The Oil City Masterwound PAF-Alike thread

impmann

Interesting you mention Page.

His No1 Les Paul hasn't had a PAF in the bridge position for most of its time with Jimmy. Initially it was replaced by a T Top and I believe it currently has a Seymour (custom wind).

OilCityPickups

Indeed ...

xJonnysixstring

Thats the official story anyway Im sworn to secrecy!

impmann

I bet it's an Epi pickup based on that!!!

OilCityPickups

Right on with the good stuff :-)

50s PAFs were made with Butyl Butyrate bobbins. This was an early plastic compound with a different look and feel to modern bobbin materials. Looking slightly dull and matt compared with shiny modern thermoplastic bobbins, they are harder, bore brittle, and have an odd 'chemical' smell to them.

For my accurate reproductions of 50s pickups I use Butyrate bobbins modeled from 3D scans of originals.

Does it make any difference to the sound? Not that I can detect ... but it certainly makes the pickups look the part ... especially if you chose 'uncovered' as an option. There hardness may have a small impact on sound ... but to be honest I personally can't hear it ... and I have pretty good ears.

Below a Butyrate bobbin top view

and side view

Here is the side view of a modern bobbin for comparison. As you can see there is considerably more 'fresh air' inside and this may be another reason for original PAFs to be more resistant to feedback even when unpotted.

more on wire shortly

OilCityPickups

Right on to winding wire now. A subject about which more absolute rubbish is talked than anything else.

Firstly all copper wire of the same gauge is the same, and wire doesn't have a sound of its own anymore than a brick has a characteristic mating call! The differences in sound from different winding wire types are all due to the coating that is added to insulate them. In the 50s Gibson used PVA coated plain enamel wire with a coating of various shades of dark brown down to almost black.

PVA coated wire is an absolute bitch to work with, the insulation being delicate and prone to crack at the bobbin ends if the wire is stretched during winding. It does however 'lay' on a bobbin differently to modern poly coated wire which has a much more robust insulation. 

It is this different characteristic of the space the coils take up on the bobbin and the way they overlay each other  that is key to why PVA sounds slightly, and subtly different to poly. Note, I didn't say better ... because poly in fact suits many modern pickup designs better than PVA.

Below: a roll of PVA plain enamel wire on my bench with some 60s style Strat bobbins/flatwork

By the way, I hesitate to call PVA coated wire 'plain enamel', as most modern wire manufacturers call their poly coated wire 'plain enamel too. Plus you can get poly wire in the same shade of brown as old PVA to add to the confusion! 

Gibson switched from PVA covered to poly in the early sixties for the T-Top humbucker ... and Gibson has only in latter years started using PVA again in it's own PAF style pickups.

The down side of PVA is it's very high cost compared to modern poly wire, and its very limited availability. Our stock comes from the US.

Cabicular

really interesting

I have two R9 Gold tops 

one of them is painfully microphonic at the bridge pup. I play at reasonable gain so expect a bit and normally rolling the volume off a notch is enough to keep it under control. This one doesn't stop squealing til I have it at 4. Before I get the double boiler out of the cupboard is there anything I can tighten or check?

P.s. I'll PM you about an HSH set for a Jackson

OilCityPickups

Cabicular said:

really interesting

I have two R9 Gold tops 

one of them is painfully microphonic at the bridge pup. I play at reasonable gain so expect a bit and normally rolling the volume off a notch is enough to keep it under control. This one doesn't stop squealing til I have it at 4. Before I get the double boiler out of the cupboard is there anything I can tighten or check?

P.s. I'll PM you about an HSH set for a Jackson

Hummmm I am going to do a photo story about going inside a modern Gibson Humbucker shortly ... from a repair I did the other day. Sadly the quality of the bobbins and the very wide tolerances generally was a bit of an eye opener. That particular pickup had been factory potted ... if it hadn't been there was little chance it would have been anything but a 'squealer'. 

Do the obvious and tighten the bobbin mounting screws a smidge ... and make sure you haven't got a loose pole screw ... but aside from that I would bet on it needing a pot.I tend to put a bit of cloth tape on top of the bobbins before putting a cover on with a pickup that is to be left unpotted. This helps deaden out the vibration and take up any air gap.

I think that double boiler will need to come out. 

Just a tip ... drain them after potting upside down ... that way the waste wax takes up any air space on top of the bobbins rather than simply running away down the pickup legs!

ddlooping

Very informative thread, Ash, thanks for sharing.

impmann

Seconded!

Cabicular

Thanks

Evilmags

Very cool. Looks very like the ASL custom shops in my arch top. Which are stunning pickups.