Weasel's repair and rewind thread

[Das Gitarrenwiesel]

I thought folks might be interested to see some of the fascinating and unusual pickups that come through my workshop. I deal with gear from the 40s to the present day, so lots of variety. It has it's serious side, as some innovations in modern pickups can be found amongst the dead ends of evolution in the past. For example Höfner in Germany were winding humbucking coils with two different wire grades in one pickup back in the early sixties, likewise Burns guitars were making stacked humbuckers not much later than that!
Anyway, today here's an 8 string pickup - a Fender 8 string lap steel to be precise ... but heck, extended range is extended range

So here you have Leo Fender's favorite pickup ... seriously (yeah it looks like a weird harmonica.

Actually a 'trapezoid' pickup ... which is also as you can see here ... the bridge too! Inside it looks like this ...

The strings pass through the centre of the coil ... and the magnets are huge, and at either end of the coil!

The legend goes that the cardboard pickup bobbins were made from old 'clocking on cards' from the Fender factory ... and I can kinda believe it, as they are pretty roughly made!

The wire is Heavy Formvar which I have plenty of on the shelf in the shop ... but first I needed to break out my trapezoid winding jig that I made ... it holds the coil in a weird sidewise stance while it's wound


Like this ...

Then as the pickup is totally dead the old wire came off ...

And on went the new. Because of the card core, you can't wax pot, it'd just fall apart in a goo and spaghetti of wire mix ... so the brush is adding lacquer every 100 turns or so to replicate the lacquer dipping the original coil had.

Output wires added ... and to protect the coil for another 60 years or so I added some coil tape. Not historically accurate, but this 8 string will be used, not just be a display item, so gig ready is better than totally authentic.
The pickup is back on the owner's guitar now and he's delighted with the tone ... I can't but help wondering if the trapezoid is perhaps the weirdest Fender pickup ever made

 

[Concerto412]

Very cool deep-dive, always a treat to read up on early practices and historical minutiae.
I’m curious about the functional reason for the trapezoidal shape - whether condensing the coil winds on one side would alter the magnetic gauss over those strings? Or maybe the reason was more practical, packaging related?

 

[l1ll1]

Wow, super interesting!

 

[Das Gitarrenwiesel]

Very cool deep-dive, always a treat to read up on early practices and historical minutiae.
I’m curious about the functional reason for the trapezoidal shape - whether condensing the coil winds on one side would alter the magnetic gauss over those strings? Or maybe the reason was more practical, packaging related?

I wondered if it might be Leo going about the REALLY hard way of slanting a pickup ... as he did the easier way with with Tele and Strat bridge pickups. It's certainly a powerful pickup with a very wide tonal range.

 

[High Plains Drifter]

I hope that you're planning to post more because that was seriously cool and quite interesting. Thanks for sharing.

 

[Das Gitarrenwiesel]

I hope that you're planning to post more because that was seriously cool and quite interesting. Thanks for sharing.

If folks are interested, I have many of these ... I keep a photo record of most cool rewinds and all interesting custom jobs.

 

[tedtan]

I’d be interested in seeing the more oddball pickups (lipsticks, gold foils, Burns Trisonics, and even rarer models).

 

[Das Gitarrenwiesel]

I’d be interested in seeing the more oddball pickups (lipsticks, gold foils, Burns Trisonics, and even rarer models).

I have air coil winds on Burns Trisonic, Rez-O-Matic and early Höfner pickups. Lots of gold foils ... they stop working quite easily actually, then owners mess with them ... and the job gets even more difficult. All sorts of early lap steel pickups, and oddballs like trying to get an early Tele pickup out of a block of epoxy that someone had 'potted' it in!

 

[tedtan]

That’s the kind of stuff I’m talking about.

 

[Edika]

That was a really interesting read and I would love to read more bout other pickups you worked on!

 

[Concerto412]

I’ve always held a bit of mystique around the old TriSonics, that would be a fun read I’m sure!

 

[crushingpetal]

That was insanely cool. Thanks.

 

[Das Gitarrenwiesel]

Okay if we are ready for more from my workbench, then let's bring on a Burns rewind as requested This is from a really fascinating instrument that had a Burns stacked humbucker in the neck! Similar to this

So here is the sad and rather dead pickup .
cover off and you can see why the Rez-O-Matik and several other Burns pickups like the Tri-Sonic are so different to practically everything else: firstly there is the split ceramic magnet array in the middle ... and around it ... the coil. Yep, no bobbin. The coil was wound on a sort of 'basket' wire former ... potted, tape wrapped then pushed over the magnet. It's a total nightmare for a rewinder ... but we will get there.

Below: you can see the rock hard and very dead air coil out of its slot.

This was slightly larger than air coils I’d rewound before like the Tri-Sonic, so I had to build another tool to do it …
Below: Out with the pencil and paper to design a former for the coil ... I specialise in fast 'back of a cigarette packet' style drawings!

Now to think of how to build it ... over a mug of 'builder's tea ... I do my best thinking with a cuppa …

The 'cigarette packet' stage doesn't last long ... I whistle out a 2D drawing program and get stuck in. On screen is the central 'core' of the former .. the little 'bumps' will stop the wound coil sticking on the core ... and provide a gap for me to pass tape through.

