15 – Fiber Laser Marking Machine: A palette of Sparkly Colours (39:04)

0:01welcome to another fiber laser Learning Lab I think we’ve been quite successful in trying to find out how these colors

0:08actually exist what causes them how they come about and how we can generate

0:14different textures on the color those that are smooth tend to be very light

0:20sensitive and those that have got a texture to the surface like those that

0:25you can see on the top row there they’re much more durable you can see the colors

0:30in many different directions so they do change texture depending on the way the

0:36light catches them but they’re not the sort of things that disappear to black now my definition of a production color

0:42something that can be created quite quickly most of the colors that I’ve seen being produced have been these

0:50smooth colors which are lighter sensitive very very fine pitch and very

0:56very slow speed that in turns means they take a long time to cover an area with a

1:03color my aim is to try and find ways of producing the color quickly and durably

1:09just as an example here we’ve got a gold just there at 3 it’s 2,000 millimetres a

1:17second and 1 micron pitch to do that little square probably takes 4 or 5

1:23seconds this one at the bottom is exactly the same color not quite as

1:29sparkly but it’s certainly a production worthy Gold which probably takes less

1:37than half a second because it’s done at 60 microns pitch and two thousand

1:44millimeters a second with a 30 nanosecond pulse I’m getting the feel

1:51for the way that these colors operated there they are in a way very temperature sensitive but not sensitive to the

1:58atmosphere but sensitive to the temperature that you can induce into the surface with pulses and power so I’m

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

2:05getting quite a warm cuddly feeling about being able to create these colors

2:13so from my experience so far what I’ve done I’ve actually put I’m producing

2:20what I would call a color search it’s a prospecting swatch which allows me first

2:26of all I’ve decided that the range of colors that I’m looking for are going to be sparkly colors in this range I’m

2:32around about 1,200 to 2,000 two millimeters a second and I also know

2:38that it’s very likely that the colors that I’m going to be looking for are roughly between four microns and one

2:44micron they may be down at 0.5 of a micron but I’m not going to be looking at that at the moment we’re just going

2:50to do a prospecting search between these two microns and these two speeds and

2:56we’re going to do it for every single pulse width now to be honest I got to

3:03the bottom of this page here and we got as far as 30 nanoseconds pulse and if we

3:10look at these results again you’ll clearly see that once we got to the end

3:15of this column here we almost ran out of color there is no color in these second

3:23and third rows here in the B’s and C’s so b1 was the end of the six known a

3:31second pulsus that’s where our color stops I ought to be just looking in the two four and six down a second polish

3:38region for the colors I did push on to the bottom of the page because hey I like things to round off nicely this

3:44here was the bottom of hide page 30 nanoseconds 1200 millimeters a second

3:50with a 1 micron spacing now that gave me a very nice really nice matte black but

3:58then all these other colors here there’s no color in them so when I arrived at this point here with a 30 nanosecond

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

4:06pulse 1200 kilometres a second and a 1 micron line spacing I got dead jet black

4:14very nice but I’m already getting the message Hey there aren’t any more decent

4:21colors to be found at this end of the range there’s no point in increasing the pulse length anymore all

4:26do is finish up burning a hole through the material if I’m not careful so let’s stop at this point and consider whether

4:32or not there is something hiding below this black well I mean below this black

4:38can we reduce the power on this black patch and find some color well there are

4:44two ways that we can reduce that the power into that black patch this is done at 1200 millimeters a second so the

4:51first thing that we could do is increase the speed which decreases the number of dots horizontally the next thing we

4:58could do would be to increase the pitch from one micron to 10 microns so this

5:04one is 10 microns and two thousand millimeters a second so we’ve significantly decreased the number of

5:11pulses per square millimeter and we’ve changed it from black to dark brown okay that’s very good let’s let’s

5:19see what else we can do we can’t change the speed anymore because we’re really running maximum speed ie we’ve got the

5:25minimum number of dots across so the only option left for us now is to increase the line spacing so here we’ve

