11 – Understand and Care for your Laser Mirrors (35:11)

00:13

Welcome to another Lightblade Learning

00:17

Lab. Today we’re going to be attacking

00:20

the subject of Mirrors, now this machine

00:25

works with mirrors and if we take a look

00:29

down here you see we have a mirror and I’m

00:33

shining a light into it and it’s reflecting at

00:36

you, now you will think mirrors as

00:39

something like this something nice and

00:42

shiny which if I bend it as you see we

00:49

get distortions and with our laser light

00:53

we get exactly the same thing we must

00:55

have a flat mirror

00:56

otherwise we get a distorted beam the only

01:00

thing is that a shiny mirror does not

01:05

mean a reflective mirror when we’re

01:08

talking about the infrared region

01:09

Shiny is great for visible light it doesn’t

01:12

have to be shiny for infrared light now

01:15

I demonstrated that to you in one of the

01:16

earlier sessions when we took a piece of

01:19

dull copper and found that it was reflecting a

01:23

very large percentage of the infrared

01:25

light that was fired at it i keep using

01:28

the word light because that’s what it is

01:30

but in reality as i showed you as well

01:32

it is heat, concentrated heat energy and

01:38

that’s what does the work with this

01:40

machine

01:41

so today we’re going to look at the look

01:43

at mirrors because mirrors have a very

01:46

special role in this machine. So here we

01:50

are at the back of the machine and we’ve

01:52

got the laser tube itself now the laser

01:55

two fires a beam of light out of its end

01:58

there and then it’s got to somehow turn

Transcript for How to Clean Laser Mirrors (Cont…)

02:00

around in the opposite direction and

02:03

arrive at this point where there’s a

02:05

third mirror which points the beam

02:08

downwards towards the lens which is the

02:11

bit that’s really doing the work so

02:14

let’s just have a quick look at how that

02:17

happens we’ve got one mirror here which

02:22

is sitting it roughly 45 degrees so the

02:25

beam comes out of here and

02:26

reflects off that mirror and travels

02:28

across the machine so here is the second

02:32

mirror

02:33

once the beam has turned the corner it

02:35

fires across the machine here like this

02:37

onto this second mirror and this second

02:41

mirror

02:42

regardless of where is on the machine

02:45

like this

02:47

the laser beam is hitting it and at 45

02:49

degrees it bounces off hopefully

02:52

parallel with this beam and arrives at

02:56

the cutting head. At the cutting head

03:00

we have yet a third mirror which is

03:02

sitting here and the laser beam comes in

03:05

here and bounces off that at 45 degrees

03:08

and then it gets directed downwards

03:10

towards the lens which is at the bottom

03:12

here where it concentrates the energy

03:14

and fires it out of the nozzle so three

03:18

mirrors are involved with the

03:19

transmission of this laser beam from its

03:22

source to its destination and that’s why

03:27

mirrors are very important every mirror

03:30

has got to be as efficient as possible

03:32

if we assumed the mirrors for example

03:37

are approximately let’s just say

03:40

ninety-seven percent efficient now that

03:44

might sound quite a high efficiency but

03:47

technically what that is that means it’s

03:48

three percent inefficient and if we’ve

03:51

got three percent loss at three mirrors

03:55

that’s ten percent nearly if we start

03:58

off with 60 watts

03:59

we’re going to finish up with 54 what’s

Transcript for How to Clean Laser Mirrors (Cont…)

04:01

here and then we’ve got a further loss

04:04

through the lens itself which might be

04:06

another two or three percent so we may

04:10

have as much as twelve percent loss

04:12

through the system now that’s quite a

04:15

large loss that you don’t really want to

04:18

exceed I mean those figures that I’ve

04:21

given you there are typical if they get

04:23

much worse than that then I think you’ve

04:25

got problems with the machine itself. I’m

04:27

going to be using two pieces of

04:29

equipment but what I’ve got here is

04:30

three pieces just to show you. To be able

04:34

to establish how much power the laser is

04:38

generating

04:39

and how much power is arriving at and

04:42

from each mirror you have to have an

04:45

instrument that measures heat because

04:48

bear in mind this beam of energy is heat

04:51

energy and there are several things that

04:55

we could use there are many different

04:57

types of power measurement meter on the

04:59

market

05:00

some of them very expensive and quite

05:03

accurate others are cheap and okay this

05:10

is a a cheap version of a power meter

05:14

which is actually quite expensive

05:17

I mean this is something in the region

05:18

of about 250-300 dollars it’s a american

05:24

manufacturer and it’s a very good

05:26

quality you can buy the same thing for

05:28

about a hundred dollars, i say the same

05:31

thing

05:32

it’s a Chinese copy and it’s not as good

05:35

but it’s adequate for doing the job and

05:39

here we’ve got my own version of this

05:42

which has got compromises but it produces

05:47

the same results as this within a watt or

05:50

two and it also does it a lot lot

05:54

quicker than anything like this it’s not

05:57

instantaneous it’s an average which is

05:59

what we’re really looking for. So

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

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that means that today although i could

