Trade Secrets!

How to open a humbucker and reverse the polarity


Issue 69 September 04, 2008

How do you pop open a humbucker?
Ever try to open a humbucker?
This Trade Secret is about switching a humbucker’s polarity, but the hard part is getting the doggone pickup open!

Erick Coleman signature Erick Coleman,
September 4, 2008
Photo: Erick Coleman
Frequently Asked Questions
A customer called the other day with a simple wiring question.
He had two 4-lead humbuckers to use with our PRS wiring kit. The kit instructions call for one of the pickups to have opposing magnetic polarity. That's easily achieved by pulling and flipping the magnet this way:

Photo: removing the humbucker's magnet

1 ) Loosen the polepiece screws so they clear the baseplate, then loosen the bobbin screws a bit so the magnet slides out ( 2 ). Be careful so you don’t damage any of the delicate connection wires.
3 ) Roll the magnet over, flipping it 180 degrees. This is the move that switches the polarity.



Humbucker Bobbin Mounting Screws
Guitar Tech Screwdriver Set



Humbucker Bobbin Mounting Screws
Humbucker Bobbin Mounting Screws



Humbucker Alnico V Magnet
Humbucker Alnico V Magnet



Covers For Humbucking Pickups
Covers For Humbucking Pickups



Cam Clamps
Cam Clamps



Humbucker Kit
Humbucker Kit
Photo: replacing the humbucker's magnet
Re-install the rotated magnet, sliding it back where it came from. Simple enough, right?

That’s how I described the job to the customer. But then he asked, “But how do I get the darn cover off?”

Let me show you how I do it...
Removing the cover from a humbucker can be tricky.
Generally, the cover is soldered on. Removing it is even a little risky, because it’s easy to damage the coil (don’t ask how I know!!!). To do this you’ll need two clamps, a razor blade and a soldering iron.
Photo: clamping the humbucker
I like to hold the pickup in a cam clamp while I’m working on it. The cork lining in the jaws doesn’t mar the plating.

While your soldering iron heats up, insert the corner of a single-edge razor blade between the cover and the baseplate of the pickup.

Photo: desoldering the humbucker cover
It only takes a touch of the hot iron to melt the solder. As soon as it does, carefully work the blade between the cover and baseplate just enough to keep the solder joint apart while the solder hardens.

When the solder cools, the blade slides right out. Do this on both sides, of course.
Photo: removing the humbucker cover
The cover is now loose and ready to come off.

After flipping the magnet, it’s time to put the cover back on. But is that really what you want to do? Here’s a decision to think about:
Photo: covered humbuckers
Golden Age Humbuckers
with gold covers


Photo: exposed humbucker coils
Golden Age Zebras
with exposed coils



Cover your pickups or let them run around naked?

Since the cover itself creates some capacitance, it can take the edge off the sound of the pickup. Some players prefer the brighter sound of an uncovered pickup, so they leave the covers off. That’s why we offer our Golden Age Humbuckers in no-cover versions like the "Zebra" at right.
Photo: clamping the humbucker cover
For those of us who like the sweet sound of a covered pickup, here’s a quick way to put it back on.

I use a mini cam clamp to make sure the cover fits to the pickup as tightly as possible.



Mini Cam Clamps
Mini Cam Clamps



Wiring Kit for Paul Reed Smith
Wiring Kit for Paul Reed Smith



Magnet Polarity Tester
Magnet Polarity Tester
Photo: clamping the humbucker cover
I’ll then use my medium clamp to bring the sides in tight against the baseplate.
Photo: resoldering the humbucker cover
When the sides are clamped, remove the mini cam. A quick touch of a hot soldering iron will flow the existing solder together and secure the cover back in place.
Photo: reversed-polarity humbucker
When the solder has cooled, remove the clamp and your reversed-polarity pickup is ready to wire up in PRS fashion!
Erick Coleman signature

Problem-solving products mentioned above:
Photo: Magnet Polarity Tester Photo: Humbucker Kit Photo: Guitar Tech Screwdriver Set
Magnet Polarity Tester
A very useful tool for troubleshooting and testing pickups and wiring.
Humbucker Kit
Assemble and wind your own humbucking pickups with our vintage-style kits.
Guitar Tech Screwdriver Set
Our versatile 19-in-1 set especially for fretted instrument hardware. A Stewart-MacDonald exclusive.
Buy Now
Buy Now
Buy Now
Photo: Mini Cam Clamp Photo: Wiring Kit for Paul Reed Smith Photo: Cam Clamps
Mini Cam Clamp
A lighter, slimmer cam clamp for working on guitars and smaller instruments.
Wiring Kit for Paul Reed Smith
Rotary switch with all the components for wiring a PRS guitar. Complete with a wiring diagram.
Cam Clamps
Cam clamps are a favorite of all types of woodworkers and they come in very handy in lutherie as well. We offer high-quality clamps in two sizes.
Buy Now
Buy Now
Buy Now

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