5:31increased the line spacing from 10 to 20 microns hmm it’s improved it a bit it’s

5:39turned into a slightly lighter brown just a bit of a almost like a pale gold so let’s go one more step and we’ve

5:47taken up to 40 micron spacing we’re getting a little bit better gold now and

5:53here we are at 60 microns spacing yes 60 microns that’s one beam width and we’ve

6:01got a lovely gold you know at the end of the last session I showed you the pattern for what looked like a matte

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

6:08black but this one is not going to fall your eye this is exactly what it looks like matte black this is done at 90

6:16kilohertz so now with the speed at 2000 filmy is a second you can actually see

6:22the pulses this is the line that created this pattern up here this is the last

6:28line just here where my finger is so let’s just go and have a look at this pattern I’ll just move that up off the

6:34screen ok the contrast changes I mean there’s no doubt you can see that the general background there is black

6:39but what are those little white pieces well it’s zooming have a look because these are little blobs of stale so go

6:46we’ll gradually raise the table up and bring the top of these little elements

6:53here into focus just there now that’s

7:00120 let me raise it up by 20 microns 40

7:08microns 50 60 microns and we’re still

7:14not at the bottom of the pit yet 70

7:19microns 80 microns

7:30just about there somewhere around about 82 or 85 microns that is a very very

7:39rough surface let’s go down a further

7:44magnification

7:49you can see the last line here and you can see the wake this rubbish has

7:57created on either side of the line sitting here so as we move up so we’re leaving these little wakes of globs of

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

8:06Steel which is sticking up above the background thought you might be

8:11interested because this all helps to paint a picture of where color comes

8:17from in this particular instance we’re seeing no color even at this level but

8:23sometimes you can see color and you still get black but I’m going to have to

8:28investigate all these lower powers but particularly the ones here in the 2 4 &

8:346 known a second region because they’re the ones where I think I’m going to discover the colors that I’m looking for

8:41this next bit is going to be a very tedious task for me I’m gonna have to sit by the Machine and I’m just gonna

8:47have to play with a few factors I hope to do it in a fairly logical way and hope that at the end of it we should be

8:53able to produce a nice palette of colors so I’m off to do quite a few hours worth

8:59of work and I’ll come back and report to you when I’ve got some interesting results this is a tedious job but it’s

9:06fascinating I said that wasn’t gonna

9:11involve you and I’m not going to involve your great deal but I thought you might

9:17like to see a little bit of the method or procedure that I’m going through to

9:22try and get these colors because I’m got I’ve got a little bit of an intuitive

9:28feeling about where these colors are and how I can get them now and I’ve got a list here so far of about 14 colors that

9:35I’ve identified nice clean crisp colors that I think we should be able to use if

9:41we want to do some artwork I’ve still got a lot of colors to add into my palette but slowly slowly with building

9:49this list for example oh look at my a3 swatch and I say that’s quite a nice

9:55sort of maroon color dark purple start off just there and see how we can

10:03develop from that color so d3 800 millimetres a second with the 20% power

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

10:10and the pilot mode 30% so I’ve actually increased the power to get a lighter

10:15color on this swatch now I’m sure you can see in this light that that is a very dark maroon and underneath it we’ve

10:23got a slightly lighter dark purple and then we go on to a sort of a Apostoli

10:29color here which is a a lilac e pink that color there is only skin-deep

10:37it is only manipulating the oxide layer the mop the molecules in the oxide layer

10:44and changing their colors the colors I’m looking for are disrupting the surface

10:50of the metal underneath as well and I’m producing a texture that’s what gives me the sparkly effect now the current range

10:57that I’m going to be finding will be probably significantly different than

11:02the range that I could find if I was looking for these superficial surface colors now the surface colors are what

11:09everybody else is looking for and everybody else is identified eventually I’ll probably go back and try and track

11:14these down as well because there’s probably a much wider range of colors to be found but that’s not my first task

11:22because they take so long to produce they’re very very slow they’re not what I would classes production colors and