06:03

be using this one this is relatively

06:06

speaking very slow to use whereas this

06:09

one is a lot faster i should be using

06:12

this because I’m an impatient person

06:15

the third thing that we’ve got here is

06:19

basically just a thermocouple it’s a

06:24

k-type thermocouple which in essence is

06:27

what buried inside here a k-type

06:29

thermocouple for measuring temperature

06:30

because what we’re going to be doing is

06:34

firing heat energy at this absorbing

06:37

surface and we’re heating this block of

06:39

metal up. Now if you fire energy at this

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block of metal for a fixed period of

06:45

time then it will heat up by a known

06:48

amount

06:48

and that’s the basis upon which we are

06:51

measuring the power of this machine the

06:55

amount of temperature rise that we can

06:57

generate in this small block of metal

07:01

now with this device the answer has been

07:05

scaled for us so that we get the readout

07:08

directly in watts with this system it’s

07:13

a compromise we get a reading of

07:15

temperature rise should i say and what

07:18

we have to do is we double the

07:19

temperature rise for the scale i’m using

07:22

and that gives us the wats so it’s not

07:25

terribly complicated

07:28

now as I probably have mentioned before

07:31

umm I’m gonna be firing a laser into

07:34

nothing and i personally don’t like

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firing the laser through down to the

07:39

bottom of the machine although my test

07:42

is running at full power

07:44

what will happen is I should be

07:46

collecting the power in this device so

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the power will not actually be coming

07:51

through to here and down there but if

07:53

for instance i had to stop then the

07:55

power will finish up coming down here

07:57

and this is just really a little safety

07:59

precaution this water will fully absorb

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

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all the energy and it will do no harm at

08:04

all it’ll take a lot of energy to heat

08:07

that water up but eventually it will

08:09

heat up this little device here hasn’t

08:12

really got a name it was difficult to

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describe when I first invented it, it looks

08:19

like a lollipop and I was going to call

08:21

it a lollipop

08:22

but then I decided it would make a lot

08:24

more sense to call it possibly an “O G ma

08:28

flip” a “whatsit” and in the end I

08:33

decided to call it as you can see that

08:36

second term there a doohickey, it’s a term the

08:38

Americans use for something that

08:40

really doesn’t have a description and so

08:42

this has affectionately become known as a

08:44

doohickey and I’ve got a program on here

08:47

which has been designed to make a burn

08:53

of 20.5 seconds, a very specific length of

08:57

time and so we’ll just load that program

09:00

In

09:08

and here’s what the program looks like

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it has a blue section up there which

09:14

runs from the center to the outside at

09:18

one millimeter per second and that’s 10

09:22

millimeters long so for 10 seconds

09:24

it runs at one percent power now one

09:28

percent power will not turn the later on

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so effectively I have 10 seconds to push

09:34

the button and do anything I like before

09:38

the test actually starts and then the

09:40

test starts and it follows this spiral

09:43

pattern so that the beam does not stand

09:45

still in any particular spot on here at

09:48

a given point in time

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that’s if i’m going to be leaving it

09:51

sitting still but most of the time I

09:53

should be moving around manually in

09:55

front of the beam as you’ll see and that

09:58

runs for 14, it runs at 14

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millimetres a second that pattern lasts

10:05

for twenty point five seconds

10:07

mmm one important feature that you must

10:10

have when you’re using one of these

10:12

power meters is a bucket of water not

10:15

because there’s a fire risk but because

10:18

you need a bucket of water which is

10:20

basically room temperature this bucket

10:24

of water has been sitting in here for

10:26

several weeks and it’s got the same

10:28

basic room temperature as this workshop

10:31

and it’s important that every time you

10:34

run a test you start from the same

10:37

temperature give or take a degree or so

10:43

so I’m going to start this off by waggling it

10:48

around in there and finding out what

10:52

temperature it’s stabilized at. It looks

10:57

to be about nine and a half

10:58

degrees

10:59

well whether it’s nine and a half degrees

11:01

ten-and-a-half or 11 degrees is not too

11:04

critical but it mustn’t be 15 or 20, so

11:07

within a degree or so is what we’re

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looking for and now we make sure that we

