Why ceramic magnets?

[Rhett]

i'm gathering the supplies to build my first bedini motor.

one of the things the peswiki calls for is ceramic magnets. it says they MUST be ceramic, but i can't find any indication of why through google searches.

here's a link http://peswiki.com/index.php/Directory:Bedini_SG:Materials#Materials_List

i already have tons of neo magnets lying around and, if possible, would prefer to use those.

can someone explain (or give me a link) why ceramic magnets must be used?



also on a side note:

i've noticed that the 2 sizes of mag wire used for the parallel wound coil are about 3 gauges apart in size with the trigger wire being the smaller size in all the plans i've come across so far.

would it be detrimental to the project if both wires were the same gauge, say #22 (i got quite a bit of that laying around also )

Thanks for any help or insight you can give me on these matters.

i really appreciate it

Rhett

[Ren]

Hi Rhett,

The wire should be ok. The sg calls for 23awg and 26 awg, the window calls for 23awg and 30awg. I think you'll find it will work fine, just use the thinner wire for the trigger.

It has been explained many times why neos arent ideal but perhaps not on these forums. You can still use them, your coil will need to be mounted further away. In the simple sg machine the magnets are a source of induction which the coil captures and uses to trigger the transistor to fire the power winding. If these magnets are overly strong, they will saturate the core and cause it to be innefficient in its triggering.

Build it to spec if you want the best results, then build others different to test/compare. Ceramics are nice and cheap these days anyways

Good luck

[Nostradamus2]

can someone explain (or give me a link) why ceramic magnets must be used?

I think because they have different BH curve and slower lag time, neos are more "harder" and they have faster lag. If you decide to use neos then you must construct the Bedini wheel to rotate at higher rpm.