11:28the whole point about this is you want to use these colors for something it shouldn’t just be a gimmick to sell the

11:34machine we’ve gotta first of all try and recreate d4 and that’s my starting point

11:40it’s completely repeatable ideally I’d like that color to be sparkly and as

11:48dense as that so here are my starting parameters 800 millimeters a second well

11:55I know I’m not going to get sparkly colors at 800 millimetres a second I need to be a thousand or 1200

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

12:02millimeters minimum to get sparkly colors so if I change that to 1200

12:09millimeters a second this is this is less of a predictable thing I don’t know whether their power

12:15is linear or not when I’m using for nanoseconds I know that I’m using a

12:21frequency of 500 kilohertz so the kilohertz is fixed therefore the

12:29only variable that I want to play with is the number of pulses per square

12:35millimeter as I increase the gap between the lines I’m reducing the power and as I reduce

12:42the speed I’m increasing the power using this little general rule about pulses per square millimeter provider don’t

12:50fiddle with any of these factors here what I can say is look I’ve reduced the

12:56pulses per square millimeter horizontally because I’ve increased the

13:01speed and I’ve increased it by better third what I ought to do is to decrease

13:07this by a third so really to take this down to something like point zero zero

13:15zero six so I’ve gone faster on the speed and and smaller on the pitch net

13:23result is it’s probably still going to take quite a long time to produce this color but I might be able to make it as

13:29a sparkly color now because you know I’m playing with the same numbers the same nerve repulses roughly the same number

13:35of pulses per square millimeter okay well that was reasonably successful wasn’t it considering I’m not using a

13:40calculator I’m just guessing what we’ve now got is 1200 millimeters a second that’s the age of my sparkly region

13:47problem is we haven’t got a sparkly finish because the pulses are seriously

13:54limited because we’re only using 30% power so all the spike enos of this

14:00sharp pulse is not there so we’re doing very little damage to the surface of the material that we need to do is now push

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

14:07the percent power up now if we push the percent power up we’re going to change

14:12the color now this is where I say percent power is a difficult thing to play with while I’m just playing we pick

14:18pulses per square millimeter as you can see I can really easily guess what’s going to

14:24happen as soon as I start messing around with the power mmm I’m joking off the

14:30edge of the cliff and I don’t know what’s at the bottom let me put the power to something like 50% to make the

14:38pulses sharper it means I’m putting more power into the job now there are two ways to get rid of the power number one

14:45I tell you what we do we’ll leave it at 50% and I’ll show you what happens well

14:52there we go that’s what’s happened we’ve produced a lovely sort of like pink lilac e color now of course what you can see here with

15:01the previous two calluses they’re not as bright because when you turn them to the

15:07light they’ve got this surface proper look they disappear you can only see

15:13those colors in certain lights but look at the move at the bottom as I turn them

15:19over and it’s remaining there’s a slight change of colour there but we’ve now

15:25messed around with the surface texture that’s by increasing the power to 50%

15:31okay so now we’ve got the texture of the surface there what we’ve now got to do

15:36is try and get the color back now what we’ve done we’ve increased the power so

15:43now we’ve got to find a way of decreasing the power and there are two ways that we can decrease the power first thing is we can increase the speed

15:51now we know that increasing the speed is only going to make it more sparkly from

15:561,200 let’s go it to 1600 and see what effect that has now hopefully that’s

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

16:02going to bring us bring the color back down closer to these darker colors let’s

16:10give that a try so that didn’t work quite as planned we didn’t finish up with the darker mode

16:16we finished up with a latte coffee color it’s a very nice color which I shall

16:21have to make a note of on my palette and instead of changing the pulses

16:28across which is what the speed is doing we’ll try and change the pulses vertically in the y-direction by

16:35changing the pitch so we’ll change the pitch back from six tenths of a micron

16:42to one micron and see what effect that has so we went when we went from 1,200

16:50to 1,600 millimeters a second we reduced the power so much in the horizontal

