Diagnosing Weak '60 PAF

Discussion in 'Pickups' started by jdmp, Oct 22, 2017.

  1. jamman

    jamman Premium Member

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    Thanks Rudi , Hopefully he can work out the problem without shipping the guitar back to the USA . IMO , seems like a long trip for an issue that's not so big , it would need that ... even if it's only diagnosed to find the problem at 1st. seeing if it truly needs that , imo would serve the OP better . With all the CITES issues now , problems are just waiting for the unsuspecting ... :Ohno:

    :cool2::cheers2:
     
  2. zoork_1

    zoork_1 Senior Member

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    I've never own a T-top, Patent No or PAF with an ok reading that couldn't be brought to life.
    First thing I would do is to check/charge the magnet.

    +1 to James (ReWind) for good advices.
     
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  3. RAG7890

    RAG7890 Premium Member

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    John has sent the PU to James, which is a great option IMHO.

    I'm looking forward to hearing what Jame's take on this one is, re Magnets or just not a good PU.

    If it is not a good PU, I'd be looking at playing with some Magnets.

    Good luck John / James.

    Cheers, Rudi
     
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  4. Dougie

    Dougie Senior Member

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    7.87k is plenty enough DCR to get some whompf out of a PAF. I wind my neck pups really close to that value. I find that examining a magnet with a gauss meter will reveal a LOT about how the pickup will sound in a guitar. It is quite simple. Most bar magnets are not very evenly charged across both poles, many are stronger on diagonal corners and if you use a magnet that has it's N pole facing the neck, and the meter reads 25-27 on the treble side and falls off considerably toward the bass side, this pickup will have more voicing on the plain strings than the wound, it will be louder on the treble side of the pickup than the bass side. I use the same old Gauss meter that Seymour Duncan uses and I orient the magnet according to how I can get the best voicing out of the guitar at the position I am going to use the pickup.

    So it is entirely possible that the magnet in the PAF which the OP is posting about was never really that great from the factory, or that it got weaker in the 50+yrs it has been in that guitar. As James said, Gibson was never concerned much with the DCR of what pickup went where, and they were chosen at random and installed in guitars at the factory.

    Another thing that enters the conversation is that although I cannot prove this, I have heard it said more than once that Gibson used whatever they could get the cheapest price on when it came to magnets and that they would often buy military rejects because they were available cheap. How much of this is truth and not hearsay I cannot verify but I have heard it more than once.

    Opening a weak PAF and swapping in a stronger magnet while retaining the original would not be the kiss of death for that pickup by any means if that is what it takes to enable a repair and make it sound good.

    Many years ago I was given a pair of short magnet PAFs from a 61 or 62 SG/LP that never did blow my skirt up, and obviously never did much for the guy who gave them to me either. Back then I didn't know much about pickups or magnet swaps, I often wonder what would have happened if I had swapped in some long magnets from a 50s P90?

    Not all PAFs are great sounding pickups, for whatever reason.
     
    Last edited: Nov 23, 2017
  5. backbeat1967

    backbeat1967 Junior Member

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    I had Lollar repair a 1974 original strat single coil that was on my 1974 blonde strat. He did a fantastic job. That's the closest I've come to pickup problems being solved.
     
  6. djd100

    djd100 Senior Member

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    While magnet gauss is most likely, if need be and you have to open it up, you could also check that the the coils are indeed wired in series and not in parallel, which would make it thin.

    Last, some people put stainless pole screws in them to keep the look when looking for a thinner tone, typically for the neck pup etc, just something else to check if all else fails to locate the problem.

    Good luck...
     
  7. 7844martin

    7844martin Junior Member

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    Hello.

    Check the ground wire on the bridge Gibson PAF humbucker pickup.

    Read the DC ohms resistance of the bridge pickup -now free from the guitar!!

    Wiggle the wire as you take the reading!!

    Check the bridge pickup hot wire-might be frayed, leaking to ground, near the plate.

    Cheers.
     
