Something for the engineers .

[PeterSibley]

http://www.wimp.com/levitationmelting/

[MiddleAgesMan]

Slow start but a flashy-splashy finish!

[ChrisBen]

Gonna take you a long time to cast your keel that way.

[McMike]

WTH!!!! Splain!!!

[PeterSibley]

WTH!!!! Splain!!!

Achully... I was hoping someone else would .

[StevenBauer]

Someone's got a lot of 'splainin' to do.




Steven

[McMike]

Gonna take you a long time to cast your keel that way.

Lead was my first thought . . . but the rest . . . .?

[LeeG]

are those magnets ruined by the melting?

[McMike]

http://www.mindchallenger.com/inductionheater/

[McMike]

I want to make one.

[John Smith]

When I was a boy my dad and his friend made a little thing with magnet mounted on a pin, and coil of wire the magnet stood in the center of, and a condensor. Give the magnet a little push and it would spin at a pretty good rate of speed. It would continue to spin until, as I recall, the condensor went bad. It wouldn't do anything but spin. They tried a variety of condensors over time, but couldn't get past a month of spinning. I remember them wondering about putting it in a vacuum, but they couldn't figure out how to do that and give the magnet a push.

[McMike]

Induction . . . is it the same as the new fangled stoves they got out now?

[Keith Wilson]

Jeez, how much current is flowing through that thing?? I suppose it's made of a copper tube so they can pump cooling water through the coil. I like how the melted drop takes the shape of the coil. Very cool.

[ChrisBen]

WTH!!!! Splain!!!

If I gotta splain it.....

[PeterSibley]

I know industry uses induction furnaces but I don't know about the magnet!

[McMike]

Jeez, how much current is flowing through that thing?? I suppose it's made of a copper tube so they can pump cooling water through the coil. I like how the melted drop takes the shape of the coil. Very cool.

10kw 100A!!!!!!!!

[MiddleAgesMan]

Not lead, gotta be a ferrous metal IMO, most likely ordinary steel.

[LeeG]

Wow, it doesn't need to be a magnet

[Paul Pless]

Not lead, gotta be a ferrous metal IMO, most likely ordinary steel.

the second video shows a bit of copper levitating then melting

[StevenBauer]

So none of you can explain exactly what's going on here?




Steven

[Peerie Maa]

So none of you can explain exactly what's going on here?




Steven

Eddy currents both create repulsive magnetic fields and heat the metal. Wiki nails it:

Oscillating electromagnetic fields

A conductor can be levitated above an electromagnet (or vice versa) with an alternating current flowing through it. This causes any regular conductor to behave like a diamagnet, due to the eddy currents generated in the conductor.^[6][7] Since the eddy currents create their own fields which oppose the magnetic field, the conductive object is repelled from the electromagnet, and most of the field lines of the magnetic field will no longer penetrate the conductive object.
This effect requires non-ferromagnetic but highly conductive materials like aluminium or copper, as the ferromagnetic ones are also strongly attracted to the electromagnet (although at high frequencies the field can still be expelled) and tend to have a higher resistivity giving lower eddy currents. Again, litz wire gives the best results.
The effect can be used for stunts such as levitating a telephone book by concealing an aluminium plate within it.
At high frequencies (a few tens of kilohertz or so) and kilowatt powers small quantities of metals can be levitated and melted using levitation melting without the risk of the metal being contaminated by the crucible.^[8]

[ChrisBen]

So none of you can explain exactly what's going on here?




Steven

Induction Heater