16:56direction that we caused the coffee color so what we’ve now done is we’ve decreased the speed in the horizontal

17:04direction to increase the number of pulses again but this time I’ve offset

17:09the increase in pulses in the horizontal direction by decreasing the number in

17:15the Y direction by increasing the pitch from 0.6 of a micron to one micron and

17:23we’ve got our move back again so if I reduce the power even more can I get

17:30back to a darker move and the way that it looks as though I’ve got to do that is by changing it in the vertical

17:36direction and not messing around with the speed so I leave the speed at 1200

17:41and this time will change to something like about 1.5 microns it’s only going

17:47to be a small micron change to affect this quite dramatic change in the amount of heat that we’re putting into the

17:53surface well we’re losing our color again and we’re going back to a sort of a latte color so I can’t change the

18:00color the way that I want it to change by decreasing the pitch let’s change it

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

18:07the other way just in case well we are getting it back again let me take it

18:12right the way down then to something like about zero zero zero two point two

18:19of a micron that’s a silly a number let’s see how dark I can get it look even down at two tenths of a micron it’s

18:26made no difference to the color can I take the speed up and change the color

18:32now and 1400 is taking us towards pink

18:38Brown so let’s go down to a thousand that’s a long way back eight hundred and

18:46stubbornly refuses to change color but what it does demonstrate is the huge

18:53range of parameters over which you can find these colors we’ve put that nice

18:58latte color in our color swatch I think we ought to have one of these nice lilacs in there as well all I’ve got to

19:04do is find out which one of those was the fastest that’s the process that I’m

19:09going through very tedious but I’m enjoying hunting for these colors as you can see I can chase these colors around

19:15by just understanding how the colors come about the amount of heat going into

19:22the surface here we’ve got a couple of dark purple or maroon colors which are

19:28not sparkly colors so I can’t actually get these colors into my sparkle range

19:35but they have proved very very useful in telling me something about the way these

19:42colors are produced and the way this machine works now in the easy CAD software just here I have the option to

19:50change the way in which scanning takes place I’ve got I think five options

19:58we’ve got this one here which scans backwards and forwards and also joins up

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

20:05the ends of the scan lines we’ve got this one here which looks as though it

20:12might be an intermittent scan I don’t really know because I haven’t looked it

20:19up in detail we’ve got another one here which is a unilateral scan which means

20:26that it only scans in one direction and the red lines indicate the flyback lines

20:32to the beginning then we’ve got this one here and the red lines on the end

20:39indicate the fact that it flies from one end up across

20:46across up when the ups are not included in the cut it’s only the backwards and

20:52forwards bi-directional scanning which are included and then finally we’ve got

20:59this funny one which is a circular one which is a really strange one and I don’t know why you’d want to use this

21:04because I’ve got an idea that it gets that the actual beam gets slower as it

21:09gets towards the center but whatever is we have got these five different scanning options and only that one I

21:17think as a usable scan the unidirectional scan you can see the

21:22strange color marking on this top pattern here it almost looks like a graph that’s the bi-directional scanning

21:30the one underneath which is the nice uniform pattern is the unidirectional

21:36scanning this one here is the dotted

21:41line scanning this one here is one of those it’s got the joined up ends and

21:48you might not be able to see that very easily but there are basically little diagonals little dark diagonals that

21:55come out from the center and the centre itself is dark that’s the spiral scanning so of the

22:00five scanning possibilities that this machine offers only one of them looks as

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

22:06though it’s going to be suitable for using to try and track down in the colors now I have been using both the

22:12bi-directional and the unidirectional scanning and it has probably accounted for some of the strange results that I

22:18have been getting now as I’ve mentioned to you before there is no exact formula

22:24for any one color there may be a range and some of the colors that I’ve discovered have got huge range of

22:32opportunities you’ve heard me mention several times that I’m looking for what I call production colors now production

22:38color to me is something that can be done quickly and efficiently with a good stable color and not one of these colors

