Anyone have a single A1 and or C5 bucker magnet?

[belwar]

Does anyone have an A1 and or C5 humbucker magnet? I'm putting together a chart of real world guass readings and inductance changes with different mags. I've got A2, A3, A4, A5, Iso-A5, A6, A8, A9, C8, and Magnet Steel. I'll gladly flip you some money for it plus shipping. Looking for long magnets .5 x 2.5 x .125.

Let me know, and i'll be happy forever!

bel

[David King]

I might have some c-2 from a very bad sounding Chinese strat but it's the wrong dimensions. I've never heard anyone mention A-1 before, I figured it didn't exist.
I've been told that C-5 is nearly indistinguishable from C-8 but hopefully someone will come through with a sample.
Do you have a way to charge the ceramics up all the way?

[belwar]

I have one of those nice electrical magnetizers.. Big ones that when you flick the switch the lights in the whole place dim. :> cost me a few hundred but I love the thing.

I figured it might be a challenge to find A1, but it's worth a try. What dims would your C2 be?

[tonedeciple]

How funny. I just started a new thread asking for ideal gaussmeter readings for different magnets. I don't have what you're looking for (A1/C5), but I'd love to see your chart when it's done.

[Possum]

...

Its kind of pointless. All you can do is measure each manufacturer's grade of alnico, physical mass size, charge it fully and then get a measurement. Ceramic magnets are no different, they are probably charged en masse like they all are and some get charged hot and some don't. I have some bitchin' A4 rough cast magnets that charges to 700 guass, you would expect only alnico 5 to hit that high but these are real A4 and sound like A4, so how does that fit in with a generic chart? I also have other A4 that will only hit 575 gauss which is more typical but this is from another company; alot of my A2 will only charge to about that same gauss. You can't really make definied categories that everything fits neatly into, though I wish it were so...

[RedHouse]

Its kind of pointless. All you can do is measure each manufacturer's grade of alnico, physical mass size, charge it fully and then get a measurement. Ceramic magnets are no different, they are probably charged en masse like they all are and some get charged hot and some don't. I have some bitchin' A4 rough cast magnets that charges to 700 guass, you would expect only alnico 5 to hit that high but these are real A4 and sound like A4, so how does that fit in with a generic chart? I also have other A4 that will only hit 575 gauss which is more typical but this is from another company; alot of my A2 will only charge to about that same gauss. You can't really make definied categories that everything fits neatly into, though I wish it were so...

Doing metrics is never pointless, the trick is useful application of the data.

[kevinT]

I did something like this about 4 years ago.

info on magnet gauss levels

[belwar]

Cool!

The chart im making includes gauss readings of the mag fully charged, then I placed each magnet in the same pickup at @ 70 degrees and took inductance readings at 1khz. I also took gauss readings from a slug and a screw.

It lets you see the inductance / gauss differences between mags.

So far the biggest shocker was the inductance difference beween C8 and A8/A9.

bel.

[Possum]

....

The only use of this will be for that magnets that you already have. My A4 using this method would be misidentified as alnico 5. It also only works on magnets that you personally charge in a real magnet charger, as well. I don't quite see the point of doing this Not to mention that reading gauss straight off a fresh charged magnet is also faulty because over a couple of days it will drop some.

[belwar]

Its kind of pointless. All you can do is measure each manufacturer's grade of alnico, physical mass size, charge it fully and then get a measurement. Ceramic magnets are no different, they are probably charged en masse like they all are and some get charged hot and some don't. I have some bitchin' A4 rough cast magnets that charges to 700 guass, you would expect only alnico 5 to hit that high but these are real A4 and sound like A4, so how does that fit in with a generic chart? I also have other A4 that will only hit 575 gauss which is more typical but this is from another company; alot of my A2 will only charge to about that same gauss. You can't really make definied categories that everything fits neatly into, though I wish it were so...

All the A4 i've had measures above A5.

[salvarsan]

All the A4 i've had measures above A5.

A magnet's resistance to demagnetization, (coercivity or Hc) matters a lot for short alnico pieces, especially in comparison to ceramics and rare earth magnets.

The official spec sheets tell you the limiting magnetic strenth (remanence = Br) of an alloy. If the piece is shorter than the critical dimension, you won't see the maximum gauss. The coercivity property, Hc, quantifies this behavior.

For the small sizes that pickup makers use, high coercivity magnets are stronger than lower coercivity ones even though their limiting strength is less.

Although it's limitiing strength is half that of A5, Alnico 4 is 10% more coercive. That's enough for it to be the stronger magnet in a PAF size.

-drh

[Possum]

....

I have A4 that charges to 700 gauss, my A5 charges to that or above at 750 guass, but I also have A4 that charges to 550, all are the same bucker size.

[EFK]

Hey where did you get that A4? I've got A4 from Allstar that regularly charges to 700-750 gauss off a big neo brick, and it is some *spectacular* stuff! Never heard anything like it other than genuine old pickups. I think Arnold Mag's A4 will go that high as well.

[RedHouse]

I have A4 that charges to 700 gauss, my A5 charges to that or above at 750 guass, but I also have A4 that charges to 550, all are the same bucker size.

That's good, we should document that

[Possum]

...

The low charge A4 was from Earth Panda, I had a contact there who got married and no one replies to my RFQ's there anymore. Their stuff was real different, all very warm, low energy stuff. Its been five years now, their stuff could be radically different. My strong A4 is also great stuff, a custom batch of rough cast....