11:13

dry the probe off and i always start

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with the meter off. We’ll go round to the front of

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the Machine and we’ll start the program

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off you can hear the machine is running

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the power is not running because the

11:31

tubes not lit, and now i’m going to stand

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here. I’m gonna put the power on and i’m

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going to put 9.4 and now i’m going to

11:39

put this in front of here

11:45

as you can see I’m moving it around so

11:48

that I collect the power evenly over the

11:50

surface

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test done

12:07

thirty-seven point two so that’s the

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maximum value and our starting temperature

12:15

was 9.4 running the machine at sixty-seven

12:20

percent power which is supposedly should

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be giving us 60 watts so let’s have a

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quick look to see what had the mass

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works out 37.2 37.2 minus 9.4

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equals

12:46

27.8 x 2 equals 55.6 well that’s a bit

12:55

down on expectations so the tube is not

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delivering now what it was when i tested

13:03

originally so we’ll repeat the test the

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temperature rise is 37.4 minus 9.7 which

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is start point because 27.7 x 2 equals

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55.4 so we’ve got a reasonably

13:30

consistent result coming in there, so

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coming out of the tube

13:34

we’ve got 55-point ish…. now you

13:38

remember that we made this little device

13:41

this is quite a handy little device

13:43

because what it does is it shows me

13:45

approximately, once it bounced off this

13:47

mirror 45 degrees it’s going to come out

13:50

here so this gives me a nice idea where

13:53

the laser beam, where the laser beams

13:55

coming out, so we run the same test again

13:58

but this time we’ll do it after the

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mirror. So we’re starting off at 10 degrees we

14:05

finish up at 35.3

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well it doesn’t take a mathematical

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genius to work out the differences being

14:17

25.3 we double up and that’s 50.6

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so we basically lost five watts across

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that mirror five watts out of 55 that’s

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ten percent across that one mirror give

14:37

or take points here and there now that

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is horrendous

14:41

why? Is it the quality of the mirror?