22:45that you have to look at in a certain light to see what it’s really like to make bought to make things a little bit more accurate in my comparison I’m going

22:53to run a ten millimeter by ten millimeters and this will tell me how long it takes to engrave a hundred

22:59square millimeters

23:11so that’s about 66 67 seconds okay so I’ve loaded another set of

23:17parameters in here and you’ll hopefully spot something quite significantly different this time apart from the time

23:31but slow there wasn’t I it was about four and a half seconds bit different 66

23:36seconds isn’t it now we can move those goals around in all sorts of lights as you can see and they do change in

23:43texture a little bit but you however you look at them you can see that they are gold whereas some of these other colors

23:50on here disappear to black well we’re

23:56back in the office now because after several hours in the cold workshop producing lots and lots of color

24:01swatches it’s always interesting because I’m learning a great deal about where these colors are coming from and how you

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

24:08can chase them around a little bit and how you can modify them now we’ve just come off of talking about how some of

24:13these colors are very fragile look at that lovely salmon pink and Moe they’re

24:19fantastic colors provided you look at them from just the right angle you move

24:25it slightly and they almost turned to black they lose all their colour that’s

24:31what I define is a fragile colour now something that I have discovered which

24:36undoubtedly other people already know is that we’ve got these two colours here

24:43and decide them we’ve got a plus and a minus but they’re not really plus and

24:48minus because what I discovered was that if I do a single scan which is what the minus means it means a scan in that

24:55direction then I get this salmon pink but if I use exactly the same parameters

25:01and I change my scanning technique to a double scan it scans across to start

25:07with and then vertically I get a different color so I’m modifying the

25:12surface film by doing the thing twice if I scan across it this direction twice I

25:19don’t get that color but if I scan it in the opposite direction I get a completely different color the

25:25difference is that the single scan this one takes one minute 39 seconds to produce a hundred square millimetres

25:31this one takes three minutes six seconds which is more or less double the time to

25:37produce a group reached a point where I think we ought to sit down and summarize

25:42what the goals this project our because I could spend hours and hours chasing colors around on

25:49bits of stainless steel it’s fascinating I’m learning a great deal but I have to

25:56stop and say how do I know what I’ve achieved a goal I haven’t even set any goals I need to

26:03put boundaries on where we’re going to go now we’ve just seen with the two gold examples how one was done quickly and

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

26:11the other was done relatively quickly you could view them in different lights and they would still look like gold on

26:18the other hand there were other colors that we talked about which were I think I used the word fragile which meant that

26:26they they were lovely colors provided you looked at them in the right light from the right angle so what I’ve done

26:33I’ve sat down and worked out a quick ranking table for how I would judge a

26:39color can it be viewed in different lights and still maintain a reasonable

26:46semblance of the color that you thought it was and be can it be produced

26:51cost-effectively the realization of this came about when I started to do these examples this here

26:59took one minute 25 to produce this one took one minute 48 still reasonably fast

27:11this one which I never finished was already about 30 or 40 minutes in before

27:18I decided to abort it because it was going to take an hour and a half to make me two hours to produce this now as I

27:25was messing around with these small swatches I realized that there was a difference in the time taken to produce

27:30some of them but I wasn’t putting any quantifiable data down that enabled me

27:35to say yeah this is rubbish or this is not rubbish so that’s what I’m about doing here with my ranking table a

27:42b-grade color is something that it may not have the widest viewing angle and it

27:48might not have the widest color tolerance but it’s reasonably durable and it can be deposited in

27:56when I say a reasonably cost-effective manner these are very all subjective

28:01judgments I have now settled on 10 by 10 millimeters which is one square centimetre hundred square millimeters

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

28:08for the standards and not only am i logging the parameters I’m also logging

28:15the time taken to do the one square centimeter you’ve got to choose a number

28:20for yourself what is cost-effective for you but when you’ve got a twenty thousand pound machine I would have

28:27thought that if you’re spending more than a minute to do a square millimeter it’s not really cost-effective that’s

