Session 31 – Laser Cutting: Where Do We Start?

The Concise RDWorks Learning Lab Series

Welcome to Module 4 of the new Concise RDWorks Learning Lab Series with Russ Sadler. Module 4 will build on the information learned in the previous modules and will be targeted on the process of laser cutting. Russ will explain the science behind the laser cutting process and go on to demonstrate the techniques needed to consistently achieve great laser cutting results across a variety of materials. So, Laser Cutting? where do we start?

In this Session, Russ explains why the current optical lens theory does not apply to laser cutting and explains in detail how the laser actually interacts with materials. He then goes on to explain the importance of intensity within a laser beam and why it has such a huge impact on laser cutting performance. Find out if your laser beam is “BLUNT” or “SHARP”!

Release Date: 11th February 2022

Over the last 6 years, Russ has built up a formidable YouTube following for his RDWorks Learning Lab series which currently has over 200 videos.

The original RDWorks Learning Lab series on his “Sarbar Multimedia” YouTube Channel, follows Russ as he tries to make sense of his new Chinese laser machine and to sort out the truths, half truths and outright misleading information that is available on the web.

Six years later with over 3 million YouTube Views under his belt, Russ has become the go to resource for everything related to the Chinese CO2 laser machine user or wannabe user.

Laser Cutting Power Intensity Overview
Laser Cutting Power Intensity Overview

In this new series, Russ has condensed his knowledge and experience of the last 6 years to provide valuable information and insights into the purchasing, understanding, use, repair and maintenance of the Chinese CO2 laser machines and their key component parts.

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Session 31 – Cutting: Where Do We Start?

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Session 31 – Cutting: Where Do We Start?

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Transcript for Laser Cutting: Where Do We Start?

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The Concise RDWorks Learning Lab with Russ Sadler.

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Session 31 Cutting: where do we start?

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Well, you’ve seen this before. It’s a lens! You’re very familiar with lenses now because you’ve been using them for all your engraving.

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We’re going to change the subject now. Because we’re going to talk about cutting. Now if you

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remember, way back in session 18, when we opened up the discussion about engraving.

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I said there was no such thing as an engraving lens all lenses are basically cutting lenses.

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Well. That is essentially true. But before we get to the lens, we’ve got the laser beam.

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It’s a very common term in computer language. Rubbish in equals rubbish out.

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Well, it equally applies to this. This is only an amplifying device for intensity, light intensity.

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If you put rubbish light intensity in, you’ll get more of it out.

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It’ll intensify it, but it won’t intensify it very much.

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You get out an amplification of what you put in.

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Now everybody knows what lenses do. You’ve seen this picture before back in session eighteen When we introduced you to lenses for engraving.

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And you may remember at that point, I said this picture is total rubbish.

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This is what the lens manufacturers would have you believe happens.

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Well, you’ve already seen that. We don’t need the focal point.

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We don’t need the intensity that they talk about here to do engraving. With engraving,

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we just want to damage the surface of the material. Most of the time.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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And so consequently, we’re not interested in this very, very fine focal point here.

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And the very high intensity that they claim for that focal point. You’ll notice

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the cynicism in my voice, because I’ve spent a long time trying to understand how lenses cut.

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And lenses do not cut the way that you believe.

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Let’s take a look at this one as a classic example look, the rays come in, they hit the focal point,

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which happens to be the surface of your material and you get huge intensity of light at that point to do damage to your material.

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What then happens to that light? It dissipates. Now you remember when we were trying to find the way to get a soft beam,

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that only damaged the surface of the material and did not cut into the surface of the material. We had a lot of trouble.

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This was an inch and a half lens that we were using and we had the power turned right down.

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But we still were penetrating into the surface here with this very deep cut.

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I mean, this is somewhere in the region of about two millimeters thick.

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This top layer of material on this plywood. When we turned the power up to 100 percent.

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That same lens was able to do this amount of damage to the material, it’s gone right through.

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Is that the sort of cut that you’d expect after the focal point?

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Look what’s happening to the beam after it passes through the focal point. Look, here it is, you can clearly see it comes to zero and then it grows again.

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The lens that I used for this job was focused onto the top surface of the material.

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So two questions arise; Number one. Why have we got a cut?

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And Number two; look at this.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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It’s not just a cut that passes through the material because I’ve increased the power, that should not be possible according to that drawing,

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because the intensity is now doing this.

