Properly grounding and shielding your pickups

[shawnl]

Now that I've been winding for a few months, I have a stockpile of different pickup designs I'm getting ready to test. I want to make sure I understand how to ground them properly. Now everything about my pickup designs are entirely handmade. They are blade poles with thin plywood bobbins and mounting plates. I'm wondering if having wooden base plates is a bad idea because I don't really have any solid metal to ground to other than the blades, which are not accessible once the magnets are installed. With that in mind, is it enough just to cover the bottom in copper shielding foil and solder a ground wire to that or is it essential that the blades themselves have to be grounded?

[shawnl]

I just saw some threads relating to this. I think I understand how to accomplish this. So essentially, I cover the magnets with copper foil (containing conductive adhesive) as though I'm taping them in and then solder a wire to the foil. This wire will eventually solder together with the negative/ground wire of the pickup once it reaches the lug of the potentiometer during installation.
Am I understanding this correctly?

[David Schwab]

I stick the copper foil to the magnet/blades and this goes to the drain wire in the 4-conductor cable I use. I would not connect it to the pickup coils because then you can't change the polarity if you need to. If you aren't using 4-conductor cable, use 2 conductor plus shield.

[David King]

In my experience the conductive tape connection doesn't hold up over the long term. You need an additional physical connection like a spring's pressure or a tightened screw head to maintain a reliable ground.