28:34just me speaking as an X production engineer you know I want things to happen quickly and efficiently so

28:41anything that’s a C and a degrade color is out the ballpark as far as I’m

28:46concerned C grade colors may be very very pretty but they will have a very narrow viewing angle as we’ve just

28:52discussed they they’re not very durable two different light sources you know

28:57different colors in different lights and they can’t be done in a cost-effective

29:03time okay so now I’ve got a white LED light that I’m shining on them

29:10nice colors aren’t they hang on that was a nice pink a few minutes ago that’s now

29:17looks almost like an orange now so let’s just change the angle of the light if I can there we go

29:24there is a very a very much suppressed range of colors in LED light it’s very

29:30white there’s not much red or orange in it so what we’re picking up has a

29:37completely different sort of reflected color range depending on the light that

29:43we use to view these colors in ideally we’re looking for colors like this which

29:49regardless of how you look at them in the light most of them remain pretty stable we’ve got one there that he’s not

29:56you’ll see that changes color dramatically as I look from gray to black and then when we shine LED lights

30:03on it they’re still pretty much the same

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

30:08they’re gold and Silver’s and then we’ve got basically degrade colors which is the worst of everything very poor viewing

30:15angle very poor tolerance the light takes an age to produce most of the colors that we’re going to come across

30:20that I want to know about our eyes and bees there are certain strange

30:26properties happening when you do crosshatch it’s been a revelation because it means that I can go quite

30:32fast I can get some quite amazing durable colors with cross hatching an

30:38ivory color on here is a durable a grade or B grade color because we’ve got this silver here which is basically rubbish

30:45it’s a serie degrade got a lovely gold here which takes 3.9 seconds to produce

30:5010 square millimeters now that’s a pretty good deposition rate and that’s a production color as far as I’m concerned

30:56we’ve got another gold here which takes a second longer for 0.8 seconds so okay

31:02so it takes 25% longer we’ll come back and look at the difference between these two colors under the microscope in a

31:09minute because why would I use one in preference to the other this is a

31:14slightly brighter lighter gold and maybe this has got a slightly better light durability I mean when we get down to

31:21here for example we’ve got these Browns these these matte Browns look eleven point six fifteen point four twenty

31:28three point three they’re all the same parameters except one was done with the 20 minute 20 micron spacing one was done

31:35with a 50 micron spacing am almost done with a 10 micron spacing okay so that’s

31:41the reason why we’ve got greater times as I close up the lines it takes more time to scan the same area but there is

31:50no difference in quality so why would I go for 23.3 when I can have 11.6 now

31:57black is a particularly difficult color you can’t get a decent black without

32:02spending time on it and yeah okay so this took 34 seconds to produce that

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

32:09black. Black as a color you might want to steer clear off unless you’re absolutely desperate. So it would appear that golds

32:16and Silver’s and whites are the colors that you can go for. So let’s just take a quick look at this caliper

32:22here we’ve got these pinks and rubbish colors down here which lovely but

32:28they’re not they’re too fragile they’re not production colors and they also take one minute thirty nine three minutes six

32:36minutes I mean even these lovely Pink’s down here the one lesson that I have

32:42learned is look we’ve got two blues that are exactly the same and we’ve got two

32:47Pink’s at the bottom here that are exactly the same the difference is time. It would appear that I don’t need double

32:55scanning if I produce a rough surface in the first pass but I can’t get those

33:00colors faster that’s part of what I’ve been trying to do find a color and then

33:06see how far I can push it in terms of speed and still retain the color some

33:12colors you just can’t get the speed out of and that demotes them to possibly a

33:19flea grade where the color is good it’s got a wide tolerance of light capability

33:24but it ain’t very quick that’s the difference between an A grade and a B

33:30grade color mainly the amount of time it takes to produce them. So we’re gonna close the session with a few minutes of

33:35looking at some of the colors under the microscope now this is the salmon color

