Hi Folks! This is a fairly simple to make laser,
called the TEA laser. It's made of simple parts like aluminum foil,
nuts and bolts, and so on, that you either already have or can find in
local stores. I'll show you how to make it and adjust it
so that it works. This design comes from Nyle Steiner of sparkbangbuzz.com,
and he calls it the Against the Wall design.
Here are the major pieces that are needed.
This is my homemade high voltage power supply. This ball is connected to Earth ground
and this ball is high voltage positive. There's a spark gap here.
There's also a very long spark gap here. That's where the lasing happens,
the creation of the laser beam.
On either side of that spark gap are this angle piece
and this angle piece.
And lastly, there are two capacitors here. One is formed by this small sheet of aluminum
foil, the dielectric which in this case
is a sheet of polyethylene, and the larger sheet of aluminum foil under
that. The second capacitor is this small sheet of
aluminum foil, the same sheet of polyethylene,
and the same larger sheet of foil underneath.
And now to make it.
The dimensions I'll give aren't very important, but I'll show what I used anyway.
I start with a piece of particle board for the base,
followed by a sheet of aluminum foil. This will be the bottom plate for the capacitors.
I leave some hanging over this end for making electrical contact with later.
Next comes the dielectric for putting between the foils,
for the two capacitors. I've gotten it working with this polyethelene
which I got at a carpet store. It's normally used as a vapor barrier under
carpets and in walls in North America.
I've also gotten it working with this clear sheet material
which I got from a photocopying store, in my case the UPS Store.
It's normally called transparency film and is used for making transparencies for
giving presentations. You can buy them in packs of 50 or 100,
but a place that does photocopying will often sell you just a few sheets for
a lot cheaper. They're both 0.0045" thick.
You want something very thin, but that can handle high voltage.
It's important to have it extend passed the aluminum sheet here,
and here, by at least a half inch or a cenitmeter, to prevent arcing around the dielectric.
However, the aluminum should not be covered on these sides here
and here.
Next comes the two small aluminum sheets, for the top plates of the capacitors.
I first cut them out, and then put them in place.
An important thing here is that there is plenty of dielectric
between their edges and the exposed big sheet below,
again to prevent arcing. I space them out 1/8".
The two edges here at the gap are these two edges here when I cut it out.
Those are going to be straighter than the edges where I was doing the cutting.
Notice that I didn't tape them down. Instead, when I apply the high voltage,
the charge will attract everything flat together.
Next comes the two angle pieces. They come from a longer piece which I bought
at Home Depot, though many hardware stores have it.
It's 1/16" thick. Make sure it's not anodized,
like this shiny piece. You can check it by measuring the resistance
with a meter. It should have very low resistance.
Anodized aluminum will have infinite resistance.
I cut mine so that they're a little longer than the small aluminum sheets are wide.
I then file the edges so they have rounded corners
and are clean. I don't do anything to this edge
since that's already good from the factory.
Notice that this angle piece sits up off the foil.
That's due to this thick wire underneath. The wire is held in place by being bent around
two notches in the angle piece.
To do that I first cut a piece of wire, in this case 18 AWG bare wire,
so that it's longer than the angle pieces. I then make marks for the notches around 1/16"
inch in, and use a hack saw to cut the notches,
one on either end, such that the wire fits in the notch.
The wire has to be straight. It's important that it contacts the foil
and the angle piece along it's entire length underneath.
So I put it in my vice, along with the angle pieces since the vice
isn't long enough, and press the wire straight,
rotating it into different positions as I go along.
Then I put the wire in place, and make sure the ends are flat,
using the vice again.
I'm going to be adjusting the gap where the lasing is taking place in real time.
So I need a safe way of doing that without getting shocked.
These straws are long and non-conducting so I hot glue them to the back of one of the
angle pieces.
