40W CO2 laser engraver & cutter - US source - $529 shipped

Anyone have any experience with one of these? 381 sold from this US supplier:

https://www.ebay.com/itm/40W-CO2-LA...590?pt=LH_DefaultDomain_0&hash=item2a13213436

An operation video of a cheap Chinese 40W CO2 laser of unknown type (since the guy never showed the actual unit or provided an eBay seller ID or link!) doing a great job with what looks to be 3-ply "wood veneer" as this guy called it. It looks and sounds like 3/16 or thicker plywood when he handles and drops it:

[video=youtube;7evBpkTLxNQ]https://www.youtube.com/watch?v=7evBpkTLxNQ[/video]

I'm impressed. The only question I have is what is the replacement cost of the laser tube, not that it's a big deal as the entire cost of the machine is less than the cost of the laser tube in a brand name laser cutter..... And in 1000 hours you can cut a lot of wood.

A CO2 laser cutter will cut wood and paper. It will not cut any metals as they are reflective and have good thermal conductivity, CF composite, and most likely not cut FG composites. It will cut Plexiglas but may not cut all plastics.

It looks like a reasonable machine for low volume hobby rocketry kit making.

Bob

CO2 laser cutters work extremely well for cutting fabric. It makes a lovely thin fused edge on sheets of fiberglass that prevents fraying, and it has unparalleled precision for cutting Kevlar.

For preparing fabric pieces for tip-to-tip, nothing can compete.

I'm beginning to wonder about this Chinese stuff. I have had several low cost electrical items fail after little or no use.

I researched this and have been hesitant to order.

cwbullet said:

I research this and have been hesitant to order.

Click to expand...

I researched what looked on the outside to be the same sort of machine a few years ago and read reviews, but this looks like an improved version addressing previous complaints, one of them I recall being smoke venting which isn't even mentioned in the broken English text I include below that caught my attention in the eBay ad, but which has apparently been addressed with the external fan and vent tube shown in that ad:

Updated HIGH PRECISE and HIGH SPEED Third Generation CO2 laser engraving, cutting, USB PORT

FDA Compliant, CE Certification, ISO9001 Quality Certification

USB Port to Computer (earlier versions I researched used LPT)

More Precise Stepping Motor

Reinforced and thickened machine body make transportation absolutely to be safer and longer life time

Built heat dispersed fan to reduce all electronic component's temperature

Adopt Japan imported advanced motherboard and microchip to make engraving high speed, high accuracy,and machine long-life.

Adopt Germany imported bearing and high accuracy stepping belt which not only make the engraving more precise, also make the machine life time twice to three times than ordinary CO2 LASER Engraver

SHIP from USA, DUTY FREE

DHL or FEDEX with TRACKING NUMBER

Doing some looking on-line and it appears these were over $800 only two years ago. A few good threads I've found:

https://www.cnczone.com/forums/gene...32-40-watt-dc-kiii-laser-finally-arrived.html

https://www.cnczone.com/forums/gene.../138554-cheap-laser-cutter-modifications.html

https://www.buildlog.net/forum/viewtopic.php?f=16&t=909

EDIT: a comment found here https://www.cnczone.com/forums/gene...ion/151415-grounding-dc-kiii.html#post1113159

"I have this laser and i routinely cut 3mm material and on sometimes 6mm. Mostly acrylic or wood."

6mm is only a .015" short of 1/4".

I'de love to own something like that and learn how to use it. Watching that Video makes me want one, but it's way out of my Budget.
Sameday...

Someone offered to give me a 20 year old laser cutter that they used to use at their old job. An "engraver" type laser that he used for various rocket parts, on the side as he used it at work. The laser died. The quandary is a "free" laser cutter, but that the replacement laser for it costs about $1000, if the maker still sells old lasers to support the old machine.

So, I've been daydreaming about a "new" laser like the ones form China. The replacement laser itself is about $100. If I was really good at tinkering with machinery, in theory it might be possible to even mount the $100 laser onto the old "free" machine. But I'm not a good machine tinkerer.

One of he drawbacks ot me of any of the cheap ones, and evn a bit of an issue with others, is the software. The cheap chinese lasers use some sort of drawing software that seems like a real PITA to use, many users complain about it. I have seen a few that use CorelDraw. Although I do not use CorelDraw either, but it would be better to use something more common.

The best situation would be laser cutters that can be used like a "printer". So that one could use any kind of graphics or drawing software, and the laser could be adjusted to "print" at whatever laser intensity to do the desired effect, whether etching into wood to produce plaques, or to cut actual parts. Actually the old laser cutter my friend used has a manual capability to set the laser for an exact intensity for the job. He could adjust the laser power so fine as to be able to take a sheet of black decal paper (water transfer type), and the laser would burn thru the black decal but leave the paper uncut. So, the laser cut out perfect lettering for scale models. The cheapest chinese lasers seem to to have a crude means for setting the laser intensity ( a knob turning a potentiometer, the worst being that the laser intensity setting was displayed using a crude analog ammeter (rotating needle against a printed numbered background), instead of a precise digital readout). Ironically in some ways, the hardware cost for a digital display and simple up-down buttons to vary the intensity might not cost more than an ammeter and potentiometer (but it would require some software code changes in the controller board). Now actually I think that one of the cheap but not cheapest cutter DOES have a digital display and adjustment, but the apparent knockoff clones of that one use the ammeter/potentiometer method.

