Making patterned mirrors and ITO glass with a thermal evaporator----make money online

hi everyone I made a lot of progress of

my thermal evaporator this weekend and

made some interesting mirrors these are

just patterned aluminum sort of a dot

pattern there and then I also made IT o

glass so these two are coated in IT o

and unfortunately they aren't conductive

so I have some more work to do there but

at least the evaporator is mostly built

and I can actually start experimenting

with using it as opposed to just putting

it together so as you can see the

aluminum coated glass is you know pretty

low resistance kind of about 10 to 15

ohms between those two points

but the IT o is completely open and this

meter will measure up to you know 30 or

40 mega ohm and it's not even

registering that so there's something

quite wrong with the ILO coating so let

me tell you about what I built and how

to use the evaporator when we last left

off with the vacuum chamber project I

had most of the valves connected and

vacuum gauges connected and I could

bring the chamber up and down from

atmosphere to vacuum pretty quickly

through all through the valve

arrangement so this weekend I added low

voltage feed through so that I can send

power into the chamber and also added

two rotary shaft feed through so that I

can move things in the chamber while

it's under vacuum the process of

physical vapour deposition or thermal

evaporation is fairly simple you

basically just heat up a material and it

vaporizes and then the vapor hits

something like a sheet of glass and

condenses back to solid form so if

you're going to make a mirror you put

your piece of glass above this

evaporation unit and it gets very hot

and you put aluminum into the evaporator

dish and the aluminum turns to vapor and

hits the glass and you end up with a

mirror the reason that this doesn't work

out in your shop environment the reason

the whole reason you need a vacuum

chambers that the aluminum molecules

would oxidize if they hit air and also

their path would be impeded so even if

they didn't oxidize upon hitting the air

there would be no way to get the

aluminum from your evaporator dish up to

the glass

without being bombarded by tons of air

molecules and that would basically stop

the process from happening a common way

to evaporate materials in this industry

is through the use of a metal boat and

it's really just a thin piece of metal

about five or ten thousandths of an inch

thick with a dimple punched in the

middle so you put your material to be

evaporated in the dimple and then pass a

lot of current through the boat and it

heats up till it's orange hot or even

yellow hot and the material will

evaporate off the boats are rated for a

certain current and voltage and you can

find this out from the datasheet so I

bought these boats from Curt jail esker

which supplies lots of different vacuums

stuff online and the boats were

relatively inexpensive compared to most

of the stuff that Wesker sells it might

have been about thirty dollars for five

of these boats and the boats come in

three different metals tungsten

molybdenum or tantalum to supply the

power to the boat I got a microwave oven

transformer and cut away all the

secondary windings so I was left with

just an empty core and a primary then I

rewound it with some very heavy of four

gauge welding wire so this is stranded

rubber insulated wire and I managed to

get about three turns into the

transformer in theory this should give

me the Transformers original power

rating of you know maybe you got a

kilowatt but the output voltage is only

two or three volts so the current is

quite high and we're going to need a

device to throttle this down or at least

provide some control over it so an

obvious choice is a very AK and this is

a very under sized very active and I

have to get a larger one because it

won't run very long without becoming

much too hot one side of the electrical

boat I connected directly to the

aluminum base plate just with an

aluminum standoff that I bought stopped

from McMaster the other side you need to

be passed through the base plate so

insulating but still holding the vacuum

in so I turned a piece from copper and

threaded both ends on it so one end you

had a 3/8 16 thread and the other end

had

quarter inch twenty thread and the idea

here is that the shape of this piece

would allow it to pass through the base

plate and be insulated via a piece of

shrink wrap and also seal the vacuum via

a sort of a homemade washer they're just

punched out of buna and rubber and on

the underside the thread would be

connected to the transformer through a

lug and on the topside the boat would be

connected to it through a nut and some

washers the rotary pass throughs serve

two purposes first one of the one of the

pass throughs is for a shutter which I

haven't installed yet so the idea is

that when you evaporate your material

what you want to do is get it up to

temperature so that it's evaporating

with a shutter closed so that it's not

actually impacting the surface that you

want to coat and then once the process

is underway and running smoothly you can

open the shutter and get a very clean

deposition otherwise when you first

bring the temperature up you might start

evaporating junk you know oils and dirt

on the surface that you would rather

have impact the shutter and not your

actual work the second pass through is

so I can actually move the substrate

while the evaporation process is going

on so one of the problems is that the

center of the glass or whatever it is

that we're coating will have a much

thicker coating than the outside because

of the physics of the way this process

works so one of the ways you can get

around this is to actually move the

