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P90 Mags

2/10/2004 3:34 AM
P90 Mags
Up to now, I've just been winding Humbuckers. This evening, I had a request from a fellow that I sent one of my buckers to. He's asking me to re-wind a P90 for him. This will be my first of this type, and I figured that the magnets were different shape/size - based mainly on the pictures in Jason's book (shows two small mags per pole piece). I don't see these on SK's supplies list, so I'm wondering if this is how y'all wind them, or are you using the long bar magnets. Can anyone fill me in before the PuP(s) arrive for the rewind?  
I figure it's got ceramics in it, so I'll put A5 in with 42 PE. I have some bucker bars.
2/10/2004 6:01 AM
I think you'll want two humbucker bar magnets - both having the North pole against the pole pieces.
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2/10/2004 10:08 AM
Dave Stephens
Or south pole most likely. If both pickups are humbucking in the middle switch position one will be north the other will be south and the lead wires will be switched or the coil reverse wound....Dave
2/10/2004 6:12 PM
SK Use HB bars
same size, The difference is the keeper bar on a P-90 *may* be a little narrower. The pic in Jason's book is "misleading" for a traditional P-90
2/10/2004 7:52 PM
Jason Lollar

You have to remember parts of that book are quite old and I am a product of Semi Mosely so that particular drawing is very close to a moserite but the dimensional drawing in back shows the gibson magnets.  
the gibson magnets are still harder to find than alnico rods but back then they were practically impossible to find unless you bought 500 and in many parts of the world are still hard to come by so the segmented magnet stucture drawing remains.  
I made them that way for years!  
Anyone thats only started up in the last 4 years or so has no idea how good you have it as far as getting parts, youre spoiled :)
2/10/2004 9:39 PM

Thanks guys. I re-read the section awhile ago, and notice that you mention bar magnets in the text, and there's a drawing later on that shows them. I still want to be sure on the orientation though.  
Both South poles facing or at the pole pieces?  
Also, I didn't think about the keeper. I can use a bucker keeper?  
Thanks again.
2/11/2004 2:12 AM
Sheldon Dingwall
It's been decades since I've had a P-90 apart. What are you calling a "keeper".  
Jason, is there any difference in tone or performance between a P-90 with rods vs one with bars?  
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