Anyway…. it is looking like the cost of the hardware is getting closer to being more practical. And inevitably someone is going to marry the cheap hardware with better software to make them far more practical to use.

And I sure hope that inevitably someone writes up good useful manual, not something in sketchy "Chinglish" or Google translated.

Actually when I was web-surfing a few months ago, I ran across someone who was making up a $100 driver board to replace the one in the Chinese laser cutters. IIRC the goal was to make it work like a "printer", so it could indeed use a wide variety of common graphics software, in place of being forced to use specific software. I might not be enough of a tinkerer to be able to work out how to bolt a new $100 laser into a 20-year old laser cutter not designed for it, but I think I could handle swapping out the control board (since the project is aimed at being reasonable to swap the original board with the new board).

I have a lot of other stuff to do for the next few months. Even if a laser cutter showed up tomorrow, I would not have time to learn to use it, it'd have to sit till September. But after things slow down, I'm going to take another look at what's available, at what price, and most important, how practical it would be to use it.

Now, I cannot personally afford it anyway. But, a friend is interested in having the capability, if I could draw up and cut the parts that he needed, and I'd get to be able to cut stuff for my own uses too. Maybe even offer some specialty items for sale.

I also daydream of some sort of 3D printer. But I have no experience with 3D software. I'm going to take a look at 3D software too next fall, see if there's something I can learn reasonably.

- George Gassaway

Whaaaa??? You can't read Chinglish yet?

georgegassaway said:

And I sure hope that inevitably someone writes up good useful manual, not something in sketchy "Chinglish" or Google translated.


- George Gassaway

Click to expand...

Zonie said:

Whaaaa??? You can't read Chinglish yet?

Click to expand...

Oh, I have been quite entertained by some "manuals", or as the case may be 1-2 pieces of paper "instructions" for some devices. There was a made-in-China electric sailplane that had howlingly bad words and phrases in it's manual. Wish I had it handy to type in a couple of examples.

But at least in those cases they involved something I already knew the basics for, and could figure out most of what it meant....and figure out the rest without it (Look for some sketch indicating where to locate the Center of Gravity). The engineering of that particular electric sailplane was plain crap.... there is good stuff from China but this wasn't one of them!

But a laser cutter is way too costly and way too complicated for me (and most people) to try to figure out what it really means....and to try to work out all the stuff that would be missing.

Actually back to the example of how good it would be for someone to write up a good manual, I have experienced that before with a very nice Futaba 8U Transmitter I got in 1998. The instruction manual was very readable, and understandable. But the issues were that it did not simply explain well enough about some things, and also only hinted at, or did not cover at all, how to do some of the more advanced features. So, a guy named Don Edberg had realized how many of the then new computer transmitters did not have very good documentation, so he wrote his own books on how to use and program those transmitters, including the Futaba 8U. He even personally told me how to do a trick that his book had the key info on but I did not realize how to make it happen, to use two negative mixes on a switch to make my shuttle orbiter rudder move the opposite way on boost than for glide (left rudder on boost acts like an aileron to make it roll right). I bought the book, and it was quite useful for many other things.

Sadly I have run into the SAME sort of problem with a popular transmitter of today, the manual for it is very readable, but the transmitter is so complicated that the manual does not cover even half of what it needs to. Someone claimed the Tx is so smart it does not need much of a manual, it leads you where you need to go as you run thru the menu options. But that's totally wrong, it often leads to blind alleys when you want to do something complex that it is certainly capable of doing.... but it is not capable of telling you how to find out how. I wish Edberg would write a book for the DX-18, or someone else to write a book. The usual solution for that is to go onto a R/C plane forum and hope the experts can help you figure it out.

Anyway, if someone would write a good solid $20-30 manual, or even a $50 book on how to make these cheap chinese laser cutters work right, how to tweak, and how to maintain them, they would probably sell pretty well.

- George Gassaway

georgegassaway said:

Someone offered to give me a 20 year old laser cutter that they used to use at their old job. An "engraver" type laser that he used for various rocket parts, on the side as he used it at work. The laser died. The quandary is a "free" laser cutter, but that the replacement laser for it costs about $1000, if the maker still sells old lasers to support the old machine.

So, I've been daydreaming about a "new" laser like the ones form China. The replacement laser itself is about $100. If I was really good at tinkering with machinery, in theory it might be possible to even mount the $100 laser onto the old "free" machine. But I'm not a good machine tinkerer.

One of he drawbacks ot me of any of the cheap ones, and evn a bit of an issue with others, is the software. The cheap chinese lasers use some sort of drawing software that seems like a real PITA to use, many users complain about it. I have seen a few that use CorelDraw. Although I do not use CorelDraw either, but it would be better to use something more common.

