[Michaelofburien]

Hello all,

I've got a DIY MDF/Aluminum 3 Axis Router already built. Controlling it with steppers, controllers, BOB, Mach3 and a PC. 24"x 38" x 6" working area. Its in fine working order.

What I would like to be able to do, without bouncing lasers around, is mount a laser head to the Z tram which is a 6" x 12" aluminum plate. Currently has a router mounted to it, but I purpose built it to be able to accept lots of other things. With 5 pounds of router the steppers move it around just fine and with plenty of strength so I do not think they would have a problem moving that weight in say some sort of laser diode or maybe even a tube if need be.

I would like to cut Foam block, 1/8" to 1/4" ABS sheet at a minimum and Aluminum sheet/plate if possible. Engraving might be cool too.

Ideas on a conversion like this are appreciated.

Thanks,
Michael

[inventor83]

How do you want to spend?

Any sort of "laser head" would cost thousands to do what you want. Google ND yag or dpss lasers.

Only "hobby" style that comes to mind is a Blueray burner laser. Yet you are limited to around 2 watts.

Ive been dreaming of such a device myself to no avail.

Matt

[Michaelofburien]

I'd be happy to spend under $500 but I realize that may be unrealistic.

[Exsecratio]

I'd be happy to spend under $500 but I realize that may be unrealistic.

That will leave you with diodes / c mounts and not much else Mike, an 808nm would be good (and higher powers aren't expensive) but cooling will present problems due to many diodes having a 35 degree failure temperature. A suitable driver won't be easy to find but there are quite a few guys that will custom build one for you at decent cost. You could combine two cheaper diodes with a PBS cube to get more useful power if you have the time and patience to set it all up.

cheers

Dave

[Michaelofburien]

That will leave you with diodes / c mounts and not much else Mike, an 808nm would be good (and higher powers aren't expensive) but cooling will present problems due to many diodes having a 35 degree failure temperature. A suitable driver won't be easy to find but there are quite a few guys that will custom build one for you at decent cost. You could combine two cheaper diodes with a PBS cube to get more useful power if you have the time and patience to set it all up.

cheers

Dave

Thanks for the info Dave.

So I'm thinking I have some 100W 808nm (At least I think that was the wavelength) Diodes I bought a year or so back to play with. I think I even didn't manage to burn them up. So now I need to cool them. Peltier coolers maybe? One per and maybe a heatsink. That is workable.

Where I fall down is in the driver and lens department. To be as frank as possible I have little knowledge of what would be required. I was able to power laser diodes with my cheapo adjustable power supply and keep track of it via CCD cameras and a pair of purpose bought safety glasses. But I never had lenses to expand, Collimate and focus so I just kind of found other project to move on to. With winter coming I might have the time and impetus to get this done. But I'll need help in my weak areas.

[Exsecratio]

Drivers are outside of my skillset Mike but I know some guys who will be able to help, Lensing will be fairly easy at 808nm as will expanding to get a decent spot size.

Lemme go rustle up some guys who are diode driver specialists

cheers

Dave

[Michaelofburien]

Drivers are outside of my skillset Mike but I know some guys who will be able to help, Lensing will be fairly easy at 808nm as will expanding to get a decent spot size.

Lemme go rustle up some guys who are diode driver specialists

cheers

Dave

Cool. I'll need to verify what I've got in the Diodes. But I was of the opinion that I got a pretty good deal on them at the time and they all seem to function.

[Michaelofburien]

Actually it is looking like CO2 is the way to go to get any sort of reasonable cutting Wattage without going bankrupt. Is my estimation correct?

[keebler303]

CO2 will likely be the best for cutting plastic. It will not cut or etch aluminum, though it will mark aluminum with cermark or you can mark anodized aluminum. You can maybe get kucky on ebay but even a used one is likely too expensive. Check out a Synrad 48-1 tube.

Matt

[Michaelofburien]

CO2 will likely be the best for cutting plastic. It will not cut or etch aluminum, though it will mark aluminum with cermark or you can mark anodized aluminum. You can maybe get kucky on ebay but even a used one is likely too expensive. Check out a Synrad 48-1 tube.

Matt

Too bad Synrad doesn't have a close out section. I live not far away.