  8. Fretts

    Fretts Junior Member

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    If the magnet metal isn't broken or just plain bad, the original can be remagnetized. I had to get it done to one of my '69 pickups. As somebody pointed out earlier, good ohm reading but bad output could be weak or bad magnet.
     
  9. Zhangliqun

    Zhangliqun Senior Member

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    Maybe I missed someone already suggesting this but maybe the magnet is just weak and need of recharging?
     
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  10. TM1

    TM1 Senior Member

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    I'm betting the magnet is weak.. Not uncommon with an old magnet as some just don't hold their strength over the ages. But also fairly uncommon as maybe 5% of those old magnets get weak.
     
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  11. davidjudd2

    davidjudd2 Junior Member

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    i was brought a 63 335 with a similar problem. Everything measured right, but funky output. i took the plunge and pulled off the cover. it turned out the bobbins were wired out of phase. A quick job with the iron and it was back to singing.
     
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  12. cooljuk

    cooljuk Transducer Producer Premium Member MLP Vendor

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    I've seen the same. They metered fine and went out the door. I'd wager a bet this is why Gibson started using white wires for the coil starts, shortly after the PAFs (yes, white was for the coil starts for a while, before being swapped to coil finishes later, which are much more common - no idea why the change).
     
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  13. RAG7890

    RAG7890 Premium Member

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    James any updates?

    Cheers, Rudi.
     
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  14. cooljuk

    cooljuk Transducer Producer Premium Member MLP Vendor

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    Of course! I have the full info, a spreadsheet of measurements, and a gallery of photos. I was just giving the owner the opportunity to break the story.

    ...plus it's kinda fun to watch everyone's speculation and guessing about it. ;)

    Should I just share it all now?
     
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  15. RAG7890

    RAG7890 Premium Member

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    [​IMG]

    :cheers2:
     
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  16. Thumpalumpacus

    Thumpalumpacus Senior Member

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    Rudi knows his shit.
     
    Last edited: Dec 5, 2017
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  17. cooljuk

    cooljuk Transducer Producer Premium Member MLP Vendor

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    Ok, well, the PAF is still in transit back home to Australia, but I'll share some info to ease all of your minds. I think it's cool that so many people are interested in this PAF repair!

    Short story - yes, it was primarily the magnet, as many guessed.

    It was a rather weak magnet to begin with but was also only charged to a bit over half-saturation. I suspect this was always the case from the factory, as the charge was perfectly even from side-to-side (well, they are always stronger in the corners, that's the nature of magnets) and was perfectly oriented straight from pole-to-pole. It didn't appear to have been influenced by any external fields, which tends to leave a mess of a field behind. ...and is FAR less common than you might think from hearing people talk about how magnets "become weak" on their own. Not really the case for AlNiCo bar magnets in humbuckers.


    So, interestingly, there was a bit of a moment of concern when I first had a look at this pickup. It turnout to be ok, in the end, but can anyone see what made my eyes wide when I opened it up?

    [​IMG]
    [​IMG]
     
  18. ARandall

    ARandall Senior Member

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    Whats that under the bobbins??
     
  19. jamman

    jamman Premium Member

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    To me the solder looks to be up on the tape on the bobbin (it's also looks somewhat over heated ??) . I don't think that a right or good thing ...
    can't say I've taken any covers off and original PAF or vintage pups , so , I'm guessing . Just looks bad ...
     
  20. RAG7890

    RAG7890 Premium Member

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    .......................looks like the pickup had also been fully disassembled before it came to you James so anything is possible.

    I suspect that both the lack of markings on the magnet and the pickup bobbins having been previously removed from the baseplate (though not unsoldered) maybe due to someone flipping the magnet. Looks like that PAF had came from a Varitone ES model, and they were sometimes (not always) factory out of phase, magnetically.

    How does that sound James??





    :p :naughty: :D :rofl:

    Disclaimer - I received the above information from James (which I adjusted) when I was following up with him on his findings. :)

    Cheers, Rudi
     
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