The best situation would be laser cutters that can be used like a "printer". So that one could use any kind of graphics or drawing software, and the laser could be adjusted to "print" at whatever laser intensity to do the desired effect, whether etching into wood to produce plaques, or to cut actual parts. Actually the old laser cutter my friend used has a manual capability to set the laser for an exact intensity for the job. He could adjust the laser power so fine as to be able to take a sheet of black decal paper (water transfer type), and the laser would burn thru the black decal but leave the paper uncut. So, the laser cut out perfect lettering for scale models. The cheapest chinese lasers seem to to have a crude means for setting the laser intensity ( a knob turning a potentiometer, the worst being that the laser intensity setting was displayed using a crude analog ammeter (rotating needle against a printed numbered background), instead of a precise digital readout). Ironically in some ways, the hardware cost for a digital display and simple up-down buttons to vary the intensity might not cost more than an ammeter and potentiometer (but it would require some software code changes in the controller board). Now actually I think that one of the cheap but not cheapest cutter DOES have a digital display and adjustment, but the apparent knockoff clones of that one use the ammeter/potentiometer method.

Anyway…. it is looking like the cost of the hardware is getting closer to being more practical. And inevitably someone is going to marry the cheap hardware with better software to make them far more practical to use.

And I sure hope that inevitably someone writes up good useful manual, not something in sketchy "Chinglish" or Google translated.

Actually when I was web-surfing a few months ago, I ran across someone who was making up a $100 driver board to replace the one in the Chinese laser cutters. IIRC the goal was to make it work like a "printer", so it could indeed use a wide variety of common graphics software, in place of being forced to use specific software. I might not be enough of a tinkerer to be able to work out how to bolt a new $100 laser into a 20-year old laser cutter not designed for it, but I think I could handle swapping out the control board (since the project is aimed at being reasonable to swap the original board with the new board).

I have a lot of other stuff to do for the next few months. Even if a laser cutter showed up tomorrow, I would not have time to learn to use it, it'd have to sit till September. But after things slow down, I'm going to take another look at what's available, at what price, and most important, how practical it would be to use it.

Now, I cannot personally afford it anyway. But, a friend is interested in having the capability, if I could draw up and cut the parts that he needed, and I'd get to be able to cut stuff for my own uses too. Maybe even offer some specialty items for sale.

I also daydream of some sort of 3D printer. But I have no experience with 3D software. I'm going to take a look at 3D software too next fall, see if there's something I can learn reasonably.

- George Gassaway

Click to expand...

Yeah, it's the "Moshidraw" software that must be used with the stock Moshi driver boards used in these that is the weak point. However, there are composition workarounds like this:

https://www.krekr.nl/content/142/

georgegassaway said:

I have run into the SAME sort of problem with a popular transmitter of today, the manual for it is very readable, but the transmitter is so complicated that the manual does not cover even half of what it needs to.

Click to expand...

Many times, as long as the item with no good manual has been around for a while, the web can be your friend with wiki pages and forum groups about it telling you what you need to know and, sometimes, even user written PDF manuals.

georgegassaway said:

Someone offered to give me a 20 year old laser cutter that they used to use at their old job. An "engraver" type laser that he used for various rocket parts, on the side as he used it at work. The laser died. The quandary is a "free" laser cutter, but that the replacement laser for it costs about $1000, if the maker still sells old lasers to support the old machine.

So, I've been daydreaming about a "new" laser like the ones form China. The replacement laser itself is about $100. If I was really good at tinkering with machinery, in theory it might be possible to even mount the $100 laser onto the old "free" machine. But I'm not a good machine tinkerer.

One of he drawbacks ot me of any of the cheap ones, and evn a bit of an issue with others, is the software. The cheap chinese lasers use some sort of drawing software that seems like a real PITA to use, many users complain about it. I have seen a few that use CorelDraw. Although I do not use CorelDraw either, but it would be better to use something more common.

The best situation would be laser cutters that can be used like a "printer". So that one could use any kind of graphics or drawing software, and the laser could be adjusted to "print" at whatever laser intensity to do the desired effect, whether etching into wood to produce plaques, or to cut actual parts. Actually the old laser cutter my friend used has a manual capability to set the laser for an exact intensity for the job. He could adjust the laser power so fine as to be able to take a sheet of black decal paper (water transfer type), and the laser would burn thru the black decal but leave the paper uncut. So, the laser cut out perfect lettering for scale models. The cheapest chinese lasers seem to to have a crude means for setting the laser intensity ( a knob turning a potentiometer, the worst being that the laser intensity setting was displayed using a crude analog ammeter (rotating needle against a printed numbered background), instead of a precise digital readout). Ironically in some ways, the hardware cost for a digital display and simple up-down buttons to vary the intensity might not cost more than an ammeter and potentiometer (but it would require some software code changes in the controller board). Now actually I think that one of the cheap but not cheapest cutter DOES have a digital display and adjustment, but the apparent knockoff clones of that one use the ammeter/potentiometer method.

