Re: Magnetizer
Sulaiman, Sat Sept 12 2015, 09:44AM

The best person to ask is Russ,
and he can be contacted here

Re: Magnetizer
DerAlbi, Sat Sept 12 2015, 09:03PM

It should be straight forward.
You need a charger, a capacitor and an SCR and money.
WIt what exactly do you need help?

Re: Magnetizer
rajheman, Mon Sept 14 2015, 09:26AM


I want to make magnetizer as mentioned in russ video model MZM3040
MZM 3040
Has input power of 230VAC
Out put power is
3000dc voltage with 30kA current with 4000 microfarad capacitance
With 18000 joules out put energy

This is my idea to do homemade magnetizer

In this below image
there are 2 micro oven transformer primary winding are connected in anti parallel and secondary winding are center tapped to get 4000volts with 75m amps .which is rectified with two 6kdiodes then charge the capacitor bank .the discharge from capacitor flow through fixture (copper winded ring where objects are placed to be magnetized ).





In above image I made question mark (?) at capacitor because I didn't have idea about how much capacitance is need to get a 30kA current.

I will make mini multiple capacitor bank in parallel to achieve high capacitance.
My question is how much capacitance is need for a capacitor to get 18,000j energy output (30k amps) by supplying 4kv DC with 75mamps current ???

Re: Magnetizer
dexter, Mon Sept 14 2015, 09:47AM

depending on how fast you want to charge the cap, full wave rectifier might be required

charging resistor is absolutely necessarily or else the diodes wouldn't survive

a switch is required between cap and coil - you need to first charge the cap then discharge it through the coil

as a switch you can use: heavy duty spring loaded mechanical switch, triggered spark gap or big SCR

Re: Magnetizer
DerAlbi, Mon Sept 14 2015, 03:27PM

I didn't have idea about how much capacitance is need to get a 30kA current.

A few pico farads.

Re: Magnetizer
Sulaiman, Mon Sept 14 2015, 06:39PM

rajheman, in his video clips Russ may look a little 'rough'
giving the false impression that this kind of equipment is just a little bit dangerous
Russ is very experienced, and this kit is a one strike you are out deal.

please take this constructively;
you had to ask such a basic question
and your circuit diagram shows no sign that safety is uppermost in your mind
so even though it is doable, please do not.
Start with any voltage but current limited to a few mA
not spectacular but fun and you learn a lot (quickly .. ;)

can't loose 4HV members !

Re: Magnetizer
2Spoons, Mon Sept 14 2015, 09:54PM

Ok, lets just take a step back for a moment, and ask one very important question - what do you want to magnetise? Because the whole system starts there. From there you can calculate the field intensity needed to achieve the desired remanent field, and from that you can work out how much energy is required to create that field. Note that energy is the determining factor, not peak current. Peak current drops out of the combination of energy and number of turns on your magnetising head - so you have some control there in your design.

Be sure that you build your mag head really solidly - they have a tendency to unwind when hit with such a massive pulse!

Re: Magnetizer
Sulaiman, Tue Sept 15 2015, 01:14PM

2Spoons, I've only made or used steel magnetizers where roughly, power usage and copper weight seem the main consideration,
You mentioning that it is the energy lit a little lightbulb for me in another area, thanks.
Out of curiosity, do you happen to know what are easily achievable amateur peak flux densities .(some volume, say 10cc)(no LN2 or special machinery) ?
In these high peak flux air core magnetizers,
in practice, does energy absorbed (MG.Oe) by magnetization form a significant proportion of the energy input?

Re: Magnetizer
2Spoons, Tue Sept 15 2015, 10:32PM

My experience comes from 20 years ago, working for a whiteware manufacturer where we made our own motors. We were achieving something like 4T in the magnetiser head, in order to magnetise a bunch of ferrite segments in an injection moulded rotor. The mag head was a big chunk of laminated iron (roughly 40cm x 40cm x 10cm), with about 6 turns on each pole, from memory. Nothing fancy about the system - just a big fat cap bank, with big fat thyristors and big fat copper cables.

So on that basis at least 4T should be achievable by the enthusiastic amateur.

Re: Magnetizer
rajheman, Wed Sept 16 2015, 02:27AM

Thanks for the response guys :).
Ya I know safety is first . the image which I mentioned here is just for the working principal of magnetizer.
Dear sir 2spoons I want to make this magnetizer to make a neodymium magnet of 8inch dia * 3 inches height disk .
My question is does my input power of 4kv 75m amps from 2 MOTs is sufficient to charge capacitor bang to get 18000 j energy ??

Re: Magnetizer
dexter, Wed Sept 16 2015, 05:46AM


what do you mean by sufficient?
a better question is in how much time do you want the cap bank to be charged?
and from that a charging current can be calculated

Re: Magnetizer
2Spoons, Wed Sept 16 2015, 06:57AM

Ok, you got me hooked (damn you!). I had a quick play with femm - if you surround your "magnet" with a steel mag head ( ie no air gaps) and put the coil around the periphery of the "magnet" I get a figure of roughly 200000 A.T to generate the 30kOe field needed. Thats about 15000J in the coil. The coil was modelled as single turn of solid copper 0.5 inches thick and 3 inches high, with an ID of 9 inches. It ends up dissipating 500kW. The real coil will need multiple turns to drop the current to something feasible, and slow the pulse down to allow field penetration of such a large piece of neo.

So... scary, but doable, though I have no idea how you plan on separating your finished magnet from your magnetising head.

Re: Magnetizer
rajheman, Mon Nov 30 2015, 05:32PM

hi guys after a long time ...i got free time to work on this magnetizer, toady i got two mots from local electronic shop cost 19$ each ..
on googling i got same piratical project on 24k joule capacitor bank discharge using open-air thyratron system by cevyn

his work is well matching to my work to make my magnetizer .
but i have one doubt in charging system.how to monitor the power while charging the capacitor bank . because the out put from two mots is above 4KV ..my multi meter reads only upto 600 volts .
i want to monitor power while charging the capacitor bank ..any ideas please help

Re: Magnetizer
klugesmith, Mon Nov 30 2015, 08:29PM

It's alarming that you are working with lethal electricity before you understand how voltmeter scales are determined.

STFI and read about how voltmeters work. Learn how you can make one for any desired full-scale reading, or adapt yours to read higher voltages. For a topic so basic and universal, "search the Internet" does not mean "ask on a forum". Unless you want to demonstrate laziness on top of ignorance.

Please come back after you have measured the AC output voltage of a MOT and lived to tell about it.

Re: Magnetizer
DerAlbi, Mon Nov 30 2015, 10:45PM

hmmmh.
klugesmith.. i was more concerned about the fact that he wants to measure "power" while charging the capacitor bank with a "volt"-meter...
but your rant also delivers the right message
thx for doing the job, i didnt want to be the negative guy again.. i guess i fear to become known for that. hmmmmmmh

Re: Magnetizer
Signification, Tue Dec 01 2015, 03:37AM

...gives me a scary feeling...
MOT's in series rectified and filtered...use NST('s)!! especially for only 75mA.

OK;
I would use the FWB,
AND be sure not to use 1/4 Watt resistors--they can go like a "bomb" due to insufficient voltage rating.