Fender “57” Precision Bass. Rebuild and upgrade.

Both the body, and the neck of the MIJ Precision have been cleaned and polished, and are ready to be joined again. All of the stripped out screws are going to be replaced with stainless steel replacements. Complete stainless steel screw sets for the Precision are hard to find – but I was fortunate to come across a set, put together by another builder who had gone through the process of sourcing replacement screws for his project. I’ve already used the stainless replacement screws to re-fit the tuners to the headstock – now the four neck bolts are used to join the neck and body. The original chrome plate is cleaned, polished and re-used – despite showing a few belt scratches.


With the body and neck joined – I can now check the fit of the gold coloured, anodized aluminium pickguard. The single ply, aluminum plate was introduced with the ’57 re-design of the original Precision, although it was soon to be permanently replaced in favour of the, (cheaper?), plastic alternatives seen to the present day. Original plates are rare – but Fender still produce a few metal plates for retro-fitting, in the old style. Presumably for people like me who want to return their guitars to a state which fully reflects their original design heritage. That said – the retro plates are hard to find here, in the UK. In fact is isn’t only the gold scratchplate which has to be sourced from abroad. The ashtray and pickup covers, as well as the Luxe capacitor, are all sourced from suppliers in Germany.


The pickguard is virtually a straight swap – but the neck pocket cut out is too tight. In fact, the lower side of the cutout bites in tightly to the wood of the neck. I could force it on – but there would inevitably be some damage to the wood, and any subsequent removal of the neck would be impossible without the prior removal of the scratchplate. Nothing for it – I’ll have to try and reshape the plate.

I’m well used to shaving bits off plastic pickguards to provide a perfect fit – but the millimetre or so thick aluminium plate is a slightly more daunting prospect. Not least because the plate costs upwards of £55.00. With a gold finish which easily scratches off leaving shiny aluminium beneath, and with the only tool suitable to do the job being a small, curved, diamond file – it takes a lot of to-ing and fro-ing, measuring and test-fitting, to gradually reshape the neck cutout so that the plate sits correctly. I reckon a whole millimetre has to come off the side, with a consequential reshaping of the curve needed to correct the fit at the heel.

I try to angle the file blade so that the scraped edge of the plate is angled downwards towards the body, and I try not to leave any burr metal on the face – which might scratch the body or neck, and give away a poor DIY job. Despite all the extra care – I still manage to take a small nick out of the neck on one test fit. The small notch is filled with coloured restoration wax, and polished out the best I can manage.


Eventually – the neck sits correctly, and I can’t see any evidence of the reshaping when the plate is in position. I double check the fit, and ensure that the pickups will fit correctly – confirming also that the CTS pots won’t foul on the sides of the control rout when fitted to the plate. It all looks fine, although most of the screw holes appear to be a few millimetres out. In fact – only one is in exactly the correct position. The new, (old-style), plate is a 10-hole version, wheras more modern, plastic plates tend to have 13 screws. Because of this – I don’t have to relocate all of the holes, so I mark the ones I need to attend to with small pieces of masking tape.

The marked holes are then filled with small lengths of pointed softwood dowel – glued in with white, PVA wood glue. All pre-cut so that the ends sit just below the surface level of the body. I don’t want to leave any glue on the surface, or run the risk of scratching the body whilst trimming back any over-long wood plugs. Once the glue has dried overnight, I re-fit the plate and mark the new centres for all of the required holes with a bradawl. The screwholes are then re-drilled with a sharp wood bit – turning the bit anti-clockwise at first, to avoid splitting the finish. Stainless steel replacement screws are tapped into each of the new holes, and the plate is fully test fitted, before it’s removed again and replaced in it’s original packaging for protection.


The spilt coil design of the Precision pickups effectively means that the output signal already benefits from hum-cancelling. Even so – I always like to copper shield my guitars from any unwanted, external electrical interference. This seems even more important in domestic surroundings. The pickup, and main control cavities are lined with thick copper foil, which has a conductive, self-adhesive backing. I run plenty of foil up and over the edges of the openings so that the foil has an opportunity to complete a cage effect, using the conductive scratchplate as part of the ground side of the circuit. To achieve continuity between the two compartments – I run a length of foil between the two, over the face of the body. No need to run a connecting wire in this case. Continuity can be achieved with just this bridging piece of foil.