Anyway…. it is looking like the cost of the hardware is getting closer to being more practical. And inevitably someone is going to marry the cheap hardware with better software to make them far more practical to use.

And I sure hope that inevitably someone writes up good useful manual, not something in sketchy "Chinglish" or Google translated.

Actually when I was web-surfing a few months ago, I ran across someone who was making up a $100 driver board to replace the one in the Chinese laser cutters. IIRC the goal was to make it work like a "printer", so it could indeed use a wide variety of common graphics software, in place of being forced to use specific software. I might not be enough of a tinkerer to be able to work out how to bolt a new $100 laser into a 20-year old laser cutter not designed for it, but I think I could handle swapping out the control board (since the project is aimed at being reasonable to swap the original board with the new board).

I have a lot of other stuff to do for the next few months. Even if a laser cutter showed up tomorrow, I would not have time to learn to use it, it'd have to sit till September. But after things slow down, I'm going to take another look at what's available, at what price, and most important, how practical it would be to use it.

Now, I cannot personally afford it anyway. But, a friend is interested in having the capability, if I could draw up and cut the parts that he needed, and I'd get to be able to cut stuff for my own uses too. Maybe even offer some specialty items for sale.

I also daydream of some sort of 3D printer. But I have no experience with 3D software. I'm going to take a look at 3D software too next fall, see if there's something I can learn reasonably.

- George Gassaway

Click to expand...

George.

I run Several Laser cutters at my Day job.. anywhere from 40 w to 180 watt co2

Yes lasers have a limited lifespan (co2 type) according to Epilog its about 4 to 5 years. at that point you cna replace the laser tube OR you can RECHARGE the tube.. (about 1/3 the cost)

So for the first one that was offered to you you might want to check in with the Manufacturer and see if they offer recharging services..

as a Co2 laser looses its charge the laser light does not react as quick as it used to..

so what you will see Mostly in RASTOR type usage is blurred images. tracking not straight etc but only at higher print speeds.

For Vector cutting you will see a need for increased cut POWER or a decrease in cutting speed to get the same job done. AND you will see again an inconsistancey in cut strightness. the top line will seem correct but as you cut deeper it will tend to no be straight. as if your laser is not centered or focused correctly.

We have one laser at the shop that has not been charged in almost 12 years. I should be able to do a rastor type print at 100% speed and lower power settings. but It just wont do it and look good. I run it for rastor prints (only in an emergence) at about 20% speed and lower power setting and still get a decent PRINT out of it. Vector cutting is fine as long as I am not cutting anything more than 1/2" thick. but I still run it at half speed..

Why dont we recharge it?? we have SEVERAL other machines that work perfect. this machine is very outdated, but in a pinch or if you need soemthing and the other machines are taken... I can make it work..


So to the original poster. YES a 40watt laser is nice you might be able to cut as thick as 1/4" plywood in a single pass with it..if it is all at 100% if not you can run it twice and still cut 1/4" ply and maybe more.

They are a great tool to have in your shop!

Winston said:

Many times, as long as the item with no good manual has been around for a while, the web can be your friend with wiki pages and forum groups about it telling you what you need to know and, sometimes, even user written PDF manuals.

Click to expand...

Very true. And in the case of the DX-18, it is so popular that there are good forum groups to go to, and a few PDF manuals for how to do some specific things, like setting up 6-channel electric sailplane that has flaps and ailerons (4- servos in a wing). IIRC, the pdf file to only do THAT is about 12 pages long.

That is the very sort of thing that I'd like to see happen with the cheap Chinese lasers. One can sometimes find a random thread here or there but nothing close to a "manual". And too often a case of the blind leading the blind..... new people relating some things they found out but nobody is an expert.

Well, there is one option for expert help. Buy the very same $600 "cheap" chinese laser cutter for about $1200 from a US company who will provide support. Which might be a viable option for a small business that needs to have a laser cutter. But too much for a hobbyist to justify, it's no longer a "Cheap" laser, it's a costs twice as much for the same thing laser.

As I say, I'll look at the issues again in the fall. At one point my friend was considering buying a $1000 replacement laser for the 20 year old engraver-cutter. A cheap Chinese laser cutter is a much more attractive option than that...... but for newbies things need to improve in the areas of documentation and practical usability (software).

- George Gassaway

stickershock23 said:

George.

I run Several Laser cutters at my Day job.. anywhere from 40 w to 180 watt co2

Yes lasers have a limited lifespan (co2 type) according to Epilog its about 4 to 5 years. at that point you cna replace the laser tube OR you can RECHARGE the tube.. (about 1/3 the cost)

So for the first one that was offered to you you might want to check in with the Manufacturer and see if they offer recharging services..

as a Co2 laser looses its charge the laser light does not react as quick as it used to..

so what you will see Mostly in RASTOR type usage is blurred images. tracking not straight etc but only at higher print speeds.

For Vector cutting you will see a need for increased cut POWER or a decrease in cutting speed to get the same job done. AND you will see again an inconsistancey in cut strightness. the top line will seem correct but as you cut deeper it will tend to no be straight. as if your laser is not centered or focused correctly.

