Pickup Magnets

wackojacko

Can anyone give me a basic run-down of what the different pickup magnets actually do to a pickup.

I want to get one of those DIY pickup kits for a project/partscaster and fancy a go at doing the pickup....

So whats the difference between Alnico 2,3 and 5 etc...?

Alegree

3->2->5 in strength
Lower strength = more mids, softer treble, looser bass.
That's a over simplification, but it's the basics.

I sell those pickup kits you're after.

Funkfingers

The Alnico formulation numbers represent differing percentages of Aluminium, Nickel and Cobalt used in the magnet material. 
Trying to associate a particular formulation with a specific guitar tone is over simplistic. There are numerous other variables to consider. 

If you propose to build your own humbucker, it is simple to change the bar magnet. You can try out several magnet formulations until you find one that satisfies.

If you propose to build a traditional single coil pickup that employs fibreboard plates and individual rod magnet polepieces, you have to commit to the formulation(s) before the coil is wound on. 

A more practical alternative might be to use a plastic single coil bobbin similar to the modern Fender type. These physically separate the coil from the magnets. It is possible to move the individual magnets without damaging the coil.

On single coil pickups with individual rod magnets, there is nothing to stop you mixing and matching formulations per polepiece. One of my favourite mass production single coil pickups is the Seymour Duncan Five-Two. A5 keeps the EAD strings nice and twangy. A2 smooths out the GBE.