[sdiy] Wrapping directions for pickups - polarity and such

[rkmoore at memphis.edu]

I don't have much experience with pickup winding, but I did make some 
large solenoids recently for a piano noise-making project.  

I would suggest that you make a series of small (probably single 
magnetic pole) pickups that can be mounted next to each other along 
the harp.  If you do it this way it will be easier to trace down a 
wire break in the pickups.  If you make one monster pickup and the 
wire breaks at the coil start end, or inside the pickup, then you have 
to start from scratch.  Also, if you are winding small coils that are 
mostly cylindrical, it's fairly easy to rig up a variable speed hand 
drill to do most of the winding; making it neater, easier, and 
quicker.  Another advantage will be that you will be able to move the 
small pickups individually and experiment with different phasing 
configurations.

Good luck, and let us know how it turns out.

Richard Moore

----- Original Message -----
From: Robotboy8 at aol.com
Date: Monday, March 7, 2005 9:28 pm
Subject: [sdiy] Wrapping directions for pickups - polarity and such

> I'm in the process of constructing a simple electric harp.  In all 
> a very 
> simple project with one exception: it requires a foot-long pickup 
> with custom 
> magnet spacing.  Not difficult to make but tedious as all hell to 
> wind.  So what 
> I'm wondering is how necessary it is that the wire go around the 
> magnets in 
> the traditional direction
> (beware ascii picture)
> /-----------------------\
> |000000000000000I
> \-------------------------/
> 
> as opposed to wrapping around the magnet lengthwise.  In other 
> words, will 
> the pickup work (and if so, how well) if the wire were wrapped 
> around the 
> foot-long bobbin such that the smallest diameter were made, rather 
> than the largest. 
> And if that works, will it be better to have it come back over 
> and cover 
> itself again and a third time?  Wrapping front to back, then back 
> to front, then 
> front to back again?
> 
>       -eric, apologizing for how hard it was to phrase this question
>