Electric Chair

An electric chair AND LEDs, oh my. However, this instructable  is more about a demonstration on the coefficient of thermal expansion between different materials. Before I lose your attention, did I say that there was going to be molten glass, LEDs, AND an electric chair ( in this case, a small chair like object with current running through it).
 

I am encasing a very, very simple circuit in molten glass that brings up a few interesting things:

1. Glass is a conductor when molten, something you do not hear about too often in your electronics books, but then again, how often does this situation come into play.

2. Glass is an insulator when not molten, though  technicality speaking glass is never completly solid. The molecules are still ever so slightly moving, meaning that your kitchen glass will eventually slump. However, this slumping may take a couple thousand years to do that.

3. Copper can be combined with molten glass. This ia a loose statement with way too many parameters for why this can and cannot work.

If you are inclined to get your geek-on, I will put a bit more info on another page in this instructable about the science behind combining these materials in this situation.

 

Step 1 Making a simple circuit with copper wire

 

I used copper wire that was twisted and crimped to make part of the simple circuit. Since this will be encased in 2000 degree molten glass, I am pretty positive that solder won't hold up too well.

I am just guessing, but things like IC chips and mosfets won't hold up to 2000 degrees either.

I did not want the copper too thick because there is a good chance the glass will crack. This will be explained later.

Comments

[anneangersbach]

Really old church windows show how hard glass is still fluid. You might have to come to Europe to see some old enough. They are way thicker at the bottom than at the top now.

Love the result of this instructable. Too bad i cant melt glass in my kitchen ;) do you think this might work with other clear materials? Maybe there's some acrylic stuff thats suited for home use?

[Orkekum]

The reason glass is thicker to bottom, is all for stability, it's stronger than way

[belliedroot]

Well, zag1024 was right with his comment based on recent research. The belief now about church windows being thicker has more to do with how they were made. However, even the Corning Museum of Glass had an exhibit showing glass that had slumped over time. But hey, Pluto was still a planet a few years ago and now its not.

As far as doing something with cast acrylic, YES. In fact, I wish I had thought of that as an alternative if someone does not have access to a glass studio. You have many more options since you won't be dealing with extreme heat.

I was just trying to demonstrate the possibility of combining a working circuit with hot glass. Using LEDs then takes advantage of light and glass.

[anneangersbach]

I have never done anything like this, but I really like how it works and especially how it looks. Much prefer the "artsy" one further in the instructable.
Could you link me to a shop with the kind of acrylic (or other) stuff that I could use at home? Not quite sure what to google for, especially not in English ;)

thx!

[belliedroot]

If you google ' casting resin ', or ' clear polyester casting resin ', tons of info will come up. I should point that resins can be dangerous to use like acrylic. The polyester resin that you can find at your local craft supply store like A.C. Moore is probably your best bet to start with. It is called ' Castin' Craft Clear Polyester Casting Resin '. You will need lots and lots of ventilation when you use any resin.

[tzq33tdq]

does this thing make its own power?

[belliedroot]

technically, no. That would involve nuclear fusion, and I am saving that for another instructable when I get it worked out.

In the video, you can see me pressing a switch. That switch is connected to batteries inside the box.

[tzq33tdq]

oh thank you very much.

[zag1024]

I don't work with glass, as you do, so I may very well be wrong, but according to wikipedia, it is unlikely humans will be around to see our kitchen windows "slump" - the amount of time predicted by one journal suggests that it would be longer than the age of the universe! Apparently, the increase in thickness at the bottom of old windows is caused by a manufacturing technique rather than the glass flowing over time. See http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass.

[belliedroot]

After reading your comment, I did a little research. I was off by a few dozen zeros on the time line, but it can still happen. Back in the day when I learned about it, that was the consensus. I haven't stayed on top of the latest research, so my bad.