver can be w/e. This will be a bench top thing.

@wannaburn: 10W seems like.. a LOT. How expensive would that be? I am looking for something in the range of maybe 200-400 dollars if that's possible for 3-5W. I can probably work with only using darker colors.

Thanks,
Adutya

 

[Bionic-Badger]

Hold up a sheet of acrylic. Can you see through it? Then any laser light of a wavelength that you can see through the acrylic is not going to be absorbed by the acrylic.

You need to use lasers that are suited for your task, and for cutting acrylic, that means a CO2 laser, which is 100% absorbed by acrylic. Anything else is going to pass through that acrylic without much ado. Even 808nm goes straight through acrylic as well, so near-IR will not work either.

 

[lostinspacebar]

If had a red laser and blue acrylic, wouldn't the acrylic absorb most of the light coming in? Or is the power still not enough?

C02 seems prohibitively expensive

 

[JLSE]

Granted the material is dark... I think 3-5W would be too low for 1/4' material
as stated in the OP.

I can make up to 60W with what I have in hand, but you will have to
figure out the requirements for the thickness indicated.

As Bionic-Badger mentioned, the simplest solution would probably be a CO2.

They are likely to be more in your price range for a complete system.

 

[Helios]

If had a red laser and blue acrylic, wouldn't the acrylic absorb most of the light coming in? Or is the power still not enough?

C02 seems prohibitively expensive

CO2 is about the cheapest per watt laser system there is!

I think smaller tubes and matched power supplies can be had for under
$400 but you I tend to only see them in the 20-100W range which is more expensive.

 

[lostinspacebar]

Yeah, I am looking online for "c02 lasers" and all I see are 30W and up and they are in the $2K-10K range... which... not so great for me lol

Guess I'll search more since I know they DO exist. What could I expect for $400? 3-5W? Maybe?

 

[JLSE]

Not sure of the output, but ive seen these from another seller
who doesnt sell underspec..

Focusable 4.0W 808nm 810nm Infrared Laser Diode Module | eBay

Not sure how the focus is etc.. You could always contact them and see..

 

[lostinspacebar]

I am trying to read up on C02 lasers, but so far I can't find stuff about why they would produce a laser beam that's absorbed by acrylic when something out of a diode wouldn't. At the end, it's just light is it not?

@wannaburn: That seems like a good one. Might have to settle for the $500 if I can't find anything else. Thanks. More ebay hunting is in order I guess.

 

[Helios]

Ive read great things about these ebay CO2 lasers

40W CO2 Laser Tube + Power Supply Cutting Engraving | eBay

and its $388 buy it now WITH shipping...and its 40W! :beer:

Looks like the parts might be even cheaper purchased separately for some reason. If you want it to cut a fine point you will need special optics but they can be had on ebay as well.

You would need to cool it but many people are successful using a simple aquarium pump and a regular automotive heat exchanger. Especially if your running it at lower power. Plus it will cut acrylic like butter with a samurai sword on the hottest day in June.

 

[Bionic-Badger]

If had a red laser and blue acrylic, wouldn't the acrylic absorb most of the light coming in? Or is the power still not enough?

You're not seriously going to limit yourself to dark blue acrylic are you? The cost of that and the impracticality of selling products made from only blue acrylic would probably negate any savings you'd make from avoiding the proper laser.

C02 seems prohibitively expensive

Not when you consider how efficient and powerful it is. $2000 for a 30W laser? You won't find that kind of power in any visible light laser even approaching that price. Nor will you see 100% light absorption.

I am trying to read up on C02 lasers, but so far I can't find stuff about why they would produce a laser beam that's absorbed by acrylic when something out of a diode wouldn't. At the end, it's just light is it not?

Light is just light the same as radio waves and visible light are both just "light." You need to use the proper wavelength of light for your application. The only reason visible-light lasers burn anything is because the light is absorbed by the material and that causes it to heat up. That's why when people burn things with their lasers, it's usually some mundane object that is colored black with a marker, or something that is already black like electrical tape or black balloons. Laser burning by hobbiests is really pretty darn lame.

CO2 lasers emit light in the 10um range, whereas these visible-light diode lasers (which can also include 808nm) emit light in the < 1um (1000nm) range. The 10um range is in the far-infrared which is considered radiant heat. Acrylic is opaque to that wavelength and this allows the laser to vaporize it as energy is efficiently transferred to the material.

Something else you can consider: use cutter or hot wire/knife and do the cutting. Why use a laser when something else will suffice?

 

[lostinspacebar]

@Bionic-Badger: I am not really in the laser cutting business. Myself a few other friends do a lot of robotics work and we would love to be able to cut out plastic for enclosures or parts. So color is really a non-issue. Even material is a mostly a non-issue as long as it's rigid and acrylic-ish(so ABS or plexi would be just as good).

With that in mind, $2K is kind of a lot. Considering the rest of the machine will probably cost another 200-300 dollars to make. We are looking at laser cutters because it seemed the easiest when it comes to control and ease of use.

Thanks a lot for the insight so far though. The info about the 1um range is a nice tidbit I can search more on!

 

[Bionic-Badger]

Yeah, it's a bit more complicated than that. Perhaps you should look into 3D printing services like Ponoko to have your designs fabricated. Then if you make money from whatever you create you can buy a machine yourself.

Another thing to try is to just get an inexpensive CNC machine and just use a drill/router or something else mechanical. Laser cutting really isn't all it cracks up to be unless you have all the proper equipment for it. Ironically, the laser is often the simplest and cheapest part of the entire apparatus.