The original bridge grounding wire was cut short – with only the very end of the wire touching the underside of the bridge. I run a piece of black, cloth covered wire through the conduit from the main cavity – leaving quite a long tail at either end. I then strip back all of the covering at the bridge side, and run the bare wire in a slight loop across the footprint of the bridge plate, and down one of the screw holes. That will ensure the wire stays in place, and that there’s a good, conductive, metal to metal contact at all times.

In the control cut-out, I locate a suitable point for a central grounding point, and drive a small screw into the side wall of the cavity, where it won’t run foul of any of the pots. I trim the bridge ground wire to the correct length, and then strip enough bare wire so that I can poke the end into the hole created by the grounding screw, and also leave a bare length – about a centimetre – exposed in the control chamber. The screw holds the wire in place, but a blob of solder is also laid so that the bare part of the wire is held firmly in place, with a good conductive connection – just to the side of the screw. The screw will allow me to attach a small lug, which will connect the other ground wires from the jack socket, and the backs of the pots to the central, common, ground.


With the ground side of the circuit mostly laid, the replacement bridge can be screwed into place using the stainless steel replacement screws. The new bridge is a Fender, Custom Shop, Vintage style bridge. It’s a heavy chromed bridge plate, with turned nickel saddles – as opposed to the smooth, (poorly) chromed saddles supplied on the MIJ version. The Custom Shop plate doesn’t look much different apart from the saddles – although the overall chrome job does, perhaps,  look a little bit better generally. To stop the saddle grub screws from needlessly scratching the shiny new chrome job, I leave the protective card in place, for now.


Before the scratchplate is screwed into place again, I need to complete the wiring job on the reverse. Two 250k, vintage taper, CTS pots are paired with a mono, Switchcraft jack socket – with some black and white, cloth covered wire to complete the job. As usual, a little shrink tubing comes in handy to ensure certain solder joints stay insulated, and to prevent things coming astray. I’ll be replacing the original, green “chiclet” style capacitor with a 1957 replica “Red Dime” capacitor, by Luxe. The 0.1mf “Red Dime” was used on Stratocaster and Precision models between 1961 and 1968, (wheras you might, more regularly see at 0.04mf or even 0.02mf examples in there, these days). The increased capacitance produces a different characteristic when incorporated into the tone circuit. More of the treble signal is taken away as the tone is rolled off – resulting in quite a marked muffling of the sound – with most of the tops, and a good deal of mid-range taken away. This is somewhat reminiscent of the effects that “Dark Circuit” wirings gave to the Fender sound during the period, and should work well with the ’62 styled pickups to provide that late 1950’s / early 1960’s  sound pallette. Although the guitar’s looks will be rooted in the stylings provided by the 1957 redesign – its’ sonic signature will draw more from the 1962 period.


The Precision circuit is, perhaps, just about the simplest guitar wiring circuit there is. That said – there appear to be a number of ways of achieving the same result – depending on where you ground the circuit, and how you incorporate the capacitor. Since my circuit has the additional, central grounding point to take into account – my own solution will be a bit of a hybrid, with elements from both the traditional circuit, and more modern versions.


I choose to lay the capacitor under the tone pot – as was the norm on the older, vintage Fender wiring schematics – but I’ll run my ground from the back of the tone pot to share a lug with the ground wire from the jack socket. This single lug can then be attached to the central grounding point, and secured with the small screw, once the plate is fitted into position. This actually leaves the volume pot, essentially, ungrounded – and I’m undecided whether to add a grounding jumper between the two pots. In the end, I decide to leave the volume pot ungrounded. Since many of the vintage schematics show the pots as ungrounded, it’s probably an illustration of just how unnesessary it is to fully shield and ground a split coil setup like the Precision. (It’s maybe even possible that the pots earth themslves when connected to the aluminium scratchplate). If there ever should be any troublesome earth hum detected in the future – it’ll be the very first modification I make to the circuit.