14:45

Shouldn’t be because these are Molybdenum mirrors

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and molybdenum mirrors

14:48

typically are about 97 or 98 percent

14:52

efficient this one appears to be ninety

14:55

percent efficient

14:56

ok let’s try something should we? Thinklaser

15:01

were very kind and provided me

15:03

with a case full of pieces which basically

15:05

is a lens and mirror cleaning kit so

15:08

let’s take a look inside. We’ve got two

15:10

chemicals in here

15:12

one of them is isopropyl alcohol and the

15:17

other one is acetone well isopropyl

15:19

alcohol is mids…

15:22

it’s quite a gentle cleaning agent and

15:25

it dries off very quickly but acetone is

15:28

a lot more aggressive but a great

15:31

material if you want to do a fairly

15:34

substantial clean on the mirrors now the

15:37

mirrors are not as sensitive as the as

15:41

the lens and so because these are

15:44

molybdenum which is a very hard metal we

15:47

can be…., when i say aggressive, I don’t mean

15:52

we can go at it with a hammer but

15:54

acetone is not likely to have any

15:56

serious effect on the surface finish so

15:59

I’m going to take a cotton wool bud and

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

16:01

we’re going to have a go with the

16:04

acetone and cleaning the surface of the

16:07

mirror itself now all i’m going to do is

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to rub it

16:13

with the cotton wool bud

16:19

and give it a good clean the surface to be

16:22

honest the surface is completely shiny

16:24

there is and there is if we look

16:28

carefully we might see just a small

16:31

amount of brown staining on there just a

16:35

small hit nothing serious so we take a

16:41

little bit of something off the surface

16:42

let me do it again with the other end of

16:46

the cotton bud and see whether we can

16:47

get any more off. As you can see I’m not

16:50

being particularly gentle with this i’m

16:52

being quite, giving it a quite good old scrub

16:55

and again we are getting a little bit of

16:59

discoloration on the bud so it’s still

17:02

not completely clean

17:04

let’s use the other side of the bud

17:07

see what else we get, let’s try another

17:08

completely clean but now we don’t have

17:11

any coloration on there at all

17:13

so whatever was on there is not any more

17:17

now to make sure we get consistent

17:19

results we’re going to take another set

17:21

of readings directly out of the out of

17:24

the laser and then we’ll take another

17:25

set directly out of the mirror

17:28

sorry my results are a little bit on the

17:30

crude side but before we started to

17:32

clean we had 55.5 what’s going into the

17:36

mirror and 50.6 coming out which was a loss

17:40

of 4.9 watts and efficiency of ninety

17:43

one-point-two percent for that mirror

17:44

Hmmm can I be crude and say crap that is

17:50

terrible but

17:54

you saw how much we took off not very

17:56

much

17:57

the mirror was very very shiny before we

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

18:00

started and now it’s still very very

18:02

shiny but look at the difference that

18:05

the Clean has made, we took two results

18:08

just to be sure

18:09

one of them was 98.5 percent efficiency

18:12

and the others 98.9 percent efficiency

18:15

so whatever we want to look at we’re now

18:18

within two percent which is our target

18:21

we want to be 98% plus ideally if we get

18:25

97 we should be happy

18:27

98 is approximately the best we can

18:31

expect from the mirror itself so it’s

18:33

doing a little bit better than the best

18:36

that it could do. but of course we haven’t got

18:39

an exact measurement system here it may

18:42

well be a little bit out but the point

18:45

is it’s in the right ballpark this is

18:47

not in the right ballpark and those are

18:49

and we’ve seen the only difference we’ve

18:51

had is we’ve cleaned the mirror. To be honest

18:54

i didn’t know what i was expecting to

18:56

find

18:57

I’m here demonstrating and talking about

19:00

Mirrors I don’t know what these mirrors

19:03

are like so this is the first time I’ve

19:05

seen it for myself and here’s how we go

19:08

about trying to rectify the problem to

19:10

start with so we’ve worked on mirror

19:12

number one and we’ve seen we’ve got

19:14

significant improvement now we ought to

19:17

take a look at mirror number two now I’m

19:19

just going to run the test in dry mode

19:22

at the moment I.e. without the doohickey

19:25

in the way and I want to see what the

19:27

current is that’s being drawn by the meter

19:30

and it is 22.2 milliamps so the current

19:40

drawn is as expected

19:44

but the power out is not quite what I’d have

19:47

expected so let’s see what we’ve got

19:51

coming into mirror number two. 10.9

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20:09

to be honest we’re less interested in

20:11

the actual power that’s going in here

20:14

we’re not testing the laser tube at the

20:15

moment what we’re really interested in

20:17

is trying to work out what the power

20:19

loss is on each mirror

20:20

ok let’s get our acetone out and do the

20:24

same thing again as you can see i’m

20:26

showing you this time just how much of a

20:28

scrub I’m giving it. I’m pretty serious

20:30

about it

20:31

this is not ….. hmm……..

20:36

just a little bit of coloration onthe

20:39

cotton wool bud but not a lot

20:50

as you can see, I’m being

20:55

pretty aggressive

21:00

Again we just remove any residue with a lens

21:04

tissue

21:20

we go through the same procedure check

21:24

the input and then the output

21:28

there we go mirror number two is now

21:30

playing ball

21:32

it was ah losing four and a half percent

21:35

before we started now it’s losing

21:37

one-and-a-half percent so that’s good

21:43

now to check out mirror number three

21:45

which is up here what we’ve got to do is

21:48

to take the….., take the lens off so we

21:54

dropped the lens away, and we’ll fix that up

21:57

somewhere where it’s not going to get

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damaged

22:06

it’s gonna go backwards and forwards

22:08

there, and round and round but it will happily

22:10

sit there i think without any problem

22:12

yeah and we’re starting off with 11.3

22:31

11.0

22:41

ok now cleaning this mirror is more

22:45

difficult because we’ve got slightly

22:48

limited access to it we’ve got to go in

22:50

through this tube at the front here so

22:53

it’s going to be a lot more difficult to

22:55

scrub this one as i said i’m being quite

22:57

aggressive with these mirrors I certainly

23:00

wouldn’t want to do this on a lens but i

23:04

just happen to know that these are molybdenum mirrors

23:05

and they will take, to be

23:08

honest, quite a lot of battering around so

23:11

let’s just use our lens tissue it’s

23:13

quite important that you do use the lens

23:15

tissue to finish with because the

23:17

alcohol or either of these chemicals

23:21

will leave a residue on the surface of

23:24

the mirror and any residue that’s there

23:26

could change the ah… could change the

23:29

surface appearance as far as the

23:31

infrared is concerned and you don’t want

23:35

anything which is going to change the

23:37

crystal structure that reflects the

23:39

light so we’re going to start off with

23:40

about 11.6

23:49

and now i have a problem because this

23:53

mirror has not performed the same as the

23:56

others

23:57

we had ninety-four before nearly ninety five

23:59

percent before we started and after have

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

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cleaned it would drop to ninety percent

