Transparant Heating Elements !

[insane_alien]

well, peanut oil could probably be made clear somehow(i'll have to look it up though). but people are probably going to want different coloured fluids and glasses anyway if this ever hits the market 'just cos it looks purty'

[Rocket Man]

i have another idea, why not simply have it sitting on a pedastal with an intense infra red source pointing at it. (co2 laser anyone?) of course you wouldnt see the light, but you'd see the bread going brown, a normal toaster uses mainly IR transfer of heat anyway, it does use convection to a limited extent but you'd get much the same effect by simply shining IR at the bread.

[swansont]

use peanut (groundnut) oil, it easily takes those sorts of temps and higher before it tries to vaporise, and as it would be a sealed unit there`s worry of oxidation over time, and IF there was ever a leak, it`s perfectly edible too

 

I think that's a WHEN rather than an IF.

 

Another problem with a liquid system is that you are going to lose heat in both directions and you need glass thick enough to safely contain the liquid. The advantage of the heating element on the inside of the glass is that you are using the insulating properties to your advantage, since you really don't want something that gets hot on the outside. A liquid system is gong to require much thicker glass on the outside, and thinner towards the bread.

 

The fact that somebody is trying to commercialize this and has thus far failed indictaes to me there is an uphill battle ahead for this as a garage project.

[insane_alien]

way to burst the bubble swansont. are we not allowed to dream?

[gcol]

Have you considered brake fluid? boils from 150 upwards depending on grade, designated in Dot units, up to about 200c. Lower if contaminated with water. Dont know about colour.

[insane_alien]

seems good but it is toxic so if it burst it wouldn't be very good.

[John Cuthber]

Does anyone know what the upper temperature limit for ITO on glass is?

[YT2095]

glass is used as an example here you could use fused Quartz like that in Halogen lamps, but simple Borosilcate ranges from 700 - 1200c, plenty sufficient when your only looking at 250c Max.

 

and Convection is Perfectly adequate in this instance also (think electric Oil Filled radiators).

 

Swansont Why do you say When? if the seal is adequate it shouldn`t leak ever. think Glorified Lava-Lamp here

[insane_alien]

well, if it ever got mass produced some would leak. i've seen leaky lava lamps.

[qwerty123]

well im not really thinking of mass producing it but hey if i get itworkign then why not lol ! I dont think i would be able to use the thin metal anyway becuase of patent protection on it. So the liquid one seems good to me and seems possible. But would the toast need to be virtually touching the glass ? On the users side of the glass it could be heat proof ?

[insane_alien]

no one said the liquid had to be dead centre or that its made of a single type of glass. or that it even had to be glass in the first place.

[qwerty123]

ye true ok

 

thnks

[John Cuthber]

I know how hot you can run glass. I wondered about the ITO.

[insane_alien]

what is an ITO? i looked it up on several websites but i can't seem to find anything that fits the context.

[qwerty123]

i been looking aswel cant seem to find anything ?

[insane_alien]

closest thing i've found is the italian trade organization

[Rocket Man]

my comment on post 52, what sources of infra red light would be capable of this sort of thing? you could have a reflector underneath the bread and the bread in a simple wire stand. if you felt like being really safe you could get a material for a veiwing window that blocks IR but not visible. (it really only needs to be as safe as a toaster, curtains are still allowed to catch fire)

[insane_alien]

Rocketman: yes it could be done but lasers get hot and don't have the highest of efficiency i thought of it earlier but i done some research and filed it under possible but impractical(although this entire thread should be filed under the same heading)

[Rocket Man]

hence the (poorly worded) question of alternative IR sources

i think you could do this with a heating element much the same as in a standard toaster but with a reflector/focussing optics

im thinking a linear element at the focal point of a roughly parabolic mirror.

[YT2095]

John, ITO treated glass won`t take the temps high enough to make toast, it has the same problem as the wires, IIRC about 150c tops

[qwerty123]

is there anything that can take that heat and be transparent at the same time ?

 

Thanks

[YT2095]

I think that`s been answered here quite extensively!

[qwerty123]

oh sorry i was talking about the glass , or plastic that could take the heat:P

 

Thanks

[gcol]

I saw an episode of "mythbusters" recently where a sheet of glass between a bodyheat source and an infra red detector rendered the detector ineffective.

Are you sure that glass will transmit the energy spectrum you want? My oven door is glass, it remains relatively cool whatever the oven temperature.

[qwerty123]

maybe a cermanic isnt the best thing to use then ? Im thinking maybe seomthing else ?