With the circuit complete, and pretty much self-contained – all I need to do before screwing the plate down, is to attach the pickup leads, and make the central ground connection.


The new Custom ’62 pickups are test-fitted to ensure they move freely, in and out within the scratchplate cut-outs, once they’re screwed into place. I have a set of replacement screws for the pickups – but I’m forced to use the supplied screws once I discover that the stainless screw heads are, crucially, a millimetre or so larger than they need to be. This means the pickup covers won’t quite fit with the new screws in place, and so the chromed, Fender supplied screws have to be used instead. Fortunately, the pickup position matches the originally drilled screw holes in the cavity perfectly, and once the pickups are screwed down into position, the scratchplate fits over – allowing proper movement up and down, once the pickup screws are adjusted.

With all the components for the circuit now in place, the ground lug can be attached to the central grounding point, and the two pickup leads permanently soldered into the circuit at the pots. The usual checks with the bass connected to an amplifier, and a screwdriver tapped to the pickups, confirms the circuit is correctly wired and that all components are working as they should. The circuit is silent – with no earth hum. The scratchplate screws are then screwed down into place.


The pickguard plate comes pre-drilled for the pickup “ashtray” cover and for a “thumb-rest”. Somewhat bizarrely, the early “thumb” rests were installed below the strings, (exactly where your thumb isn’t). Later models have the thumb-rest above the strings, and the template provided with the genuine, Fender, thumb rest does, indeed, show the placement as above the strings. However – there are more than enough archive photos to confirm the 1957 placement of the rest, as corresponding to the pre-drilled holes in the pickguard below the strings. Myself – I tend to use the low “E” string as a kind of resting point for my thumb – since it also allows me to mute the low strings when playing with my fingers. The “thumb” rest placed under the strings becomes a bit more of a middle, or third finger rest for me.

The stainless steel replacement screw set doesn’t, unfortunately, come with replacements for the, (cosmetic), add-ons – so Fender supplied screws will have to be used. There aren’t any screws supplied with the pick up cover however, but I’m able to use two spare screws, originally supplied to fit the bridge, to hold the cover in place. All four screw holes  for the pickup cover and thumb-rest are already pre-drilled in the scratchplate – so that takes care of the locations. All I have to do is drill out the holes, and then let the screws tap in using a little wax as lubricant.


There’s little to do, to help set up the bass at this stage – but I can, reasonably closely, reproduce the existing bridge saddle positions based on the old bridge. I can also, similarly, set the pickup and string heights to approximate settings. To change the pickup heights, I need the pickup cover off, and there’s little point in even fitting the bridge cover until I’ve got the setup done – so both of the chrome covers are returned to their packaging, and kept on one side.


I’ve used Elites bass strings for as long as I can remember, and originally came across them when I was a regular visitor to the Bass Centre in Wapping – where Elites were the “in-house” strings. I think I’ve only ever used their “Stadium” series, stainless steel strings before. They have a characteristic, bright, almost piano-like, sound when they’re brand new, and they dull with use to provide a good, typical bass sound. Quite often, I’d leave the same set on for years. I suppose I did get frustrated sometimes – in studios and with live work – when the bass sound would, more often than not, be pushed into a generic sort of envelope where any individual characteristics were squashed out. All in order to provide a flat, generic response. (“It’s just a bass – let me DI it straight through the desk”). So much for all the little adjustments in tone, at rehearsals over the years. I think I just settled into the mindset that different strings weren’t ultimately going to make that much difference.

There’s a particular early Fender Precision sound which is percussive, yet has a deep bass element. There’s a growl there too when the amp is driven slightly. I’m looking for that exact sound in upgrading this P57, and I’m going to try flatwound strings for the first time, in order to try and maximise those particular characteristics. The “Stadium” series strings are great for picking up the percussive taps and finger sounds created in play – but I’m hoping the flatwounds will concentrate more on frequency driven elements of the tone. Rather than on brighter, percussive qualities.

