Re-magnetizing a Rhodes keyboard pick up.

[GussyLoveridge]

I'm refurbishing a Rhodes piano and I pretty much the whole lowest octave of the piano's pickups have lost their magnetization.

I would like to re-magnetize them. I am thinking about making a reasonable sized electromagnet and just letting them hang out on it for a little while. I actually have no idea if this works this way.

Will this work?

Have you done this before?

How strong an electromagnet will I have to make?

Is there a better way?

 

[ccaudle]

My understanding of how magnets are typically manufactured is that the material is heated above the Curie temperature in a strong magnetic field, then the temperature is gradually lowered while keeping the magnetic field present.

I don't remember where the magnets are located on Rhodes pickups, but if they are on the bottom with metal pole pieces like most guitar pickups, it would likely be easier to just replace the original magnets than to re-magnetize them.

 

[GussyLoveridge]

They look like this:

There is a spot in this video at around 2:20 where you can see them re-magnetizing the pickups - but I'm not entirely sure what's going on.

 

[AusTex64]

I’m pretty sure you can remagnetize those pickups with other magnets. I own a 1958 Precision Bass where one string was not as loud as the rest. Lindy Fralin suggested using a magnet to touch the weak magnet, then play, then keep it up until I got it where I wanted it. Worked great. YMMV.

 

[abbey road d enfer]

That's kinda surprizing.
Typically magnets demag slowly over a period of decades. Causes for quick demag are extreme heat, physical schock or strong AC magnetic field.