Pickup Magnet Charging Question

[Andrew McSpadden]

Magnet question. When I charge rod magnets I get them in the 750 to 1000 range. When I charge bar magnets they get into the 350 to 500 range? Same grade of Alnico. I use the same set up for both with neos.

Why are my bar magnets not taking the same charge?

[Barry Daniels]

Because they have much greater mass than the rods.

[Andrew McSpadden]

Thanks Barry, that makes sense. Just to experiment I left a bar in my jig for 15 min. and it never went up beyond 450ish. Does mass limit the charge irregardless of grade of Alnico?

[Barry Daniels]

I don't know how to answer your final question, but I did have one thought. You said you left the bar in the jig for awhile. It is my understanding that you get a stronger charge if you pass the magnet across the charging magnet multiple times. I don't think that letting it sit there will increase the charge.

[Andrew McSpadden]

Thanks Barry! I will try that experiment!

[Barry Daniels]

When passing the magnet, move it in the same direction each time. Don't go back and forth because the reverse direction will sort of cancel the previous stroke.

[David King]

Andrew, I don't know the answer but it's an interesting question. What I can say is that your values are typical and your charging set up seems to be saturating the alnico mags effectively. Pulling or sliding bar magnets through the charging aperture will tend to slant the field in a chevron pattern which might have some audible effect but probably not.

[Barry Daniels]

I love the sound of a chevron magnetic field.

[Joshua Levin-Epstein]

in the morning.