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StormInABottle

Sun Jan 20 2013, 11:03AM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

So i have many cores. none of them is large enough for my evil plans. So i thought. Why not melt them and make a large core :D.
I can include pictures of all the cores i have

The transformer i am planning of is a flyback transformer with 3000 turns at the secondary coil and 4+4 turns as the primary.

The cores i have are from cfl transformers. and inductors
i have many

The largest transformer you can ever see on a computer psu.

A few ferrite pieces from radios

And a crappy dozen of broken pieces

2 U cores from a small flyback
2 U CORES FROM a large flyback that costs alot lol.

Also i plan to have the insulation between the windings purely red electrical tape.

A crappy dozen of it
How thick should the insulation be?

Also for the final insulation. After all the windings are done. I plan to put that in wax.. Or should i use oil. i prefer wax though. Cause it becomes solid lol..

Also should i put paper between the insulation layers.
So that it absorbs oil and wax and such?

Also what is the melting point of ferrite. I suppose i can't just microwave it

Can i melt it with some large fire.

What is it's melting point?

Also if you please give me the dimensions of that core i will make

Ash Small

Sun Jan 20 2013, 12:03PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Arcingnoob wrote ...

So i have many cores. none of them is large enough for my evil plans. So i thought. Why not melt them and make a large core :D.

Ferrite cores are made of powdered iron, or similar powder. You can't just 'melt them down'.

Just buy the biggest cores you can find.

I think TSC cores are the most reccommended ones on here, but I bought some 'big' EPCOS cores.

You can cut them, and epoxy them together if you are determined to use the ferrite you have, but by the time you've bought some tools you may as well just buy some decent cores.

They aren't that expensive.

StormInABottle

Sun Jan 20 2013, 12:17PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

it is that hard to find one.. when you have no credit card -_-

StormInABottle

Sun Jan 20 2013, 12:51PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

What about iron?

Can i make a 3000 turns flyback with IRON?

Ash Small

Sun Jan 20 2013, 01:45PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Not a high frequency one. You must know someone who has a card?

Sulaiman

Sun Jan 20 2013, 02:03PM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141

I have powdered/pulverised old ferrite parts
and made new parts by filling pvc tubes with the powder,
compacting it and adding polyurethane varnish.
(not a good choice - the center of parts takes months/years to set !)
Not much use for low-leakage transformers but
works ok for a flyback but needs about 2x to 4x the cross-sectional area
for similar performance to solid ferrite..
I've tried applying a large dc magnetic field whilst the varnish/polymer sets
but it seems to make little difference.
It's a nice experiment but I doubt I'll go to such effort again.

See if you can find some old flyback transformers (crt tv/monitor etc.)
and use as-is or remove the core to wind your own.

StormInABottle

Sun Jan 20 2013, 04:35PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

2 Things. No i know no one who has a card.. Only my mum and she will never lend me that. cause she hates buying online.. also the ferrite breaks easily. And gives no powdered crap. I am sure i can melt it. in the next day i get access to iron melting equipment.. i will try my luck

Dr. Dark Current

Sun Jan 20 2013, 05:28PM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

Maybe a two part epoxy varnish would work, but I think it's still way too thick. A core made in a such way must have a really poor permeability.

ZakWolf

Sun Jan 20 2013, 07:29PM

Registered Member #3114 Joined: Sat Aug 14 2010, 08:33AM
Location:
Posts: 608

Arcingnoob i wish you luck and check this out

this is my ~3000 turn flyback, hope it inspires you :)

StormInABottle

Sun Jan 20 2013, 09:09PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

Dude wolf. Your video is what inspired me in the first freaking place. I was trying to get results like yours D:

But i 'd make a more powerful secondary.. So just call it.. A improved version.. Also with a bulky transformer as the ZVS input..

Also i see no point why i can't melt ferrite cores from flybacks. cfl toroids and cfl transformers and a pc psu largest transformers
google says i can
physics says i can
Chemistry says i can.

Its some solid iron with certain impurities in my opinion.. And in all matters. I can always give it enough heat to break the intermolecular force to turn it into a liquid then shape it then cool it to return that force. And what i get is supposed to be the same material with it's original properties

Also wolf what did you use as insulation.. I see some kind of tape..

But i was thinking about electrical tape + paper
Then put it in oil to soak the paper in it
Then put the oily secondary in wax.. So i just get a core with 2 wires coming out lol.. the wax 'd seal the oil inside so the core would stay oily inside

Also at you Did you wind Left right.insulate right left insulate left right right left
Or right left insulate take wire to start point then right to left etc..

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