24:03

so we’ve actually made it worse

24:06

how come? Well I don’t know at the moment

24:09

because bear in mind i’m learning just

24:11

like you are how this system works now I

24:14

know how to clean mirrors and I know how

24:16

to check mirrors so this is an

24:20

interesting problem so there’s another

24:21

issue here

24:22

that’s not necessarily a mirror issue

24:26

hmmm it’s an interesting question the thing is

24:30

when I’m doing my mirror test i’m using

24:32

sixty-seven percent power so i’m going

24:35

to set my power on the pulse button to

24:37

sixty-seven percent now I think what I’m

24:43

gonna do, I’m gonna dip that target in water

24:52

because I don’t want that target to catch

24:54

fire at sixty-seven percent but i do

24:57

want to see the burn marks so I’m going

24:59

to gently pulse it

25:13

I’m going to take the middle away

25:15

because I don’t want the Ash there because the

25:16

ash will, the ash will start to set fire to

25:20

it

25:26

now i know Imight be smoking the mirror but we

25:29

can clean the mirror

25:37

now this beam is supposed to be so I’m

25:40

told a three millimetre beam

25:43

how can a three millimetre beam produce

25:48

a nine millimetre hole and I’m guessing

25:51

that’s nine millimetres so let me just

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

26:00

have a look see what size it is

26:08

bear in mind if it’s scorched some sort

26:12

of energy has caused it to scorch and

26:15

that’s 8.3 that way and the burn doesn’t

26:22

go downwards and that direction there

26:24

is 10.5 my point is i think that probably

26:33

what’s happening here we could well be

26:36

clipping the edge of the mirror because

26:39

this beam looks as though it is low and

26:44

we haven’t got very much mirror space to

26:46

play with now that will become obvious

26:48

when I start telling you about beams

26:50

next time but my suspicion is that if i

26:55

could raise that beam very slightly i

26:58

would get more efficiency what I’m going

27:00

to do is just tip the beam up very

27:03

slightly

27:03

let’s just give it a quick pulse you can

27:06

see it low

27:11

now if anything it’s slightly high there

27:15

we go

27:15

spot on the centre and here we’ve got a

27:19

summary of the results and it’s best not

27:22

to look necessary at the efficiencies

27:26

although we did raise the efficiency of

27:28

mirror one from 91.2 to 98.9 and mirror two

27:34

we raised that from 95.7 to 98.5 and

27:39

mirror three

27:40

well that was 94.7 to start with and we

27:43

didn’t actually raise it at all

27:45

we made it worse until we realigned the

27:49

mirror and then we took it up to 97.1

27:51

which is still not perfect it’s not as

27:54

good as it should be but three percent

27:56

loss two-point-nine percent loss is

27:58

within the realms of acceptability I

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

28:01

would prefer it to be two percent or below

28:03

but this really sums up what the

28:12

situation is and why it’s important that

28:14

you keep your mirrors in good condition

28:16

if we started off with 60 watts

28:21

then if we left it as it was we would

28:24

have dropped to 54.7 at mirror one, 52.3

28:29

at mirror two and 49.6 at mirror three so we’ve

28:36

lost nearly eleven watts across three

28:39

mirrors, eleven watts out of 60 is a

28:43

big chunk. Now that we’ve fixed the

28:47

mirrors with a 60 watt output we would

28:50

have been 59.3 at mirror one, 58.4 at mirror two

28:54

and 56.8 at mirror three

29:00

so no we’ve only lost 3.2 watts, now 3.2

29:07

watts is very good because that’s about

29:09

five percent. Well you can see what it

29:12

says in my cup, I’m enjoying life and what

29:17

we’re doing here

29:19

they’re not really lessons because I’ve

29:23

got no idea where each one of these

29:25

sessions is going. I choose a subject we

29:27

decided he’s going to be mirrors today

29:30

and we looked at the mirrors on this

29:32

machine it’s the first time I’ve looked at

29:34

the mirrors on this machine and investigated

29:36

them so I’ve got really no idea what we

29:38

were going to find but that’s the way

29:42

that I like working and I enjoy it. Problems

29:49

bring them on, we’ve seen a few problems

29:52

today and I had a few problems in the

29:54

last week or so I was doing to Christmas

29:57

cards

29:58

oh and this is the run-up to Christmas

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

30:00

and these mince pies are really delicious

30:07

now because it’s not polite to speak

30:08

with your mouth full, I’ve cut out the bit where I

30:11

was enjoying a mince pie i have got another one

30:17

here but I’m gonna save that for a few

