Fun with a laser engraver

Jumper asked about cheap laser engravers in this thread, and I had already been thinking along those lines, and I have a friend with a Glowforge, and, well, things got out of hand. I have access to a pretty sporty 3D printer, but for some reason I could find more things I wanted to do with a laser. 

The engraver in question is an Ortur Laser Master 15W, which has a 4500 mW laser and is perpetually on sale from Gearbest. It took forever to ship out, possibly due to the Chinese new year. When it did ship, you could almost hear the sonic boom as it went from Hong Kong to a little Colorado town in about 72 hours.

I don't have a Windows laptop at home, so first step was to make it work with a Mac. Had to fiddle around a little bit to do a firmware upgrade to the engraver, but after a bit of time I got it fired up and recognized by Lightburn, the software I was planning to use. A little more fiddling to learn the software and it was burnin' time.

I had designed a little sugar skull cat for my wife's embroidery machine, so I used that for testing. Here it is at just under 2.5" high. I'm still playing with the speed and laser power - you can scale it from 0-100% and the speed can go as high as 9000 mm/minute. 

Janel also likes doing applique work but hates cutting things out, so here's what it can do with fabric. Okay, I'm seriously impressed there. This opens up some real possibilities, especially if you bring the embroidery machine into play.

Just for fun, I dropped an actual picture into Lightburn, converted to greyscale and hit "go". I could make it more legible with some tweaking but you can make it out and it shows how the laser can vary its power. It's only about 2.25" across - I didn't want to wait for anything bigger to "print". It's tactile, too. The darker areas are engraved deeper.

Here's the original picture.

I have some more material to play with, I'm going to explore this further. I think it'll be very useful to do custom labels, and with the ability to cut 1/8" wood I'll probably use it for some custom enclosures and little wooden models. I can also do circuit boards.

Jumper's original question was about making masks for etching plaques and labels, so I'm going to try burning paint off metal shortly and see how that works. It would be useful for my electro-etching experiments as well.

Who's got cool ideas?

Big question, how many times do you have to print the same thing in the same place to completely burn through your plywood and have a plywood cutout?

Overall, build quality seems quite solid. It even came with zipties and brackets for wire management. There's no wobble or slop in the mechanism, and running a second pass shows that it's very consistent.

A set of laser goggles came with it, but I also purchased a good set before the engraver got here just in case. 

I'm thinking of making a base for it so I can bolt it down. When it's running in full boogie mode, I can see how it might jump a bit and screw up the alignment. I'd also mark the origin on the base. You can tell the laser to go to a particular place on the layout and then turn it on a low intensity so you can confirm alignment, which is useful. I'm using 1%.

Mr_Asa said:

Big question, how many times do you have to print the same thing in the same place to completely burn through your plywood and have a plywood cutout?

I'm going to pick up the wood tonight to try this :) The engraver came with a sheet of recommended settings (power level, speed, number of passes) for various materials and I seem to recall that cutting through was 2 or 3 passes at 100mm/min. Not fast. I shall confirm tonight.

My friend with the Glowforge says that the trick is to prototype with cardboard.

In reply to Keith Tanner :

I'll definitely be interested to see that.

Pay attention to any "blow out" of the edges when you do.  As you cut through the distance from the laser to the cutting surface gets farther from the optimum focal length of the laser, so you start to get a kind of wider cut that doesn't look as pretty.  Bigger setups have a Z height adjustment that keeps the laser at the correct focal length to prevent the edges from getting funky.

This is a $175 laser, so it doesn't have the power or the adjustment of some of the others. I do have some fine-tuning ability for the laser height so I suppose it would be possible to drop the laser by 1mm after each pass if that was a problem. I was just going through the manual and realized I had the laser a little high when I was doing my testing.

Sounds like you have some experience with these, so maybe I should be asking questions of you :)

Keith Tanner said:

 

Jumper's original question was about making masks for etching plaques and labels, so I'm going to try burning paint off metal shortly and see how that works. It would be useful for my electro-etching experiments as well.

 

Keith you are my hero!

In reply to Keith Tanner :

I know just enough about these to be dangerous.  I've done some engraving and built one or two things by cutting them out and slotting them together using the tools available when I was in school.

Oh this should be fun!

I want to know what it does to polycarbonate. 

RossD said:

I want to know what it does to polycarbonate. 

Polycarbonate and not acrylic? I've seen what can be done with cast acrylic, it's nice and sharp. I have some polycarbonate chunks but my Glowforge friend says it doesn't cut anywhere near as well.

In reply to Keith Tanner :

Hmmm...yeah maybe acrylic too...

I bought a Death Star floating light thing that is just etched -- probably acrylic now that you mention it, that sits on end in a base with LEDs in it. I wanted to switch out the Death Star with a different design. Probably a Pikachu the size of a dinner plate on 1/4" thick sheet.