We have one laser at the shop that has not been charged in almost 12 years. I should be able to do a rastor type print at 100% speed and lower power settings. but It just wont do it and look good. I run it for rastor prints (only in an emergence) at about 20% speed and lower power setting and still get a decent PRINT out of it. Vector cutting is fine as long as I am not cutting anything more than 1/2" thick. but I still run it at half speed..

Why dont we recharge it?? we have SEVERAL other machines that work perfect. this machine is very outdated, but in a pinch or if you need soemthing and the other machines are taken... I can make it work..


So to the original poster. YES a 40watt laser is nice you might be able to cut as thick as 1/4" plywood in a single pass with it..if it is all at 100% if not you can run it twice and still cut 1/4" ply and maybe more.

They are a great tool to have in your shop!

Click to expand...

An efficient CO2 laser tube contains either a 3 or 4 gas mixture. At a minimum it contains CO2 (carbon dioxide) which is the lasing media, N2, (nitrogen) which is an energy storage media, and He (helium) as a buffer gas which makes the electrical discharge efficient.

The pressure within the laser tube is sub atmospheric so the tube as to be as leak-free as possible, and the leaking of O2 (oxygen) into the laser head is a principal reason why the laser power decreases with age. The second is that the high electron current inside the tube will breakdown some of the CO2 into O (atomic oxygen) + CO (carbon monoxide) and O + O will recombine to form O2 which at the 0.5% level will quench the CO2 laser emission. Better lasers add CO as a 4th component in the gas mix to remove any oxygen and convert it to back to CO2 via the O + CO ==> CO2 reaction so that atmospheric leakage becomes the life limiting factor.

As O2 is generated, or leaked into the laser tube, the laser output power decreases and will eventually drop to a level where you can not burn through the material you are trying to cut. The cutting power requirement is non-linear so a small drop in power for a marginally sized laser can cause the device to fail abruptly.

A typical laser mix may be 8% CO2, 8% N2, 2% CO with the balance being He, but it is possible to go as high as 15% CO2, 15% N2, 5% CO with the balance being helium. Most folks do not have the capability to refill the laser tube at home so the only option is to purchase a new laser tube or purchase a factory reconditioned unit.

Having worked with CO2 lasers since 1976, I'm not sure how easy it would be for the average person to retube the inexpensive laser cutters. The alignment of the laser cavity and the laser beam through the laser optics is difficult for a non-professional as the laser beam is invisible and not eye-safe. If the replacement laser is a plug and play unit similar to the light source in as projection TV then it's not hard, but I can't believe that it could be done for $100.

On the other hand if a $500 home laser cutter lasts for 1000 hours, it's pretty much like a laser printer, by that time, a new better cheaper one has hit the market, and the easiest thing to do is to purchase a new one.

The current commercial units retail for 10X - 20X that price and are reparable, but the repair price will likely be more than the cost of the cheap $500 home unit.

As with any computer powered widget, good software makes or breaks the product because if you can't figure out how to use the software, the widget is useless and a waste of money. If the home unit is easy to use and lasts for 1000 hours, however, you should easily be able to make 10,000 parts (or more) before it give up the ghost. That's 5 cents or less per part......

Bob

bobkrech said:

Having worked with CO2 lasers since 1976, I'm not sure how easy it would be for the average person to retube the inexpensive laser cutters. The alignment of the laser cavity and the laser beam through the laser optics is difficult for a non-professional as the laser beam is invisible and not eye-safe. If the replacement laser is a plug and play unit similar to the light source in as projection TV then it's not hard, but I can't believe that it could be done for $100.

Click to expand...

Thanks for the info Bob , and everyone else.

In this case, at least one of the cheap Chinese lasercutters on Ebay lists spare parts available which include a replacement laser tube for $100. They include that offer so if the buyer wants to have a spare laser, they can buy it for no extra shipping when they get the laser cutter. Implied is that it is not hard to replace.

Of course it might not be likely that anyone can RTFM on how to do it when there probably is not a FM to R, or it's an F'ed up M.

Anyway, that's where I briefly toyed with the idea of using a $100 laser mounted into the 20 year old lasercutter, but soon realized that even if it might indeed work, it would take an expert to know how to install it (cutting metal, drilling holes, perhaps some wiring mods, and then the calibration issues).

When it comes to this stuff: I know enough..... to realize I don't know enough (tm).

Notably, the cheap lasers all seem to use a similar tube, with a small water pump to keep it cooled down.

A funny part of one Youtube video showing someone who had just set up their cheap laser, was how they were adding a LOT of ice into their water bucket pump reservoir to try to get the water to be at or under the 35 degrees that the info said it should not exceed (might have been 30). I find it incredibly unlikely that the water needs to be 35 degrees F or less, either the "FM" did not say Centigrade, or the user did not pay attention and assumed it meant 35 F and not 35 C.