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It’s diverging at an alarming rate and there’s no intensity there to actually cut through that material.

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Now I’ve approached, learned professors of physics.

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I’ve approached senior people in the laser industry that design these machines,

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and I’ve approached the lens manufacturers to ask them, can they explain why and how their lenses do this?

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As you might expect, the people in the lens industry basically tell me to go away.

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What happens after the focal point and how you use and apply the lens is basically your problem.

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People in the laser industry and learned professors come up with all sorts of maybes, things like; Well, you know,

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once you start producing a gas in here, the laser beam finds its way in somehow and it vaporizes or ionizes

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the gas inside there and it gradually finds its way through?

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Did you believe that? It sounded like Bullshit to me, to be honest.

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So the first thing that we must say is, you must throw away all your conceptions

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of how lenses work because they do not work the way that you think they work.

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Crude lens theory was around in the time of the Greeks. The Egyptians used it.

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Then we get as far as the Middle Ages, where people like Galileo started inventing the telescope and Kepler and people like that.

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So this lens theory? Tracing of rays like this.

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Look, we’ve got rays, we’ve got rays. That’s the outline of where people think the beam is. Lasers themselves,

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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have only been around for about 60 years. Serious industrial application for cutting materials probably only about 30, maybe 35 years.

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So this is a very young technology. People that design these laser machines,

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they take their technology and put it through something that’s been existing for hundreds of years.

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It’s a proven technology. Why would you question it?

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Here’s how it works. Well, now I’m afraid it’s your misfortune that

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you’ve encountered somebody that does not believe any of this.

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Essentially, there’s nothing wrong with the lens theory.

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If you had a camera, a telescope, a microscope, a projector.

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This stuff works a 100%. It’s well proven, but when you throw a laser beam at a lens, that’s not the same as throwing an image,

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which has got fairly uniform light across the image.

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No, we’re interested in only one thing; light intensity. Light intensity is the thing that causes material damage.

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Remember how material damage happens, you’re busy shaking molecules and the more energy you can put to shake those molecules,

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the faster you will be able to create damage. We’ve created damage here, which tells us exactly what the profile of intensity is. Here,

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we’ve got a parallel beam which doesn’t really tell us what the profile of the intensity is, but it tells us where the intensity has passed through.

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And look, if we look just here, you will see down at the bottom here, we’ve got a hint of this taper.

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Yes, we’ve broken through the bottom, but we haven’t broken through with the beam fully.

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We’ve still got part of the tapered beam there.

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So in the instance of this cut, it’s very interesting to see that we’ve got two different types of material.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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We’ve got material which is this type.

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Then we’ve got a softer material, which, if you look, has got a little bit more damage taking place and then we’ve got this harder material again,

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and then we’ve got this softer material again, finishing up with the hard material.

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And you can see the slight difference in damage as the beam has passed through all of those different material structures.

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Now the other observation that I’d like you to make is the whole of this surface here has been cut with the laser beam.

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But you notice this is a different colour to this, but it’s all wood.

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This happens to be end grain. This happens to be long grain.

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So the grains are going in the opposite directions and you can see here, look,

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we have got a certain amount of dark brown in certain parts of this grain structure.

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But other parts are completely white, and uncharred. I said to you, that engraving was a complicated process.

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Cutting is actually simple. But just as complicated in different ways, because then you need to understand much more about the materials themselves,

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the damage that you caused to materials when you’re only trying to mark the surface.

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You’re not worried about penetration and rate of damage. In fact, if anything, we were trying to do exactly the opposite.

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We were trying to minimize the amount of damage that we put onto the surface and just produce this brown scorching.

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We found how difficult that was because look, this little cut here, even though it’s done with high intensity light, is not brown.

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Remember, we looked inside that and we saw that it was absolutely clean.

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What you saw from the top as a black line was, in fact, the occlusion of light, just the fact that it’s a deep groove.

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This has got some sort of charring, some sort of carbon surface that’s left behind.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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You can see from my little torch here that I’m shining on the surface.

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There is no real edge to that beam. It’s very, very bright in the centre and it sort of tapers away to almost nothing on the edge.

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Well, that’s the intensity of the light disappearing towards the edge.

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High intensity in the center. Low intensity at the edge.

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Well, that’s what that picture shows us.

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That’s exactly the situation happening within a laser beam.

