Getting ready for the electronics. Polish, Superglue and Copper foil.

I’ve been reading up as much as I can about the Jaguar electronics circuitry – and it looks like a complicated business for a novice, like myself. Not just in terms of wiring – but also in terms of fitting it. There are several points where wires pass laterally between chambers via little routed holes. This is to provide continuity between all the ground side elements, and to connect up all of the various switches which are located in separate, isolated compartments. The original 1962 design for the Jaguar specified thin, brass plates to sit at the base of each of the separate chambers. These were linked together with soldered wires running between, and help to provide a continuous ground. With the Stratocaster I built recently, I used copper foil to line the chambers. Since there’s also a benefit using foil, (in that it helps shield the circuitry from unwanted interference), I’m going to use a belt and braces approach and take a leaf from both approaches. I’m not entirely sure if they will end up being compatible – but I’m following a logic. If I’m wrong – I’ll have to fix it, and I’ll have learned along the way.

So, I intend to line the cavities with self-adhesive copper foil. In which case, I need to be finished with polishing the body. I recently got hold of a second-hand car polisher on a well known auction site. I don’t have a car – but it was an absolute steal – and I thought it might add a bit of elbow grease to fine polishing. I’m still a little concerned that the places where I’ve drilled through the paint work might be a bit flaky – so I want to make sure everything is as secure as possible before I put the polisher anywhere near the body.

Nothing for it. I’ll have to strip the guitar down again. With all the plates off, and with the tremolo and neck off as well – I have one more chance to make sure it’s all in order. The neck plate hasn’t bitten into the paint work as I feared it might – so that’s good. However, a couple of the countersinks for the small screws around the scratchplate, have flaked off a bit. Nothing which will show with the plates on, however – but I’m not sure what will happen with a bit of extra friction from the polisher. A little super glue around the rim of each of the holes worked with the tremolo screw holes, and will help again here to secure the paint edges, and also seal the exposed wood to stop unwanted ingress of moisture. With the body carefully covered, exposing only the necessary areas – like some kind of patient in surgery, I go over each of the screw holes in turn. The glue goes off quite quickly, and I make sure each of the screw threads is left clear by running a waxed screw into each, before removing again.

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The picture above, (taken after the copper foil was applied), shows how each of the holes now has a little protective coating around the rim. I’m hoping that should be enough.

Then it’s time to test out the polisher. With the applicator bonnet on, it only takes a very small amount of polish to be able to cover each side in turn. From what I can gather from the instructions – only a tablespoon will do a whole car, so I’m using a small squeeze for each side. The polish is Meguiar’s Carnauba Wax – as before – and the applicator bonnet makes short work of covering each side. I can also do most of the edge – but there are a couple of stretches – especially round the horns at the neck end – where the head is too big. I’ll still have to do these areas by hand. Once the polish has been worked into the surface with the applicator, I change to the polishing bonnet, and go over the whole guitar body – keeping the head moving at all times, and double checking that the screw holes remain as they are. It only takes a few minutes and the body has a mirror polish better than the one I’d previously managed by hand.

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The body has a deep, liquid gloss – which is just what I’m looking for. Really close inspection shows a few, small scratches where I’ve obviously missed a polishing step somewhere – but they’re very hard to spot and, since scratches to the body are going to be inevitable with use, they help prevent me from getting too precious about the finish.

Then, it’s a quick check over the cavities – to make sure they’re clean and dust free. With the channels all clear, a layer of self-adhesive copper foil is applied, with a small area lapped over the edges onto the guitar face. Where the metal plates are located, I’ve kept the coverage to within the margins of each plate. Around the pickup channels, I’ve left it to about 5mm all around.

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The metal plates should complete a Farraday cage effect where they sit over the copper lined recesses. Where the pickup channels run under the pickguard – there is no conductive “top” to the cage, and so I put a square of copper foil on the back of the pickguard to complete the shielding there.

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The adhesive on the copper foil is conductive, and the foil I use is nice and thick – so where layers of foil overlap, there is good conductivity. This can be tested wherever copper touches copper with a multi-meter. Tests show the covered areas to be fully conductive and continuous, wherever the copper is contiguous. The small pickup switch rout remains isolated – but that should be rectified when I fit the conductive brass plates at the bottom of each chamber. Like I say – belt and braces.

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