So a set of Elites “Detroit Flats”, (45 to 105 top), are stretched out and fitted to the bass. It’s pleasing to see that the bass settles back into tune again, and stays there. That neck action is definitely too high though. Checking the action with a feeler gaugue is pointless. I’m looking at roughly 3.0mm, when it should be more like 0.35mm, (0.014″), for this 7.25″ radius neck. That means the neck has to come off again, and the truss rod tightened by a quarter turn. With the neck re-installed, and the bass returned to tune, the action is still way too much, so the neck is off again, and the truss rod screw given another quarter turn.

This time, the neck settles to show an action just under the standard, Fender recommended specification – but I don’t play too heavy, and prefer a melodic finger style. I figure it’ll do for now. String heights are set at the bridge to the standard, 7/64″ (2.8mm) at the bass , “E” side, and 6/64, (2.4mm) at the treble “G” side. The two centre strings are set using a curve gauge so that they follow the curve of the fingerboard. A final intonation check reveals a couple of tweaks required to correct slight discrepancies in my approximate bridge settings. A quick test, and I’m happy with the setup. The action is nice and light, and – even acoustically – it’s a real novelty to hear the vast reduction in left hand noise from the strings at the frets.

Pickup heights are set to the recommended, 8/64″ (3.2mm) at the bass side, and 6/64″ (2.4mm) at the treble, with each pickup element slightly angled so that the poles follow the curve of the strings. The bass is then amplified, and minor pickup height adjustments made to equalise the string sounds as much as possible. I try to adjust things so that identical notes on different strings sound as similar as possible. I also check the magnet poles aren’t “grabbing” at the strings too much. Any pulsing or “strobing” of a sustained note, gives the game away.


With the bass now properly setup – all I need to do is fix the bridge cover in place. I use the edges of the bridge plate and a set square to accurately position some masking tape around the bridge plate – checking that the sides remain in line with the strings, and perpendicular to the base. The cover can then be positioned – checking that it’s centred, and square to the bottom of the guitar. The mounting hole positions are double-checked by measuring exact the distance from the pickup cover mounting screws. Eventually – once everything looks right, and measures right – the two holes are marked and drilled.

I’m using another two of the spare, Fender bridge screws to attach the cover, and once the tape has been removed, the screws are tightened down to firmly anchor the cover. With the pickup cover in place – the upgrade is complete.


The visual change to the bass is marked. Wheras I always thought the two colour sunburst finish looked a bit “green” and lifeless with the old, white pickguard in place – the gold anodized plate gives an entirely different feel. When you think about it – Fender used some pretty gaudy materials, back in the day. Red plastic pearloid, chrome and anodized metal can all be quite reminiscent of cheap, fairground-type finishes, and I admit – I did wonder about that gold anodized plate at first. Last time I saw that sort of finish was on a cheap dining chair, in a lower-league football social club.

But the plate actually gives a whole new warmth to the visual finish. In direct light, it shines with a distinct bright yellow. In shadow, it accentuates the honey and amber tones in the neck and body. The overall effect is as if the entire guitar has been dipped in amber. The neck looks older, and the body glows – wheras the two colour sunburst had previously looked flat. Visually, the bass looks every inch a ’57. Sure, there are subtle differences in detail, and the neck clearly displays it’s 1996, Japanese origins – but the chrome ashtrays and amber hue just evoke the late 50’s original Precision basses, perfectly.


Sonically, the ’62 pickups are everything I hoped them to be. If there’s a case of hearing a particular sound, and then buying the pickups, “off the shelf”, in order to reproduce that exact character – then this is it. The ’62’s are Fender through and through. The bass sounds just like a Precision should. My little all-tube bass amp can manipulate the tone to create the typical sounds, right out of the box – and a quick test with my SansAmp Bass Driver provides a whole extra pallette available, should I ever wish to explore the possibilities of extra drive, presence or sub-bass. My favourite Bass might just still, probably, be my 1993, G&L LB-100 – but that’s likely to be kept in it’s case, in favour of this “new” Fender Precision, for a little while yet. My Precision now feels and sounds like the real deal.

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