Quаdrail pickup question

[chrisstoyanov]

Hello friends!
I bought from Amazon and want to install a quad-rail pickup in the bridge position. Unfortunately, while hot-waxing it, the middle magnet fell off. I quickly put it back, but now I question myself, if i messed up the polarity. There are 2 ways to put the middle magnet in and I think I should be put in such a way that the poles oppose the 2 neighboring magnets:

SN|NS|SN

My concern is that I put it back in the slot the wrong way:

SN|SN|SN

The middle magnet is firmly stuck in the slot, not even sure how to pull it back, if I have to.

Any advise on how I should restore the middle magnet and to verify if I did it correctly (I do have a compass)

[pyrroz]

hey dude

Dobrodosli na nas forum, priyatelyu!!

Are you from Sofia, BG right, or other part of Bulgaria?

Ok, here is the thing, if the pickup *originally* had the correct polarity (inside coils) and also the correct winding (phase) then , after you messed around with it there are two possible cases:

a) wrong polarity (noise), wrong phase (weak sound)

b) correct polarity (noiseless), correct phase (in-phase, full sound)

so, you won't miss it!

hmmm still not sure about the magnet part... maybe I am missing it. You better pull it out again and try both ways.

[newey]

Dec 13, 2021 8:31:57 GMT -5 pyrroz said:

You better pull it out again and try both ways.

He said he couldn't get it back out again. A compass might tell the tale, but with the three magnets so close together, it may be tough to tell if the middle one is opposite the other 2. You can also use your computer to test it:

guitarnuts2.proboards.com/thread/4938/testing-phase-screwdriver-pull-test

[reTrEaD]

Dec 9, 2021 19:24:18 GMT -5 chrisstoyanov said:

Hello friends!
I bought from Amazon and want to install a quad-rail pickup in the bridge position. Unfortunately, while hot-waxing it, the middle magnet fell off. I quickly put it back, but now I question myself, if i messed up the polarity. There are 2 ways to put the middle magnet in and I think I should be put in such a way that the poles oppose the 2 neighboring magnets:

SN|NS|SN

My concern is that I put it back in the slot the wrong way:

SN|SN|SN

The middle magnet is firmly stuck in the slot, not even sure how to pull it back, if I have to.

Any advise on how I should restore the middle magnet and to verify if I did it correctly (I do have a compass)

Since the middle magnet fell off, we can make an educated guess that the magnets almost certainly were in this configuration to begin with:

|SN|NS|SN|

There's an inherent physical instability where the like poles are repelling. Whatever was holding the middle in place was compromised during the wax-potting. If the middle magnet was in the orientation you currently have, it wouldn't have fallen off.

I don't see the middle magnet as even being necessary. All four blades would be magnetized with just the outer pair of magnets. Not sure why they chose to use a magnet in the middle.



I'll tag antigua, as he's had his hands a ton of unusual pickups. Perhaps he's seen this one and can shed more light on the subject.

[chrisstoyanov]

Thanks reTrEaD - Yes, I think SN|NS|SN was the correct original position, IMO too. Part of the reason to think this way, is this educational video.
(You can see the particulars of this quad-rail by clicking the Amazon link I provided above)

Thanks newey - yes, it is hard to pull the middle magnet, but I can try harder. The worst thing that can happen is destroy the pickup, a $15 loss .. oh, well.

Thanks pyrroz - yeah ... Sofia, BG --->Irvine, CA, USA.


Thanks all ... got really carried away with guitar mods having done none before .. as a result ... a few of my guitars lay gutted on the table, gotto finish them before the year is over (My hobby 2021 resolution!)

[antigua]

Dec 13, 2021 9:51:03 GMT -5 reTrEaD said:

Dec 9, 2021 19:24:18 GMT -5 chrisstoyanov said:

Hello friends!
I bought from Amazon and want to install a quad-rail pickup in the bridge position. Unfortunately, while hot-waxing it, the middle magnet fell off. I quickly put it back, but now I question myself, if i messed up the polarity. There are 2 ways to put the middle magnet in and I think I should be put in such a way that the poles oppose the 2 neighboring magnets:

SN|NS|SN

My concern is that I put it back in the slot the wrong way:

SN|SN|SN

The middle magnet is firmly stuck in the slot, not even sure how to pull it back, if I have to.

Any advise on how I should restore the middle magnet and to verify if I did it correctly (I do have a compass)

Since the middle magnet fell off, we can make an educated guess that the magnets almost certainly were in this configuration to begin with:

|SN|NS|SN|

There's an inherent physical instability where the like poles are repelling. Whatever was holding the middle in place was compromised during the wax-potting. If the middle magnet was in the orientation you currently have, it wouldn't have fallen off.

I don't see the middle magnet as even being necessary. All four blades would be magnetized with just the outer pair of magnets. Not sure why they chose to use a magnet in the middle.



I'll tag antigua, as he's had his hands a ton of unusual pickups. Perhaps he's seen this one and can shed more light on the subject.

Yeah, you're right, the middle magnet will naturally want to pop out because it's correct orientation is N on N and S on S, so that the orientation of the magnetic field within the steel pole piece itself will be N and S respectively. If you line them up [SN][SN][SN], then the steel pole pieces will null out, and that will kill the pickup, so that would be a lot worse than just leaving the middle magnet out. You would know if you were putting it back correctly if the magnet tried to pop back out, so you would have to use some sort of adhesive or whatever to keep it in place. 

The middle magnet is sort of unneeded, but it will make the magnetic field a little stronger at the strings which might influence the tone, adding a little more treble.