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The perfect laser beam will have an intensity distribution. As per this curve.

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It’s a curve called a Gaussian distribution curve.

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Even though the proportions of it might change.

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The same mathematical formula is used to generate this curve, regardless of what the shape actually happens to be.

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Now what I’ll show you here is a beam that is seven millimeters diameter.

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I’ve just chosen some numbers here. They’re just numbers to show the relative differences and what happens within a laser beam.

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This curve represents two properties of the laser beam.

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On the one hand, the area underneath that curve is its power.

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Now, in this instance, we’ve made it 50 watts and the area is 1621 square millimetres under that curve.

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So 621 square millimetres represents 50 watts, and that happens to give us a curve, which is a height of 50mm.

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Now, if we keep the base dimension of this mathematical formula the same and we change to 100 watts.

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Well, if we go from 50 to 100 watch, we expect the area to go up by double.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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And sure enough, here is look 3242. But 3242 area with the same base has caused the curve to change to this shape.

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This is a sharper curve, then that one, let’s call that one blunt and this one sharp.

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If you buy a 100 watt tube. To replace the existing 50 watt that’s in your machine, you will get twice as much cutting power from it.

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Well, sorry, that isn’t the case.

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That isn’t the way it works because generally when you buy a more powerful tube, the diameter of the beam increases as well.

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And so now we’ve gone from 50 watts to 100 watts, so we’ve still got 3242 as our area.

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But because the diameter of the beam has increased. For the same amount of area under there, and you would expect the intensity to double.

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It’s only gone from 50 to 77, so it’s only a 50 percent increase in intensity for a doubling of the power.

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Now here you’ll see a block of, a little block of acrylic and I’m going to fire the laser beam at this block of acrylic.

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Now, just down at the bottom here, you’ll see that I’m blowing some air at where I’m going to fire it, because I don’t want it to catch fire.

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But this is about 70 watts of power on a

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probably what the manufacturer claims to be a five or six millimetre beam.

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Now, if you watch, you’ll see the centre of that beam growing at a much faster rate than the outside.

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The Outside is staying virtually the same diameter. And there we go.

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Let’s stop there. So that’s the outside diameter of the beam.

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And this is the centre of the beam, which has done a lot more damage to the material because of its higher intensity.

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This is not a focal point. There is no lens in this system.

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The sharp point on this burn is nothing to do with focus.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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It’s all to do with the intensity distribution within the beam itself.

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This part of the beam has got a much higher intensity, so it’s burning forward at a faster rate.

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This little demonstration is probably the most important demonstration that I can make to try and illustrate how cutting works.

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It took 10 seconds roughly for, say, a six millimeter beam to burn through 25 millimeters of acrylic.

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Now that’s just a gauge for you. But that is the shape that you’d expect from a cutting beam.

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Now I’ve turned the power right down to 15 percent. And here you’ll see what happens for the same 10 seconds of burn.

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So you will notice the bubbling that took place in there as the acrylic was boiling and then it vaporizes and turns to acrylic vapor at 200 degrees C.

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But look how relatively blunt the beam in.

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So there’s the sharp beam at the bottom with its 10 second burn.

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As I’ve illustrated here, 10 seconds of burn produces this sharp form.

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Here we’ve got a blunt beam because we’ve turned the power right the way down.

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OK, so it’s not doing the damage as quickly, so we can get both a sharp beam and a blunt beam out of my tube just by adjusting the power.

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We went all the way through a piece of 10 millimetre thick material with this shape of

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beam and this shape of beam was doing just the smallest amount of damage on the surface.

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The point I want to stress here is that the beam itself is very important to your ability to cut.

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Many of the tubes that you buy online are basically junk.

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They cannot perform this function here of a sharp beam.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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They will only be able to do something like this, fine for engraving.

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No good for cutting. Now this is a gaussian curve, which very conveniently,

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I’ve just made six millimetres diameter because look, we’ve got one millimetre, two millimetres, three millimetres either side of the centre line.

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The first central two millimeters of the beam contains about 70 percent of the power.

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The blue sections around the outside each contain about 10 percent and the remaining five percent each side

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here, is the remnant part of the power, right at the extreme edge of the beam.

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Power is not the same as intensity when we allow that beam to fire into a piece of

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material after one second, two, three, four, five, six, seven, eight, nine, 10 seconds.

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This is the shape that we will get, a nice sharp burn.