I'll move things around later when I adjust things,
but next I put down the two angle pieces. To hold them firmly down I have some baggies
filled with sand. This is very important for this angle piece
because it presses the thick wire underneath flat,
ensuring good contact along the whole length.
Next, I need to make this spark gap using two short angle pieces.
To do that I need to make a threaded hole in one of them.
This screw is 1/4" with 20 threads to the inch.
So I use this drill and tap set to make the threaded hole.
I start by using the 13/64" drill to make the hole.
And then I put the tap in a "T" wrench and use it to make the threads in the hole.
A quick test shows it's good. Using some nuts and a bolt, I assemble it
all. The tip of this end of the spark gap is this
round cap nut.
I put the first spark gap piece here at the edge of this small aluminum sheet.
And then the other spark gap piece here on the big aluminum sheet.
The two angle pieces need to be electrically connected together
across the top with a resistor. Anything between 1 kilohm and 1 megaohm will
do. I'm using 100 kilohms.
An inductor will also work.
I'm using my homemade high voltage DC power supply.
It's capable of 30 kilovolts and plenty of current
but I'll have it turned to very low, certainly less than 10 kilovolts.
It does have to be a powerful one though.
I put the high voltage positive output on this small aluminum sheet.
This wire goes to Earth ground, which is the negative for my power supply.
I connect it to the large aluminum sheet by sitting this metal ball on the end I left
overhanging.
Now to adjust it.
As I said, the distance between these foils should be 1/8".
I put the angle piece with the thick wire on top of this foil.
I want the thick wire to be in electrical contact with the foil,
with the edge of the foil not visible in the gap.
Then I put the wall piece in place, with a gap of just over a millimeter.
I put the weights in place. And don't forget to put the resistor
across the top of the two angle pieces.
I put some white paper in place to act as targets.
I start with the spark gap fairly close so that I don't destroy my capacitors right
away with too high a voltage.
I wear welder's goggle to protect my eyes from the strong ultraviolet radiation of the
spark, and from the laser.
I turn on the power supply. And the spark gap should start sparking.
I use the handles to adjust the long gap between the angle pieces
where the lasing will happen. When it works,
bluish spots will appear here and here on the white paper.
When the spark happens here, this small capacitor will discharge,
starting from this end first and then all the way to this end.
One approach is to adjust the gap so you see sparking at this end
and then slowly decrease the size of the gap toward this end
until you get sparking there too, or the lasing starts
and you see spots on the paper whenever there's sparking.
But you can also try with sparking starting at this end end first.
If it still doesn't work, turn off the power supply and safely discharge
everything. I use a grounded wire taped to a long stick.
One possible reason it didn't work is the spark may not be strong enough.
Increase the size of the spark gap so that there's more charge built up before
sparking.
Turn on the power supply and try again.
Of course if you made the spark gap too wide then the voltage will become too high
and you'll break your capacitor, like I did here.
The voltage was high enough to blow holes through the polyethylene dielectric
and both layers of the aluminum foil.
I blew mine 9 times in the making of this video,
having to cut new foil and polyethylene dielectric each time.
Eventually, though, you'll have success.
And here it is in action. Notice that you can't see the laser beam.
It's ultraviolet light, which our eyes can't see.
But when it hits white paper, the paper gives off visible light,
it fluoresces. You can also draw on the paper with a highlighter
pen and the ink also fluoresces.
Or you can put highlighter ink in tap water and it fluoresces as the beam passes through
it.
And here I'm trying out the transparency film that I mentioned,
instead of the polyethylene as the dielectric. Since it's transparent,
you can't actually see it, which is why I use the green polyethylene
for most of this video.
Well, thanks for watching!
See my youtube channel, rimstarorg for more videos like this.
That includes one with more TEA laser demonstrations including testing with a mirror.
One on how the TEA laser works. And one on how to make the high voltage power
supply I used.
And don't forget to subscribe if you like these videos,
or give a thumbs up or leave a question or comment below.
See you soon!