33:40that we talked about a mixture of pink and yellow and the pink predominates but

33:46this you know this there’s probably 50% yellow in that picture with a hint of

33:51pale lion green but you don’t see any of that with the naked eye you only see the

33:58pink. The other thing that I want to point out here are these striations lines that you see on here you can see through the film to the material that’s

Fiber Laser Marking Machine: A palette of Sparkly Colours (Cont…)

34:05underneath now there is a bit of hint on there of lines going up and down that’s

34:11the scan lines because this is the second pass. So it’s got the lines are going vertically now amazing in that

34:18just one pass different then all of a sudden the surface texture has still remained flat but the color has changed

34:25because we’ve changed the thickness of the film that’s on the surface now we

34:30take a look at those two golds the first one was the slightly of the two golds the Mexicans know all

34:38those colors look at them they’re superb which had a scanning interval of a hundred microns so what we’ve got here

34:46is a beam width of 60 microns and another beam width of 60 microns so

34:53we’ve got 40 microns between which have not been touched well not entirely true

34:59because you’re gonna ask the question what are these marks across here

35:04these regular marks well that’s the first scan that went across but this is a crosshatch scan so if we look here

35:12carefully you might just be able to pick up the beam shape the striations for the

35:19beam shape going across there on this channel and you could certainly pick up the beam striations in this channel here

35:26look at the rainbow of colors on there and yet that comes out as just a sparkly

35:32gold now let’s compare that to that to the lighter gold this has only got 60

35:37microns spacing between the lines as opposed to 100 microns. Which is why it took a little bit longer and look here

35:44we can see the 60 microns here with virtual joints between the lines but

35:50again we’ve got our marks that run across here look that little mark there in that little mark there so there’s the

35:5660 microns for the first pass going across there so as you can clearly see there is not as much rate in this

36:03picture it is more yellow and some blues and greens and that accounts for maybe

36:10why visibly this looks a slightly lighter gold this is 400 times

36:16magnification and it’s not what your eye sees that’s 50 times magnification and

36:21even that you wouldn’t say is going to give you a nice bright gold. Now that’s really pretty isn’t it but that that’s

36:29the one that gives you the redder gold now this brings us nicely back to the

36:35 situation that I described very early on as to about how we came across these patterns. This could quite easily be the

36:43regular pattern that we saw on butterfly wings now it’s the regularity of that pattern

36:48that’s probably allowing us to see the dispersion of light in many different directions and it gives that color its

36:55durability in one of the earlier videos we’ve seen black before and sure enough

37:01is that black that should be a dark gold

37:07according to what we see here we’ve got our 10 micron lines but every time we

37:14move across 10 microns what we’re doing we’re leaving a debris trail that’s down the side of the burn so what we’ve got

37:22here is a series of plowed field effect type buildups behind the beam as it

37:29moves across finally we’ll take a quick look at my B grade pinks and blues as

37:36you can see we move in and out of focus to all sorts of things there it’s a distorted surface is broken up

37:44surface so that’s why it’s glittery we’ve got some pink in there but we’ve

37:50got a lot of dark green and yellow so the interesting question is why is this

37:56coming out such a nice bright glittery pink okay now this is our durable blue

38:02that takes too long to produce so it’s a bit grade we’ve got a scale on here

38:09which is naught to 10 microns now we’ve got a 4 micron pitch which we

38:17can’t see any sign of to be honest on this screen at all yeah we’ve got some horizontal lines but we certainly can’t

38:24see the 4 micron pitch so what happens when we put the second scan on top of it so we’ve got some predominating vertical

38:31lines on here there so there’s still no indication of our four or five micron pitch across this way and yeah it is

38:39still blue we’ve got a little bit more dark color in it this time bit more green but I think we’re the only shadow

38:47of a doubt you would believe that to be a blue and it happens to come out blue so you don’t always see what you get on

38:54this screen so I think with that pretty picture on the screen we will this session off and say thank you very

39:00much for your time and I’ll catch up with you in the next session