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Now it’s important to remember these three coloured zones. This red zone has got virtually no intensity in it.

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The blue zone? Well, it’s got some moderate intensity in it, but the real working zone of your tube is this high intensity part of the tube.

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So let’s move our attention away from the beam itself. Remember rubbish in, rubbish out.

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This is not rubbish. This is a good quality cutting beam, and we’re now going to talk about what happens when we pass it through this amplifier.

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This energy amplifier, which you call a lens.

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The most common lens that you’ll come across is something called a plano convex lens. Flat on one side, curved on the other.

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The way in which these lenses are designed, is for the light to come in, in a parallel manner.

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Parallel to the axis of the lens itself, and pass through the lens to something called the focal point.

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You can see that I’m pointing here at something which appears to be the focal point.

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But if we look at this a little bit more carefully, what you’ll see is that all the rays are not actually focusing at one single point.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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There is a range of focal points that’s happening here.

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It’s manufactured with a spherical surface, and that spherical surface has a property called spherical aberration.

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An aberration basically means that it doesn’t all finish up at one fixed focal point.

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If we look carefully, you’ll see that these rays from the outside are actually crossing over here.

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Whereas, the rays from the centre are crossing over here.

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So there’s a difference between the focal points across different diameters of the lens.

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So it is incredibly difficult to get a decent single focal point out of a plano

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convex lens. If we use the lens the wrong way round and we put our parallel rays of light onto the flat surface of the lens,

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aberration becomes absolutely ridiculous.

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This is an exaggerated picture. It demonstrates exactly what happens when you flip a lens over. These rays from the

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outside focus at an even earlier point than they did when it was used the right way round.

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And look at these. Look at the discrepancy between the focal points of all

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these various rays that are coming in from these disparate parts of the lens.

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And let’s have a look what happens to these red rays from this low intensity region of the beam?

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So here are these red rays. And we’ve got another one here.

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So there’s our red zone. Hitting the material, there’s not much intensity there.

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Let’s take a look at these rays that are coming in from the blue zone.

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So there we are. Look, we’ve got our blue zone coming in and it looks as though our blue zone is actually focusing onto the surface.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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It is very small, so we have still only got around about 10 or 15 per cent of the available intensity that we’re applying to that surface there.

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Now this yellow zone is not focusing until we get down to here,

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and it’s only at that point that we get a true central focus onto the surface in the material.

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Most of you guys will be using your lens this way round. You will get moderately good cutting if you use the lens this way round. Because

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there is sufficient aberration in here to still create this filtering effect.

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Now these learned professors and these lens people don’t happen to have one of these machines tucked away in their shed in their back garden.

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So they’ve got no idea of how their lens actually work,

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when we ask it to cut material. But my study of the way in which lenses and laser beams work together start to reveal

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this strange mechanism, the filtering mechanism that’s caused by lens aberration.

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Lens aberration? That’s the last thing that you must talk about when you speak to a lens manufacturer. Aberration is our friend, not our enemy.

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Now, as I’ve said, it’s taken me a long time to decode how cutting works.

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But one of the interesting stages in that progression was this experiment here that I carried out.

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You can see that we’ve got parallel rays of light coming from our laser beam, which has got variable intensity firing at a piece of material.

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Now you’ve seen this experiment, 10 seconds fired into that material produced a point at the end of the acrylic block.

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There is no lens in that system. That point was all to do with the intensity difference between the outside and the inside centre part of the beam.

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Here we’ve got a lens which I’ve put into this system. It was a very, very long, focused lens.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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It started off here at, say, six millimeters diameter,

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but at the time it got down to here it was maybe five millimeters diameter because the lens had already started to decrease the diameter of the beam.

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But look, I produced exactly the same sort of pointed burn,

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but this time it only took three seconds to pass through the 25mm block, not the 10 seconds that it did before.

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And here are those two results. This was the one that took 10 seconds.

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And this is the one that took three seconds.

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Now you may or may not be able to see that there is a significant difference in the diameter of this one compared to this one.

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A much smaller beam and a higher concentration of intensity.

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And that is why we were able to burn through quicker. This is still not focused because the focus is down here.

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It’s just a smaller diameter start point.

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And that really is the whole essence of what cutting is about.

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And then when we change the focus and reduce the diameter of the beam to an even smaller entry wound.

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Look how quickly it runs in. And now we move the focal point even closer.