- George Gassaway

georgegassaway said:

Very true. And in the case of the DX-18, it is so popular that there are good forum groups to go to, and a few PDF manuals for how to do some specific things, like setting up 6-channel electric sailplane that has flaps and ailerons (4- servos in a wing). IIRC, the pdf file to only do THAT is about 12 pages long.

That is the very sort of thing that I'd like to see happen with the cheap Chinese lasers. One can sometimes find a random thread here or there but nothing close to a "manual". And too often a case of the blind leading the blind..... new people relating some things they found out but nobody is an expert.

Click to expand...

I Googled "chinese laser cutter filetype[colon]pdf" and found this fairly good manual (better than the Chinese junk anyway) from a US company that appears to sell something very similar to the $530 laser this thread is about:

https://wiki.milwaukeemakerspace.org/_media/equipment/fslaser-40watt.pdf

Even though it's not identical, the principles would be the same when it comes to things like laser focusing and alignment. One big improvement of their laser over the typical, cheap Chinese one is the use of Mach3/EMC2 control card/motor drivers allowing excellent Mach 3 software to be used instead of the, supposedly, crappy Moshidraw software that requires workarounds to be really useful.

Moshidraw 2014

https://www.moshidraw.com/EnProductShow.asp?ID=96

Buy the very same $600 "cheap" chinese laser cutter for about $1200 from a US company who will provide support. Which might be a viable option for a small business that needs to have a laser cutter. But too much for a hobbyist to justify, it's no longer a "Cheap" laser, it's a costs twice as much for the same thing laser.

Click to expand...

What caught my attention is how much the cheap Chinese 40W lasers have dropped in price in just two years. Two years ago they were $830 shipped from China (no way!) and are now $530 shipped from the US.

As I say, I'll look at the issues again in the fall. At one point my friend was considering buying a $1000 replacement laser for the 20 year old engraver-cutter. A cheap Chinese laser cutter is a much more attractive option than that...... but for newbies things need to improve in the areas of documentation and practical usability (software). - George Gassaway

Click to expand...

For anything other than hobbyist use, the more expensive lasers would probably be worth it if they had good US-based support behind them. For me as a hobbyist, $530 is getting down into the very tempting range and I'd get "support" for any issues via Google searches and user forums.

georgegassaway said:

A funny part of one Youtube video showing someone who had just set up their cheap laser, was how they were adding a LOT of ice into their water bucket pump reservoir to try to get the water to be at or under the 35 degrees that the info said it should not exceed (might have been 30). I find it incredibly unlikely that the water needs to be 35 degrees F or less, either the "FM" did not say Centigrade, or the user did not pay attention and assumed it meant 35 F and not 35 C.

Click to expand...

I'll bet it is a misinterpretation of 35C as 35F and it's amazing to me that anyone would make that mistake.

Found this useful info while browsing about cheap Chinese laser cutters:

NEVER LASER CUT THESE MATERIALS

PVC (Poly Vinyl Chloride) : Also known as "vinyl" "pleather" "artificial leather." Emits pure chlorine gas when cut! Don't ever cut this material as it will ruin the optics, cause the metal of the machine to corrode, and ruin the motion control system.

LDPE : "Milk bottle" plastic. It tends to melt and catch on fire in low power (ex. 40W) lasers.

PolyStyrene Foam : It catches fire, it melts, and only thin pieces cut properly. This is the #1 material that causes laser fires!!!

Fiberglass : It's a mix of two materials that cant' be cut. Glass (etch, no cut) and epoxy resin (fumes)

Coated Carbon Fiber: Again, it's a mix of two materials. Thin carbon fiber mat can be cut, with some fraying. However, once coated with epoxy it will emit noxious fumes.

Winston said:

I'll bet it is a misinterpretation of 35C as 35F and it's amazing to me that anyone would make that mistake.

Click to expand...

On second thought, that guy may not have been making that mistake, instead trying to increase the laser output. Just found this:

"the cooling water was at around 14°C, which tends to result in reduced power (colder water is better)"

from

Thermal measurement of laser power (23/04/13)

https://www.imajeenyus.com/optical/20130423_measuring_laser_power_thermally/index.shtml

If there is a TechShop near you, give their machines a try before you buy. Laser cutters works really well for Acrylic, OK for thin plywood (some burning), but won't cut anything else we use in HPR. (I don't know about balsa.) More useful is a CNC router, which will cut all the same materials, plus more, and with higher speed and quality (right-angle edges instead of burned-out Vs), not to mention the ability to cut 3D shapes. (See my Aerobee fins for example.)

Laser cutters will cut balsa.

JohnCoker said:

If there is a TechShop near you, give their machines a try before you buy. Laser cutters works really well for Acrylic, OK for thin plywood (some burning), but won't cut anything else we use in HPR.

Click to expand...