Good timing Keith. I was just looking at laser cutters/engravers the other day. That one is cheap enough to buy and play around with.

I have some ideas of things I want to make out of basswood.

I wonder if it will cut styrene cleanly or if the plastic melts and makes a mess.

Not a lot of time tonight, but I did shoot some metal. Laze? Irradiate? Burn? Zap? Pew pew?

Anyhow. 

I started with a sheet of aluminum that I used for test painting when I did the Targa Miata. It's actually two layers of car paint, orange over blue. I also sprayed a bit of high temp BBQ paint on the back, chosen because it dries almost instantly. 

I didn't realize how wobbly this was until I looked at this picture. The logo is about 2" across and I had the laser near the long end of the X axis arm. I'm thinking it must have been bouncing a bit on its feed with the rapid 90 corners and a pretty high speed with high power. I definitely need to make a base, and it might have worked better to slow down and drop the power level.

The paint didn't completely burn off - you can see where I tried to scrape it. Is it clean enough to etch? I don't know. The upper section (scratched) was actually done at half the speed of the lower, but it looks the same.

Then I flipped it over and tried the same settings. Interesting, I mostly took off the top layer. 
 

One last try. These squares are about 5mm across. The upper one was done as a cross hatch and a fairly slow speed. The lower was a single pass and about 5x as fast. Again, just the top layer and you can see some bouncing. But the slow version looks like it would etch well. Remember that I'm burning through two layers of very well cured automotive lacquer, so the faster version would be enough normally. 

This is what they give away at work for retirement; Keith you could start your own little cottage industry.

You're not wrong. It's basically an Etsy shop waiting to happen.

Just for interest's sake, I stuck a multi-layer guitar pickguard underneath. Then later I looked up the material - PVC, not the acrylic I'd hoped for. Still, here's what it did. The little quarter note is 17mm (11/16") tall. I do small stuff because it's faster :)

I played with power and the number of passes. On this one, the one on the left was filled and outlined. The middle one was just filled and slightly faster. The one on the right was the same as the middle and done through tape to see if that made a difference. It did, but not in a good way. The material is black in the center and white on the outside.

I didn't dig deep enough to get into the black, I think that's charring. So next I tried a white center. The lower note is two passes and higher power, the upper one is three passes at 80% power. According to my calipers, it's deep enough to be in the white but the charring keeps it from looking that way. I'm going to say that's due to the PVC. Very sharp edges, though.  The wobbles from the Martini logo are gone. I'll do some experimentation and see if I can replicate that.

So you could do crazy artisitic pickguards with this thing for your Etsy shop, but if you want that contrasting pop you'd probably be better off with a router. They're a little deep to be really useful so maybe just decorative squiggles on white would be more effective.

Spent the weekend skiing, but got a chance to do a little experimentation.

Got some cheap anodized "business cards" from Amazon. They engrave pretty easily.

Also got some anodized dog tag keychains. Let me tell you, not the same anodizing. The cards went through at 2000mm/min, the keychain took two passes at 250mm/min. It looks like a nice sharp engraving but I had trouble photographing it. The cat is the same scale as the last one.

One of the things I've been doing has been to build an outline of the thing I'm engraving, then burn it into the piece of wood I'm using as a base plate. It makes life a lot easier to align everything.

That's the pattern for this - a real carbon fibre "horn button" made by another GRMer years ago. You can see the base circle running through the center of the holes.

And I decided to customize the cover for my Kindle. Leather is...pungent. This is 45mm across.

I need to play with some masking for etching still. Have to find a good base paint for it, but I'm getting more comfortable with the tools. I can tell you that transparent acrylic doesn't work - I know it can be done, but maybe it's a wavelength thing - and it can scorch fiberglass but not much else.

I dont have pictures of it, but I etched the coating off some Kershaw pocket knives for my groomsmen.  When I did I used the laser cutter to cut a pocket out of 1/4" laminate for the knives to lay in.  Let me place it perfectly the first time.

If you haven't already, a base template that the thing can bolt to and that has the X and Y axis as hard edges would probably be useful.

I thought about a base, but one advantage of this fairly small unit is that I can actually put it on top of things without being limited by a base plate. I also wasn't sure what material I could use. With the piece of plywood, I can draw out my X/Y axes and just screw the laser on top. When the wood gets too scarred up, I replace. At least, that's my current thinking. I'm still experimenting to find out where I'm bumping into limitations.

The software lets me move the laser to a specific point and then turn it on at extremely low power, so I can use that for alignment if I want. I've done that to double-check exactly what the borders of something will be, and I can also do a low power/high speed runthrough.