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Now you can clearly see the difference in the diameter of the entry points of these beams.

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Slow. Faster. Very fast. Okay, now look you can see what we’ve got here.

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We’re getting more of a parallel beam.

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It’s tapered here, very tapered here. But here we’ve got a parallel beam.

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This is beginning to get much closer to what we see with a deep cut, a parallel cut.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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Look what we’ve got at the top here, though. You see, that’s the effect of the blue zone creating a cone at the entry to the cut.

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So we got some of our medium power doing damage.

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The higher the intensity, the faster the damage can be done. And here is a classic example of that. The speed at which damage is being done,

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is all to do with the concentration of that energy by the lens. Decreasing the diameter of the beam through a lens towards

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its focal point, gradually reduces the diameter of the beam and increases the intensity at the centre of the beam.

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We started off before the lens with this nice Gaussian distribution, we start putting these various intensities of light through the lens,

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and all of a sudden we get some sort of strange filtering effect down here, as you can see as we get closer to the focal point.

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Now, this is not a focal point of image.

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This is a focal point of intensity because we’ve got lots of different intensity focal points sitting in this beam. When we sample across

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there, is no longer a nice Gaussian distribution.

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Effectively, what we’ve done there, we’ve pushed the yellow up here like this because it’s intensified.

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The red beam is out here somewhere.

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Virtually useless and the blue beam, we’ve will actually change the shape of that

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gaussian intensity to something completely different than what it was when it started out.

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We’ve actually intensified the centre part of the beam itself, and we have filtered out or decreased the useless part of the beam.

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That’s what this lens has actually done with the aberration effect.

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So let’s take a look at what’s actually happening just here.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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Because remember,

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the yellow zone is not not just a zone. It is an area where the intensity is gradually going up and up and up towards the centre of the beam.

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Like that, so the center of the beam is still much, much higher than the edge of the yellow zone.

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This is the entry point. This may be only 0.2 of a millimetre diameter.

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The beam is coming in here, but this is effectively the intensity zone.

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The yellow intensity zone of that beam, which has been grossly amplified.

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Now outside this zone, we’ve got our blue zone.

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And outside that. We’ve got our red zone. Now our

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red zone is going to have no effect on our material because it’s such a low power to start with and it’s diverging and becoming even lower.

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So it’s intensity is unimaginably small. It’s never going to exceed the damage threshold of the material. The blue zone,

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well, given enough time. It may well have an effect.

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But the first effect that’s going to happen. Remember back to the pictures a few moments ago, the smaller we make the entry wound, the faster

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the damage will occur. So we’ve decreased this damage zone to very, very small proportions.

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So any intensity that happens to exist at that point is going to have a very, very rapid effect at damaging the material.

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And so consequently, what we’re going to get, we’re going to get the beam,

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which remember has still got a Gaussian distribution because we’ve not messed around with the yellow part of the beam specifically.

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That is still going to have a very high intensity path to the centre of that beam.

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Which is immediately going to rapidly grow down into and through a piece of material.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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So the only part of the beam that is going to have an effect is the bit that can get through the hole that’s made in the material.

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So the material is actually going to be a filter for all this other crap that you normally imagine is going to have an effect on your hole.

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No, it’s never going to get through the hole. It’s going to be filtered out by the surface of the material itself.

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OK, so this beam that you imagine happening below the focal point is never going to get there.

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The only thing that’s going to get below the focal point is what gets through the damage hole that you create on the surface.

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And the smaller the damage hole, the faster the material will erode.

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So this damage, technically this damage could only ever be as big as this beam.

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So the front of the beam might be pointed. But actually, if you give it enough time.

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The whole of that beam will produce a parallel hole.

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And if you stop the beam just before the material has finished, you will see that the front of the beam will still have a small taper on it.

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And that’s what we saw when we looked at our piece of, when we looked at the cut passing through our 10 millimetre material.

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Just at the bottom of the cut, we could see evidence where the beam had not quite passed through the material.

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We needed to give it a few more parts of a second to allow it to pass through cleanly.

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Now, by the time, you give it enough time to pass through the material,

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what will have happened is, some of this blue will have had an effect at the top here.

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Okay. And what will happen is this blue will effectively be doing this.

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It will erode. The top of the cut.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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So there’s your cut profile now. It’s a mixture of a little bit of blue beam with a lot of yellow beam,

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which has produced a parallel hole as it’s wandered through the material.