Forum posts document clean cuts of 6mm (~1/4") wood, even thicker plastics, and what looks like 3/16" hardwood plywood in a video using one of the cheap 40W Chinese lasers. Agree that CNC routers would be better and I've had all of the wood and MDF parts that I've already cut for a "cheap" DIY one sitting in my work area for about a year now, but I'm always working on something else instead. I have the powerful but inexpensive router (bought a year ago when its list price was lower - stuff at Harbor Freight has been rapidly going up in price over the past few years):

https://www.harborfreight.com/1-4-quarter-inch-trim-router-44914.html

and router speed controller:

https://www.harborfreight.com/router-speed-control-43060.html

but still need the stepper motors and controller/driver boards.

However, the 40W laser cutting rate seen in videos is quicker and certainly much, much quieter and cleaner (no dust, just smoke that's easier to capture and route out a window) compared to CNC routers. Quiet and clean is important for my work area.

You should read this documented laser cutting/marking guide for plastics from Synrad, a major player in the industrial CO2 laser cutting/marking business as it also has good photos to back up the recommendations.

Industrial laser cutters usually have higher power lasers so they will cut thicker materials and cut faster than a 40 watt hobby unit but the comments are still very relevant. Plexiglas(R) (acrylic) and Delrin(R) (polyacetal) cut very well because they vaporize at very low temperatures.

Please note there are 2 glaring errors in the guide: On page 17 the heading Polycarbonate is correct, but below that, the name should be polycarbonate, and the AKA should be Lexan(R); and on page 18 the heading Polyester is correct, but below that the name should be polyester, and the AKA should be Mylar(R), PET, PETE, PETG.

FG and CF composite are cut industrially by water jet cutters, but fiberglass composites are frequently marked by lasers.

Bob

bobkrech said:

An efficient CO2 laser tube contains either a 3 or 4 gas mixture. At a minimum it contains CO2 (carbon dioxide) which is the lasing media, N2, (nitrogen) which is an energy storage media, and He (helium) as a buffer gas which makes the electrical discharge efficient.

The pressure within the laser tube is sub atmospheric so the tube as to be as leak-free as possible, and the leaking of O2 (oxygen) into the laser head is a principal reason why the laser power decreases with age. The second is that the high electron current inside the tube will breakdown some of the CO2 into O (atomic oxygen) + CO (carbon monoxide) and O + O will recombine to form O2 which at the 0.5% level will quench the CO2 laser emission. Better lasers add CO as a 4th component in the gas mix to remove any oxygen and convert it to back to CO2 via the O + CO ==> CO2 reaction so that atmospheric leakage becomes the life limiting factor.

As O2 is generated, or leaked into the laser tube, the laser output power decreases and will eventually drop to a level where you can not burn through the material you are trying to cut. The cutting power requirement is non-linear so a small drop in power for a marginally sized laser can cause the device to fail abruptly.

A typical laser mix may be 8% CO2, 8% N2, 2% CO with the balance being He, but it is possible to go as high as 15% CO2, 15% N2, 5% CO with the balance being helium. Most folks do not have the capability to refill the laser tube at home so the only option is to purchase a new laser tube or purchase a factory reconditioned unit.

Having worked with CO2 lasers since 1976, I'm not sure how easy it would be for the average person to retube the inexpensive laser cutters. The alignment of the laser cavity and the laser beam through the laser optics is difficult for a non-professional as the laser beam is invisible and not eye-safe. If the replacement laser is a plug and play unit similar to the light source in as projection TV then it's not hard, but I can't believe that it could be done for $100.

On the other hand if a $500 home laser cutter lasts for 1000 hours, it's pretty much like a laser printer, by that time, a new better cheaper one has hit the market, and the easiest thing to do is to purchase a new one.

The current commercial units retail for 10X - 20X that price and are reparable, but the repair price will likely be more than the cost of the cheap $500 home unit.

As with any computer powered widget, good software makes or breaks the product because if you can't figure out how to use the software, the widget is useless and a waste of money. If the home unit is easy to use and lasts for 1000 hours, however, you should easily be able to make 10,000 parts (or more) before it give up the ghost. That's 5 cents or less per part......

Bob

Click to expand...

SO true Bob.

I maintain the lasers I work with I have changed the tube after having them recharged... it it FOR sure a job to set up the tube to make it correct. but its well worth the effort!

again we have a couple of Epliog lasers and their customer support is second to none.. they will talk you through step by step if you need it!

I once wrote a manual in English that was later translated into Korean. I bet that worked out great!

What file format does a laser cutter accept? Is there CAM software for importing different design files and outputting manufacturing files for specific lasers?

ThirstyBarbarian said:

What file format does a laser cutter accept? Is there CAM software for importing different design files and outputting manufacturing files for specific lasers?

Click to expand...