Doing that sketch of the horn button meant I was able to easily center the Martini logo using the "align center" tools in the software.

Spent more time playing with different materials and setup.

Focus. Focus is important. And pretty difficult to get just right, honestly. There's a gross adjustment for thick material and then some fine adjustment for the lens. And as far as I've figured so far, you have to just eyeball it. Still, I'm seeing some improvements.

These little guys were the result of both power/speed and focus adjustments. The single lines are nice and sharp.

We use dog tags for keychains for our NDs at work, and I never did get around to ordering a set for our 2019. So I made some. Note how the Jones is silver on the lower one, that was two passes. The others were all one, and they've got a golden sheen to them. That's a trick of the black in particular.

I played around a bit with 1/8" plywood without much success. I think the problem was focus. I could get 95% of the way through consistently but the last 5% was difficult. The amount of burning is - I think - a result of poor focus.

One advantage to this little engraver is that it can burn just about anything. So I gave my workbench a tattoo.

That tattoo was super-clean, so I pulled out the sample plywood cards and played with them. They're sanded smoother than the big sheet of 4x8 stuff I bought from Home Depot.

Janel said "put a loop on those and they could be earrings!". So I did. She's wearing them now happily.

I decided to push even further. The website makeabox.io will create a PDF of a box pattern for you if you give three dimensions plus material thickness. I added some circles and made this little guy. Not perfect, but it was educational.

Also, Janel bought this music box online - it's pretty clear how it was made. I had to disassemble it to fix a loose part.

So that's the crafting report. What have I learned so far?

- this is not as powerful as a CO2 laser, not even close. If you want to cut through material, you need to have patience and do a fair bit of trial and error for every material.

- the manual focus is tricky.

- you can get a CNC milling machine that can carry a laser head for about $100-150 more than I paid for this thing. That would open up a lot of options for other materials and potentially adds focusing capability since it can set the Z axis. That's nearly double the cost but I think it would be a lot more flexible.

- as always, more power is better :) But I have found that some materials benefit from running slower with lower power, so it's not always the right choice.

- high speed y movements can cause a bit of a "bounce", which is where the wiggles in the Martini came from a while back. I work around that by running a bit slower when I'm working with something that might cause a problem.

- it's great at removing anodizing, burning patterns into wood and cutting fabric. All of those will be useful to me. It should work well at cutting masks for etching but I haven't done an end-to-end test yet.

- it's not good at engraving clear acrylic (making copies of amazingly expensive "rulers" for sewing), copper (PCBs) or fibreglass. I haven't tried ceramic yet.

I ordered mine over two weeks ago and it sat with the label "not shipped" all that time. Last night I decided that it was foolish of me to have checked the 7W option and I fired up their support live chat and had them change it to the "15 watt" version.  They sent me a Paypal invoice to cover the difference and pretty much as soon as I paid that I recieved an Item shipped email and the website lists it as shipped, but still as the 7W item.

I don't have much faith that I will get what I want in this transaction, but I have been surprised before.

I have already enlisted the help of a graphic designer to start designing the machine tags I want to make.

And as if on cue the latest "hand tool rescue" video shows him doing exactly what I have in mind at about 20 minutes in.

Keith Tanner said:

- you can get a CNC milling machine that can carry a laser head for about $100-150 more than I paid for this thing. That would open up a lot of options for other materials and potentially adds focusing capability since it can set the Z axis. That's nearly double the cost but I think it would be a lot more flexible.

Curious about that option:  Is there one in particular that you're thinking of?

I just did some searches on laser engravers. 

Turns out getting a tattoo on your skin from a laser engraver is a thing.  

wae said:

Keith Tanner said:

- you can get a CNC milling machine that can carry a laser head for about $100-150 more than I paid for this thing. That would open up a lot of options for other materials and potentially adds focusing capability since it can set the Z axis. That's nearly double the cost but I think it would be a lot more flexible.

Curious about that option:  Is there one in particular that you're thinking of?

If you look at Amazon, there are about 300 versions of the same "cnc milling machine" with the same basic model number 3018. I don't have any direct experience with them, but as long as you're willing to fiddle and were realistic about materials I think you'd be satisfied. Reviews seem promising.

Trent, my ordering experience wasn't much better. They sat on the order for something like three weeks before shipping, then it moved like a rocket.

My wife has a sewing machine with an embroidery attachment. Frustrated with the ridiculous prices for off-the-shelf embroidery patterns and the name brand software, I did some work with an open source software package and made some designs for her. Let me tell you, it became pretty obvious pretty quickly that controlling the machine is the easy part. Designing a mechanism to stitch consistently and then setting up all the tensions and thread types and etc is very different. No wonder you don't see the embroidery equivalent of these lasers and CNC mills.