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So that’s how cutting, that’s what the cutting mechanism is. And your imagination about what’s happening below the focal point…

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It’s just totally misleading you.

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Now you can go and have a look at a lot of these tests that I’ve carried out, a lot of these experiments on my RDWorks learning lab channel.

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Now I carried out lots and lots of tests with lenses to try and establish what was going on.

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And one of the tests that I carried out was here. It was, it was basically a, what I call a speed test.

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It’s characterizing the beam itself. What we did, we put a thirty eight point one lens correctly focused onto the surface.

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And here we’ve got a two millisecond burst of power at 100 percent. Four, six, eight, 10 milliseconds. 12, 14, all the way up to about 30 milliseconds.

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As the exposure time was increased, you could see the rate at which the beam was growing.

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But if you look carefully, you’ll see that across here. There seems to be almost like a neck.

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But we’ve also got this strange ballooning effect which gets greater, more ballooning as time goes on.

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This is not uniform intensity, even at 0.2 diameter, and we’ve still got rays that are coming in.

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Like this? And like this.

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OK, they’re still not absolutely parallel to the axis.

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There are rays that are very slightly off axis, and they’re still passing through this 0.2mm diameter entry hole.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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OK, so the bore that’s been left behind by the major part of the yellow beam is being scoured

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by some more rays that are able to get into this hole through the entry diameter.

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These are rays that are very, very close to the centre and will come down here like this and they will produce a sort of a scouring effect.

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Which the more time you allow, the more effect they will have.

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Who said cutting was simple? Did I say that earlier on?

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That is the way that cutting takes place. That has got nothing to do with your imagination,

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which is dragged around in all directions by these pictures that have been out there for many, many years.

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These do not take into account the intensity of the beam.

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These just are rays and as I have shown you, these rays are totally ineffective.

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They don’t do anything at all. The only bit that works is the central part of the beam.

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Now it took me a long time to work out how lenses work,

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and I spent a great deal of time doing tests with lenses to try and reverse engineer what was happening to the beam.

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Acrylic is a fantastic material that leaves footprints in the sand.

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Can I read those footprints in the sand and find out what’s actually happening?

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Well, the answer is finally, yes. And I’ve tried to describe that process in this session.

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All the test data that I’ve collected about various types of lenses are included in this very, very long PDF document.

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It’s 109 pages long. Now, that isn’t 109 pages of reading, because although there’s a little bit of text there, we’ve got summary graphs.

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So we’ve got a whole range of lenses, a whole range of different set up configurations that I’ve used for the following tests.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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Now, although, as you can see from the crosses, it’s a pretty comprehensive spread of testing for lenses.

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Not every lens is in there. Now, as I pointed out to you earlier on, there is no such thing as a focal point.

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The focal point depends on the speed. It depends on the power and one of the things that surprises people.

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It also depends on material. So we’ve got a whole range of material here and a whole range of different focal

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points that happen to have the best focal points for different materials.

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OK, now it clearly says in this that these are tests using acrylic. Now acrylic cuts fairly slowly.

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If you want to cut MDF or HDF, the speeds are about the same as the speeds that acrylic cuts at.

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The only other materials that you can really cut are organic materials, which are the woods, the real woods, not the plastics.

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So real wood will cut at about twice the speed of acrylic.

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This one, which is a gallium arsenide meniscus lens.

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It takes two four six eight, maybe 10.

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And yet when we turn it the wrong way round. Two, four, six eight.

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It’s faster. So that’s the sort of information that you can read in this, immense set of data that I’ve produced.

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So there’s a huge amount of data that you can find out from this document. Look, here we’ve got a thirty eight point one CVD.

Transcript for Laser Cutting: Where Do We Start? (Cont…)

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Look how thin the entry is, it’s deep as well.

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So this is a very good lens for cutting deep and producing thin lines.

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Because if we take a look here, look, the lines on the surface are bigger, even though the cut is smaller.

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All right, so it looks like a thirty eight point one CVD lens has really got the best cut, the deepest cut and the thinnest entry.

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So the thinnest line, so you will be able to download this from the website.

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Well, that’s as much as I can tell you about cutting at the moment. We’ll get on and do some real cutting in the next session.

Transcript for Laser Cutting: Where Do We Start?

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Last updated August 26, 2021

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