substrate in fact you really want sort

of two movements you want an orbit

around the center and then you also want

sort of an orbit around the center of

the piece so that you end up with sort

of even coverage going on I don't know

if I'm going to do the full two axis

rotation but at least having one will

help quite a bit here's how I implement

to the rotary pass throughs this is sort

of a cross sectional view of the

aluminum base plate and I milled a bunch

of profiles into the top and bottom of

the plate and what I do here is press a

bearing in to the top cut out and into

the bottom cut out but in between the

two there is one of these this is a neat

little spring-loaded shaft seal that

mcmaster cells and it's pure Teflon and

a stainless steel spring in the middle

to give it

some resiliency so I was kind of

skeptical how these would work but

actually their performance is quite good

down to the base pressure of my chamber

which is you know 1e negative 5 or even

lower and so the idea is that you just

machine a 3/8 inch diameter counter

board hole into your into your metal and

then push this in so that the spring is

on the atmospheric pressure side and

then put the shaft through that and you

end up with a really nice high vacuum

seal and since it's all Teflon you can

clean this with aggressive solvents and

it won't out gas very much and all that

I chose open bearings that aren't

shielded or sealed so that the space in

between the two bearings has a chance to

vent so when putting together vacuum

systems it's important to make sure that

you don't have any spaces in the chamber

that are too well sealed off or kind of

almost sealed off so also when screwing

things down like that aluminum standoff

I cut a slot in the side of it the idea

being that you might end up with gas

trapped in the space but behind the

threads basically so that channel allows

all the trapped gas volume to escape out

of there when you're pumping the chamber

down another thing to keep in mind is

that the shaft is going to try to get

pulled into the chamber so you've got

atmospheric pressure basically trying to

push the shaft into the chamber and so

you're going to want to put some collars

on there to keep that from happening so

the full stack up looked like this

I had the shaft with a clamp on collar a

spacer and then going through the whole

bearing set up which is pressed into the

base plate and then another spacer in

collar on the outside so this way the

shaft is completely constrained and if

you try to push on it side to side the

shaft seal won't experience very much

force because you've got two bearings

pretty far apart holding this in place

if you build this yourself definitely

use a clamp on shaft collar like this

instead of a set screw style collar like

this that has a

hex set screw there and the reason for

that is that these set screw collars

will leave a mark on the shaft kind of

like that and it may not seem too major

but the set screws that they put in

these are actually purposefully cut

pointed so that when you screw them down

they dig into the shaft and the problem

with that is that this this small amount

of denting or gouging in the shaft is

enough such that if you try to put your

machine shaft through here you'll

actually get hung up on the on the

dimpling caused by the caused by the set

screw and also you wouldn't want to put

this shaft with the with the cut up sort

of surface here through your very

expensive teflon seal so always use the

clamp on collars also the two-piece

collars are good because you can slip it

over the shaft without having access to

either end the shafting is 12 L 14

leaded steel this is kind of my favorite

steel alloy because it's so machinable

it's also pretty hard and McMaster sells

it for you know relatively cheap without

ground finish which is nice so I also

got a hold of some i teo pellets or it's

really looks sort of like gravel also

from curt let's go and check that the

conductivity is actually quite good so a

little pellet of the thing is as low as

my meter can read it's under an ohm and

i put a pellet into a tungsten boat and

evaporated it but finding information

about how to actually do this like the

temperature the rate that the thing is

going to vaporators all that stuff is

fairly difficult so i've done my best

here with guessing and my initial guess

looks like it's not going to work I

think one of the factors that may be

hurting the performance here is the

substrate temperature so it seems like

in the literature in the small amounts

that I've been able to find the

temperature of the glass that's

receiving the I tio must be pretty hot

like a couple hundred degrees C so I

might have to add like another heater to

the chamber to get the substrate

temperature up so that will involve

another few pass throughs and

thermocouple and a temperature

controller and it looks like the

projects a little bit more complex than

it even I originally thought

so eventually my plans are to make an

LCD or an OLED or TFT or any of those

things that we can do with thin film

deposition and probably photo

lithography okay see you next time byeTop Paid Keyword :  earn cash online, google make money from home, earn money online without investment by clicking ads, free earn money website, online money making jobs, earn money online without investment by typing, online work for money, best online earning sites, make money online with google, online earning websites, money making websites, online earning websites for students, invest online and earn money, best online money making, online money income, view ads and earn money without investment, earn money online by clicking, online money income site, money earning sites, online earning sites, best website to earn money,