Inside a mid 60'd bass pickup

[Murphman]

HI all,

Well this is my first real post ( hope it's in the right section? )

I've been rewinding / repairing here in Sydney, Australia for 10 years or so. A few years back 2 Mosrite bass pickups ( or what was left ) were sent for rewinding. I took the opportunity to snap some photos before I rewound one bobbin and made a matching one.


I was amazed at the crudeness of the construction and the black and clear resins used.



As a toolmaker by trade I could tell that some money had been spent on tooling - the aluminium height bar had been stamped out as well as the clear acrylic bobbin ends ( die cut ) then there was all these "hand made" aspects to them... wow!!!!



Four nuts set in resin under that brass foil - and then those segmented magnets!


Funny thing is that the magnets are charged "on edge" NOT end for end ( like a normal bar magnet ) or through the flat surface ( like as if you would use them to stick to a metal surface ) so what were they off??



Anyway, hope this is interesting for some .....

Cheers!

[maxkat]

Hey Murphman,
great photos and descriptions, thanks a lot!
Cheers, Max

[Veenture]

Excellent!

[Murphman]

Thanks guys, it appears the pickup construction changed a bit in the early days. As well as this crude style there have been ones I have seen where the brass foil has been replaced by a brass plate, then instead of nuts, the plate was threaded to fit the screw polepieces. The thread stuck through the plate and then the magnets touched the screws and were held in place with resin epoxy.

Construction in the 70's & 80's changed again - but that's another story!

[MWaldorf]

Cool - thanks for sharing. I'm curious, what are the pieces of tape in the wire windings above the second pole to the right? Are those splices, or for some other purpose, or just to made future investigators wonder?

[Murphman]

If I remember correctly ( and it WAS some time ago ) it was the same tape that the bobbins are wrapped in but I think the wire had been broken, re-soldered and taped over. Knowing how weakand easily broken 43# wire can be, I'm not surprised breakages while winding happenned. Adds to the "folksy" handmade aspects ( and the coil doesn't care if theres a few patches internally - it will still work!)

Dan

[Dennisthe Menace]

WoW!! I've never seen a Mo' p'up with the round metal inserts in place of the screw pole pieces.
The only type of guitars/basses I've seen those on were 60's Japanese instruments such as the
Univox Hi-Flyer, Aria's and others as well from that era....very interesting .

[Murphman]

Hi Dennis,

No, these has the 6-32 screws for polepieces just like normal, they just screwed into the nuts that were set in the resin ( under the brass foil and between the magnets - you can't actually see them )
The bobbin has holes drilled ( roughly ) at the 4 spacings and the holes are large enough for the heads of the screws to pass through.
Good ol' contact glue holds the cover to the bobbin and the bobbin to the foil / magnet base.
I'm sorry I didn't do more photos but I never knew I'd be posting them for others to see years later!

[oipunkguy]

i know on mine humbuckers common scatch tape was used to hold the magnets to the base plate. pretty high tech huh? lol

[raygun85]

The tape in the middle between the winding was probably where they had a break while winding and resoldered it back together. If the windings aren't too loose, it isn't absolutely necessary to wrap them before continuing on. But if they're a little loose, they might have a tendency to want to start unravelling. Hence the tape. It could also indicate that the coil had been underwound and more wire added before assembly (especially before soldering the lead to the finish wire. I'm speaking purely from oersonal experiences.

By the way, Mel, your pickups have a piece of cloth tape between the inner coil and the outer coil.