Next big question is can I use Mach3 as the controller software?

[keebler303]

Too bad Synrad doesn't have a close out section. I live not far away.

I've seen some go for around $500 on ebay. Could also check laserresale.com and there are others.

[Michaelofburien]

Ok, so I'm pretty sure I do not want to afford a prebuilt laser module. So I'm thinking CO2 tube, power supply, mirrors and focusing head. As far as mirrors and lenses go are the eBay Chinese ones any good?

Power ratings for what I'm looking to do(Cut Foam block, 1/8" to 1/4" ABS sheet at a minimum, cut acrylic block and Aluminum sheet/plate if possible.)? 40W, 100W? How hard is it to weld with a laser?

[Exsecratio]

Power ratings for what I'm looking to do(Cut Foam block, 1/8" to 1/4" ABS sheet at a minimum, cut acrylic block and Aluminum sheet/plate if possible.)? 40W, 100W? How hard is it to weld with a laser?

ABS doesn't like cutting on a laser it yellows and looks aweful, Foam is fine so long as it doesn't contain any Chlorides (like PVC etc) as the fumes are highly corrosive and toxic. Aluminium is a totally different ball game, start thinking 600 watt Fiber or 1,000 watt CO2 if you want to cut metals like Ally.

Chinese mirrors are fine as are their lens's, a lower quality compared to western made but more than good enough for most things laser wise. You will also need some kind of control card to switch the beam on / off as well as control the frequency.

A cnc conversion display is on the Masters site at

http://www.cooperman.talktalk.net/

Cheers

Dave

[Michaelofburien]

Can anyone tell me about this and if it might be a candidate?

R105478 Melles Griot Gas Laser 1125P Plus Supply | eBay

[keebler303]

Can anyone tell me about this and if it might be a candidate?

R105478 Melles Griot Gas Laser 1125P Plus Supply | eBay

This is a HeNe laser with a power of 10mW. It is basically a laser pointer and will cut nothing, not even a ziploc bag.

You need a CO2 laser with 10600nm wavelength. The MINIMUM power should be 10W or so, 25 would be much better.

This is a good quality RF Laser: Synrad H48 1 SEALED Co 2 10 Watt Laser Power Supply Input 30 VDC Used Pullout | eBay

Prices start around here for an old used one and go up from there.

Lots of low budget guys are using these: 40W Water Cool SEALED CO2 Laser Tube New for Engraving ENGRAVER Cutting Machine | eBay

You need a power supply and related controls for that.

I'd really recommend some more research into laser cutting before you go wasting money.

[Michaelofburien]

Thanks for the feedback. That is kind of what I figured. Thank you again for the heads up. Looks like I'll be doing more research as you recommended and assembling a 40W.

[grawley]

You can purchase a 40 watt laser tube with power supply for your budget of $500. It can be mounted vertically and the only optic necessary is a focus lens. The 40 watt can have enough power with Cermark/Thermark (brand names) to perform laser marking on aluminum--depending upon the focus lens purchased. If you choose a smaller focal length lens then you will have a much higher power density so can attain the necessary heat to do the job. For example, you could purchase a 2.5 inch lens and a 1.5 inch lens.

There are several issues to consider with this installation. The length of the tube for a typical 40 watt sold is 700mm. With high acceleration it could risk stressing the glass to firm mounting is important. If you can forgo the aluminum marking, then smaller tubes with lower costs are available. We have a 15 watt on eBay with a power supply and the price with shipping is below 300. You could get a 30 watt that is smaller, or a 20 watt. With these lower power levels, a water pump and a plastic tank are all that is necessary to maintain an operating temperature for the laser--though if too small and the temperature varies during an engraving operation your eye will pick up the variation in laser power that occurred during the job.

Another consideration is the dust. It is typically not recommended to mount laser tubes vertically because dust can settle on the optics. However, this is more of the metal tube manufacturers making these statements, and their lasers can last many years, so it is more of a concern.

Make sure the high voltage power supply is safely protected from a laser tube that breaks (and the water comes out). Always earth-ground your laser machine with a separate line. Try to put an enclosure around the glass tube and a guide for water (we do this on our laser machines for the horizontally mounted ones), so that the flowing water will not find a path to the high voltage power supply.