OMTech K40 Laser
The Chinese laser often referred to as the K40 (40 watt) is an entry level CO2 laser at a magnificent price point. They can be had for around $350 to $450 dollars depending on where you get them and how you get them configured.
I got mine from a place called OMTech for about $420. It is also were well configured and has many upgrades already included.
Right out of the chute these things engrave and cut well although the 40 in K40 seems to be a bit of a gimmick. A lot of the included laser tubes are actually 30 to 35 watts. It’s really not enough to kick a fuss up over. It’s just the way it is. So that kicks off the upgrade discussion. You can buy larger and more powerful laser tubes.
Once you use one of these things a bit and learn your way around one you’re going to want to upgrade some things. While they do indeed come at a magnificent price point the old adage applies. You get what you pay for.
Let’s go over a quick list of things you are going to want to upgrade.
I have an Ortur Laser Master 2. Very, very nice low powered diode laser rig capable of making some great craft items. I also have a larger K40 Laser however sometimes it is like trying to use a sledgehammer to drive a nail. The Ortur has great flexibility because of how open it is and the fact it can be set on any surface or pass materials through it or raise it way up high.
Make no mistake though, the Ortur Laser Master 2 is NOT a production machine. It was not meant to be run full power, all day, every day. It is a hobby device for hobbyists. If you push it beyond that…….well…….good on ya.
There do seem to be some issues with the laser though. Some users report 100% laser power 100% of the time and frequent disconnects, not to mention the fact they can’t connect at all to the computer. So there are issues going in……………
It CAN be a production device though with some pre-planning and regular maintenance.
Let me tell a somewhat unrelated story. I like solar power and solar powered generators such as the company Jackery makes. Every time they release a new one about 50 clowns on the internet say “This is bullshit. This will only run a refrigerator for 14 hours and my heart transplant kit needs to run for 15 hours.”
My response to that is always this: “So buy two of them!”
Do you see where I am going with this?
A K40 with a digital control doesn’t actually indicate actual laser power. The only way to reliably measure the current from a laser tube is to add a milliamp (mA) meter to your K40. While there are a lot of differing opinions on max power draw most agree it is somewhere between 18 and 20 mA’s. Some people even pull short at 15mA to improve tube longevity.
Adding a meter is SIMPLE. Locate the Black wire on the EXIT end of the laser tube. That is the end closest to the mirror. That black wire will be spliced to another wire that runs all the way to the L connection on the Power Supply.
K 40 Laser Tube (L) wire
I recently bought a K40 Laser from OMTech. Most people use a free software mix for the K40 utilizing Inkscape and K40 Whisperer but there is a far better software solution (not free) called Lightburn.
I liked K40 Whisperer and was getting the hang of it. It’s actually pretty powerful and it really is a good hunk of software but it just isn’t Lightburn. No knock at all on K40 Whisperer intended.
Most K40 lasers come with a control card called an M2Nano which is not compatible with Lightburn. The only way to run Lightburn on a K40 is to purchase a new controller card. There are several options out there but I went with the Mini-Gerbil from AwesomeTech. I just got the card and installed it and as always took notes while doing the installation and ran into a couple of noteworthy things that I thought was worthy of a blog.
There are SO MANY K40 variants that it is hard to say that anything I took note of is a problem.
“Let me just throw this out there…….If you bought a K40 laser and realize you need a new control card and aren’t scared in the least to change it then nothing I note here is above your skill level. I don’t view anything as a mistake or documentation error. There are simply SO MANY K40 variants out there it is tough to cover them all.”
I recently bought an Ortur Laser Master 2 which is marketed as a 20 watt laser but it is truly about a 5 or 5.5 watt output power diode laser. It’s an amazing device for engraving wood and cutting thin materials. In other words it has some limitations. I’m having so much fun with it but the forums are full of stories of parts failures. If you have a hobby device and it fails it’s not the end of the world, however if you are making money with the device you probably should have a 2nd one at the ready, or at least buy spares, such as another controller board and laser module.