30:18

minutes time with these sessions I shall

30:21

never know where quite they’re going to

30:23

lead to today we’ve very conveniently

30:27

led into the next session about beam

30:31

alignment a few days ago as i said this

30:35

is the run-up to Christmas here. I was

30:37

using this machine to cut christmas

30:39

cards and i discovered a small problem

30:43

with this particular machine that wouldn’t

30:46

normally be spotted by most people the

30:50

beam itself the crossbeam there’s a

30:52

relative squares problem between the X and

30:55

the y axis it was only small but with my Christmas

30:58

cards when I did a fold into two there

31:00

was just the merest amount of

31:02

misalignment between the two edges which

31:05

told me that there was an out of squareness

31:06

problem now being the sort of person I

31:10

am

31:11

it was an excuse to rip the machine

31:13

apart i could have left it but i decided

31:17

not to

31:18

Um have I invalidated the warranty, who cares I

31:25

didn’t have a warranty on that one

31:26

basically i fixed the problem and it now

31:31

is perfect but in doing so I screwed up

31:35

the beam alignment, and that took me into a whole

31:40

new area my competence at beam alignment

31:44

is moderately good on the little Chinese

31:47

machine I’ve got over there

31:48

this machine is a completely different

31:51

arrangement, the way the mirrors are set up

31:53

the way the mirrors adjust and it caused

31:56

me quite a few issues so i felt that it

31:59

was a good time to look at beam alignment

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

32:02

as the next subject

32:04

following on from mirrors and today the very

32:09

last thing that we saw at mirror three, I had

32:11

to tweak the alignment to get the

32:14

efficiency out of that last mirror and

32:18

that just demonstrates how critical it is

32:20

that your beam is correctly aligned the

32:23

last session told you how important it

32:25

was to look after your lens and understand

32:27

what your lens does this session

32:30

hopefully has shown you how important it

32:32

is to look after your mirrors and

32:34

understand why they need to be cleaned

32:37

regularly and then the other question is

32:39

do you need to clean them regularly? What you

32:42

really need to do is be in a position to

32:44

monitor them with some sort of power

32:47

measuring equipment so i think most

32:50

people should have some sort of power

32:52

measuring equipment now this is

32:54

something I designed myself and it’s

32:57

it’s a DIY thing which is that bits of the

33:00

kits are available and if you need then

33:02

you can talk to Thinklaser about it

33:04

and they will they will explain the

33:06

situation to you

33:07

they have got their own meters that

33:10

they could probably sell you

33:12

the choice will be yours but you will

33:17

see me using this quite a lot in the

33:19

future and it’s one of the most useful

33:22

tools in my armory now because i’m doing

33:27

this work with this piece of equipment

33:30

I’ve glossed over it today but as a quick

33:34

aside i have noticed that the laser tube

33:37

itself is a bit inconsistent in his

33:39

performance so I’m gonna have a quick

33:42

word with Thinklaser about that

33:44

because it isn’t meeting my expectations

33:47

for an EFR tube but to be honest i’m

33:52

using this machine a lot i’m not using

33:54

that machine as much as I thought I

33:56

would

33:57

I’m rather in love with this machine

Transcript for How to Care for and Clean Laser Mirrors (Cont…)

34:01

it’s nice and simple to use, it’s quick, it’s clean,

34:03

it quiet

34:05

yeah definitely falling in love with it.

34:10

you know I shall keep finding excuses

34:12

to pull it to pieces

34:14

just because it’s me so don’t get upset

34:18

because you see me pulling them into pieces

34:22

I’m just a natural destroyer I like to

34:25

rebuild it make it better but pulling

34:28

it apart and looking at how it works

34:30

I don’t feel comfortable about a piece

34:32

of kit until I’ve done just that and

34:34

I understand every part of it works so

34:36

you’re probably come along with me

34:39

during that session and you’ll find out

34:41

more about your machine through these

34:43

sessions than you probably ever will

34:45

from your

34:46

engineer or from any tutorials that you

34:48

might look at on the old inter-Web so

34:53

anyway thank you very much for watching

34:54

as I said you might not be watching this

34:58

until the new year but it’s coming up to

35:01

Christmas so I’m going to wish you all a

35:04

very happy Christmas and a very pleasant new

35:06

year. Cheers