And as if by magic ... er well ... laser

Part two with the winding bit coming up shortly

 

[CanserDYI]

More of this please!

 

[Das Gitarrenwiesel]

More of this please!

Above: nearly ready to wind ... note the layer of tape on the core ... sticky side outwards ... this will stop wire sticking in the former joins ... and make it easier start the wrapping process for me.

After ....

A few years ago when I was doing this photo set, I used ordinary 42awg wire ... I have since started using 'self amalgamating' wire as Burns themselves used to use ... which means less hassle potting then taping the coils
Anyway ... wound and potted, and with the first holding tapes manoeuvred into place with tweezers - a really horrible job! Less so now with the much firmer coils I now work with.

The air coil simply slides off the former... and once fully taped ...

Is reunited with the base-plate and magnets.

There are a whole lot of lessons that can be learned from old Burns pickups ... and even applied to modern seven and eight string units. Air coils obviously take up less space than conventional bobbin pickups and can be potted/amalgamated more easily and thoroughly and the centre mounted magnet is super direct with it's field giving very open and single coil like tones even when used in a humbucker as below ... A custom microtonal 7 string by Flame Guitars in the UK using a pair of my buckers

Anyway one Burns GB65 fixed and back to rocking ....
Next time perhaps crumbling Hagstrom pickups ....

 

[crushingpetal]

This is fucking cool.

 

[Concerto412]

Sooo cool. Thanks for another great write-up, and respect to the jig-work. I like seeing simple, practical solutions like that. The tape job on a soft air-coil such as that looks like it could be a nightmare otherwise!
That microtonal 7 looks wild - did you have anything to do with the segmented (?) single coil in the middle of that as well?

 

[Das Gitarrenwiesel]

Sooo cool. Thanks for another great write-up, and respect to the jig-work. I like seeing simple, practical solutions like that. The tape job on a soft air-coil such as that looks like it could be a nightmare otherwise!
That microtonal 7 looks wild - did you have anything to do with the segmented (?) single coil in the middle of that as well?

No I believe it was a pickup requested by the customer the guitar was built for ... but next time I talk to the guys at Flame Guitars I'll find out what it was. As a pickup maker I see a lot of other stuff used with your pickups ... I don't do active or MIDI pickups ....but that's great.

I have a cupboard full of jigs ... I kinda build them as I encounter a new pickup that gives me a problem. For example I have a jig that allows me to rewind Rickenbacker pickups in the correct direction while still having the non removable poles facing the back plate of my winding machine, I have a jig that allows me to rewind old Hofner pickups with the bobbin still riveted to the baseplate with the magnets in situ (replacing rivets is a pain). I have a very simple jig that allows me to rewind firebird bobbins and still use the winding machine's tailstock ... meaning I don't have to mess about with tape.
It's my living, but it's also huge fun

 

[Das Gitarrenwiesel]

Hagstrom guitars were super popular in Europe in the 60s ... and in fact in some countries like Finland ... which I count as my second home (as I've visited there so many times) they were pretty much all you could buy back in the day!
They are still great instruments, but the old Hagstrom pickups have one major achilles heel: they used bobbins cast out of some sort of epoxy, which with age crumbles to pieces ... this allows the unsupported coil wires to break ... and that's the end of that!

Below is the dead Hagsteom bass pickup ... about 1963 I think
And next to it is a chunk of 4mm black acrylic I cut after scanning the original bobbin top. Ypu can see I';ve already been working on shaping the end with a file ....

Acrylic can be shaped and polished pretty easily, and while I couldn't get the full 5mm depth of the original top 'flatwork', I got close enough not to be noticeable once fitted to the guitar.
Here's the top

Here we have that acrylic top flatwork with bottom flatwork added and alnico 5 magnets to complete a bobbin assembly.

You might ask yourself how I could work out how many wire turns to give the new reproduction pickup to equal the original ... well the first job was to determine the wire gauge used.
This is pretty simple ... no you can't just measure it with a micrometer or vernier gauge directly it's two small .... you need to take a foot or so of the old wire which you should be able to get off intact ... then wrap it tightly around a small screwdriver shaft ... exactly ten turns wound tight against each other. Then you measure those ten turns width with your vernier and divide by ten ... and hey presto your wire gauge.
But, you may say, that doesn't tell you how many turns the old bobbin had .... well there's a trick to that too. Simply weigh the old pickup, then cut off the scrap wire and weigh the bobbin assembly ... obviously the difference is the weight of copper wire wound. Then you keep a very exact digital scales by the winding machine, and being careful not to break the wire, you wind the new bobbin till the assembly weighs the same as the original. It's actually super accurate.

Before you ask .... I'd stripped the wire from one of these before and had the wire gauge and turn count in my notes

I think it's super important to keep these historical old instruments going and in playable condition ... something for future generations to appreciate.

More soon

 

[Das Gitarrenwiesel]

So coming up soon, we have gold foils, Gibson P13 (the pickup that gave birth to the P90) dead Shergold pickups from the good old 70s in the UK ... plus I invisibly mend a Seymour Duncan that someone put a drill bit through ... and make a ten string humbucker to replace someone's ten string single coil ...
All coming up soon