So that’s where I’m at. I made my first couple of sales and I realized that if I can make a buck or two I’ll lose credibility real fast if my machine goes down and I can’t deliver. So I decided to pick up another machine. After all they are cheap. Around $300 or so.
K40 Mini Laser
Then I (re)discovered the K40 Laser. K40 isn’t a name brand but rather a gigantic swoosh covering a range of inexpensive cloned Chinese 40 watt CO2 lasers. K40’s are made by several manufacturers and sold by untold number of secondary retailers especially on the Chinese electronics websites (Aliexpress, Banggood, etc.) and eBay. The quality range varies from great to absolutely horrific. You need to carefully source your supplier and do lots of research before buying one of these things.
That being said, these machines are a platform for upgrades and lots of the people who buy them don’t much care if they work or not. They will make them work and improve and upgrade them in the process. In fact I’d love to find one broken that someone was selling for a song. After 48 hours with this thing I’m pretty confident I could rebuild one and repair parts can be sourced cheaply.
Getting a great finished product isn’t always easy. I like to think of these processes the same way you might think of a meticulous old machinist or a pilot going through his checklist.
Working through these things slowly and methodically will help you achieve better results.
Let’s get started, shall we? My first piece of advise is to treat every job like it is the first job you are ever doing. Be slow and work purposely making sure not to forget ANYTHING. Let’s roll!
1. Inspect the piece you intend to etch on. Make sure it is smooth, flat, sanded, has an even coating of whatever you put on it and is prepped to your satisfaction. Poorly prepped parts will spoil your final product.
2. Second of all you need a GOOD, FLAT, SECURE surface. Etching a grid on it is really beneficial for keeping your work piece straight. Cut on a waste board and clamp that board down to your work surface if you can.
Use Your Grid Lines!
Ortur YRR Rotary Device
Picked up one of these Ortur YRR Rotary Rollers to supplement my Ortur Laser Master 2. There are a lot of videos online showing you how to assemble it as it comes in a kit form but not much information on how to make it work in software.
That’s why you have me.
I spent a couple days researching how to set it up and never really found an “AHA” video or webpage but after viewing a dozen or more items I had a good idea of what to do.
I’m going to set mine up in Lightburn which is a pay program ($40). If you have a GRBL laser cutter, Lightburn is worth every penny.
Connect your Ortur Rotary Roller to the Y axis with the supplied extension cable.
No shortage of reviews for the Ortur Laser Master 2 and as always I won’t bore you with the things you can read anywhere else, like what models are available and what the real laser power is, etc. You can get that info anywhere.
This is MY shakedown and I like to bring up the things the layman and weekend hobbyist might come up with.
First of all the cheapest place to buy one is Gearbest. You can get the top of the line (20 watt) for about $290. So I ordered one. And I waited and I waited and I waited and the status on Gearbest still showed it not being invoiced. A lot of people on a lot of forums were saying they waited for months.
You can however just order one on Amazon and have it in 2 days. This is what I eventually did. The downside is that it costs like $120 more. I can live with that.
I got the box which was well packaged and the kit was complete. Assembly takes 30 minutes or so, however if you were building your 2nd one it would take about 10 minutes. Translation: The instructions are small and hard to read. I ended up watching an assembly video on YouTube which made the process much, much easier.
Ortur Laser Master 2
I got one of those Ortur Laser Master 2, laser engraving machines. This is not really a review of the machine but suffice to say that I think it is awesome.
It is not the end all, be all machine for laser engraving for sure but it is WAY more than enough for most hobbyists. Also it will do things that technically it isn’t supposed to do thanks to the ingenuity of community of people behind it.
Rather this post is about adding Air Assist to the laser. In short if material is too thick to cut and takes many passes an air assist system will speed things up and produce much cleaner cuts free of smoke and burning. In the picture below you can see evidence of burns in the lines and especially where the lines are close like in the “E” and the top of the logo.
Slight burning marks on logo and prominent on “E”
Here is the exact same cut, using the exact same settings, with Air Assist in the pic below.
Same settings with Air Assist