WRH / TB Pickup Project: Magnestism and Grounding Questions

[Man@Large]

Hello. I am trying to build a set of pickups with the construction features of the original Fender WRH and the Travis Bean humbuckers / single coils.

Some crucial background information can be found in this thread:

http://music-electronics-forum.com/s...ad.php?t=10136

For my first attempt I am modifying some coils (from a P90 and a PAF-style bucker) to accept some A5 rods. I have the resources to build the necessary baseplates.

Most of my questions concern installing/charging the magnets.

1.) I ordered a set of neo-mags from Stewmac to charge the alnico. How do I determine the polarity of disk magnets?

2.) Is it best to magnetize the alnico after the coil is completely assembled?

3.) How should the magnetism be oriented (N out vs. S out)? Should the magnets be charged the same way for each coil in a humbucker, or is it better if they are opposite?

4.) If it doesn't matter which way the magnetism goes through the rod, will I even need to determine the polarity of the disks?

5.) Will it create any problems if I powdercoat the baseplate?

6.) How will these need to be grounded?


Thanks!

Kind regards,
Matt

[Man@Large]

Just wanted to bump this up and add a couple of pictures. I'm ready to pot these, but I still haven't charged up the Alnico.

Is it as nuanced as it seems? Is there more than one way to do it?

I am mostly concerned about the humbucker and whether or not the polarity needs to run differently in each coil.

Any help will be greatly appreciated. Unfortunately I am in sort of a hurry; trying to get some guitars to the Columbus show in January.

Thanks!

[Spence]

Yes the magnets need to have opposite polarity in each coil but the coils must be wound in the same direction. If you have any other questions regarding the way a humbucker works and you can't find it here by all means send me a PM.

[Man@Large]

I finally installed these pickups, but there are some complications that I haven't identified yet.

This sounds like a grounding problem, but if there's a chance that it's the pickups I thought this would be the place to find out.

Here's the setup:

P90 - Neck
Humbucker - Bridge (4-conductor)

2 Volume
2 Tone
3-Way Toggle

There is output, but the tone controls don't seem to work at all. The volume controls only cut the volume in and out (between 0 and 1) and offer no variance.

I wired the guitar the same, reliable way I have wired all of my other ones. What sounds like the problem?

Thanks.

[Man@Large]

And photos...

[paulyy]

Your pickups sound like they might be ok. They could be out of phase but I cant be sure with out hearing them. It could be the way your pots and switch are wired. You said it sounded like a grounding problem. Try seymourduncan.com. He has all kinds of wiring digrams. look under suport and youll see wiring diagrams. If that dosent help, Im sure someone on this forum can help you.

[Man@Large]

Would a phase problem affect each pickup even when only one is selected?

Both of the pickups sound very week and almost a little bit distorted. The output is very low.

[paulyy]

Nice wiring. maybe you dont need any wiring diagrams after all, but it doesnt hurt to look. The body looks like some type of metal, not wood. what is it.

[paulyy]

Would a phase problem affect each pickup even when only one is selected?

Both of the pickups sound very week and almost a little bit distorted. The output is very low.

Ive had this problem before. Try swaping the hot and ground wire on both pickup. One at a time. I had a SD pickup that I wired in with fender pickups and I got what you were getting. SD will tell you on his web site to swap out the hot and ground. It sounded fine after that.

[Man@Large]

Thanks, man.

So, if there is a hot/ground problem, is it probable that this can "infect" the rest of the wiring and explain the problem for both pickups?

The body is aluminum. It's part of a fairly complicated assembly process; I want to be close to the problem before I crack the thing back open

[paulyy]

Thanks, man.

So, if there is a hot/ground problem, is it probable that this can "infect" the rest of the wiring and explain the problem for both pickups?

The body is aluminum. It's part of a fairly complicated assembly process; I want to be close to the problem before I crack the thing back open

No problem. Give it a try and hear what happens. You cant hurt any thing trying.

[Sol]

I just did this recently.

Make sure you wired the output jack correctly (i.e. make sure the hot is hot and ground is ground)

If the jack is wired backwards, volume will kind of work but tone will not, and the aluminum body of the guitar will sort of act like a receptor, so the sound will be crackly like there is a grounding problem.

paulyy suggestion would solve this...but your wiring is amazingly neat. Check the jack, if thats correct, then try Paul's suggestion.

I wish I could do wiring like that....

s

[David Schwab]

And photos...

That's very neat wiring! I see you are using coax between the pots, but I don't see the braid grounded. If it's not grounded it wont work as shielded wire, and may introduce more noise.

[David Schwab]

Would a phase problem affect each pickup even when only one is selected?

Both of the pickups sound very week and almost a little bit distorted. The output is very low.

I don't see the wires from the pickups in that photo. Do you have the grounds connected in the circuit? What value are the pots?

I'm thinking you have missing grounds, which is why the tone controls don't work, and maybe the pickups low output too.

Did you get the magnets charged correctly?

[Peter Naglitsch]

This:

The body is aluminum.

will of cause shange everything when it comes to grounding, ground loops, the need to ground the braid of coax cables etc.