The least expensive Chinese 40W laser cutters come with user unfriendly Moshidraw software and a controller board that uses it:

https://www.moshidraw.com/EnProductShow.asp?ID=96

About Moshidraw:

https://www.cnczone.com/forums/gene...77-making-moshidraw-2012-guide-formation.html

Working around it, using Moshidraw only as the required interface with the driver board:

1. Compose in anything that can output DXF R14 files (or DXG files that can be converted by a conversion app to DXF R14). Looks like the freeware Draftsight is popular for cutting:

https://www.3ds.com/products-services/draftsight/resource-center/?xtmc=draftsight&xtcr=2

and freeware Inkscape for picture engraving:

https://inkscape.org/en/

2. Import the DXF R14 file into a new Moshidraw document.

Another piece of free composition software:

Tutorial: Laser Cutting Techniques and Projects

https://makezine.com/magazine/tutorial-laser-cutting-techniques-and-projects/

"To facilitate this iterative process, I’ve developed a system of 3D modeling and easy 2D exporting of the cut files. While there are many software programs out there to do this, I find SketchUp Pro to be quite adequate for most of my needs when working on primarily orthogonal projects. My system requires only a basic knowledge of SketchUp. The Pro version is useful because it allows you to export DWG, EPS and other vector formats, but there are free SVG exporter plugins that allow you to do the same without paying for the Pro version."

https://www.sketchup.com/

Useful 40W laser cutter info I've accumulated from various online sources:

Air Assist

Airflow across the material being cut is also very critical. Make sure your exhaust meets or exceeds the manufacturers' specifications for air volume. A strong exhaust will reduce flaming and keep the residual smoke from damaging the material. Many materials flame when cut with the laser. This could potentially damage expensive optic components. A good exhaust will also help extend the life of these parts.

Another method to increase airflow at the cutting point is to use an air assist system available on many laser engravers. The air assist systems provide positive airflow at the hottest area and should reduce or eliminate scorching or flaming while cutting. By blowing the hot smoke and debris down and away, the overall quality will be improved with increased safety.

There are a couple of different designs for air assist assy. The most efficient way to introduce air flow to a laser cut is to run the assist air down through a nozzle straight down to the cut. This nozzle will have the laser beam run down through it and the air blows down directly into the kerf of the cut. You will achieve your most consistent cut results where the assist gas runs down perpendicular to the cutting surface. The only drawback to this design is, you have to have your air assist blower on whenever you are running with a nozzle on the system. If you don't have your assist air on when laser processing, these nozzles tend to act like a vacuum cleaner for all of the hot effluents to go up and build up on the lens. A very quick way to fry a lens$$$$$$$$$$$.

Another way to introduce air assist to your system would be to blow air across the cut area of your material. You are really only blowing the "flame" out or the effluents away from the plume, but for most laser engraving application that is OK. You can achieve this kind of air assist by running a tube down along the lens assy. of the machine, and point it towards the laser processing spot. Or you can blow air across the material from an air source at the front of the machine, and point it along the material being processed towards the exhaust port of the machine. The drawback to either on of these air assist designs that blow across a material rather than straight down into the kerf is, you will get a little different cut quality with different directions of movement from your laser system. Some directions, the will actually go down into the kerf, and others it will only blow across the kerf.

Misc.

1. what is the optimal strategy for cutting wood of 1/8 inch (no air assist yet, is this affecting cut time/burn?) ??my machine has the capability for changing cut speed through moshidraw.

With no air assist you run the risk of damaging the lens on that type of machine, it should cut 1/8th plywood without any real problems though.

2. what type of cheap air assist can i use? a aquarium pump? any ideas?

Hilea ACO280 or larger air pump will do the job.

3. what is the highest i can safely turn the power up to. can i turn it all the way to 30ma on the gauge?

Anything much above 16mA will kill the tube very quickly, above 20mA will cause stability / saturation problems.

4. for cutting, should i use multiple passes of high speed/ low speed with low power to reduce char? or is there a better route?

It can work but tends to be inefficient, air assist will solve most charring problems.

5. any free graphic software out there that exports in correct formats to use with moshi? coreldraw is 130 bucks and i would rather try something free

Inkscape for pictures and Draftsite for DXF cad files. Both free for personal use.


Old column (talks about $1000 cheap generic Chinese 40W laser cutters), but still has helpful info:


On cut quality (Note: he doesn't even use air assist)

This machine comes with a 25mm focal point lens, so the maximum thickness you can cut well is 1/4in (6mm) materials. If you switched your lens for a 50mm focal length lens you could have some more penetrating power. (The beam's effective focus range would be longer)

The cut quality is good in general, though there is a slight slant to edges that is 0.25mm to 0,5mm (approx.). This again comes from the beam focal angle, and easily fixed with another lens.

I almost exclusively cut 1/8in (3mm) materials for my projects so it works fine.

On the Laser Tube and Power

I’ve put hundreds of hours on the original tube that came with my machine and it has not failed me yet. I do use a water chiller to keep very cool water running though the tube at all times, usually around 40F.

I’ve also found that the temperature that the tube is at does greatly affect the power it puts out, in one accidental misuse of my chiller (it was turned off), the water circulating was pretty warm (60-70F) the power output dropped quite a lot, 30-40% in my estimation. (Note: he's lucky he didn't literally blow up his tube from what I've read elsewhere).

As for power, I’ve never had too many issues with my cutting 1/8th to 1/4th inch (3-6mm) woods and plastics. For thicker materials, I do find it desirable (less burny) to make more fast cutting passes a medium power, then one slow pass at high power.