With the embarrasing foul up with my wiring schematic now rectified, (we all learn by making mistakes), the Ash Stratocaster is ready to string and setup. As usual, I start with a few modifications to the nut. The Fender neck comes with the usual, “synthetic bone” composite nut – wheras I prefer the sound of a bone nut. The 7.25″ neck radius leads me to believe I’ll need a curved bone blank – and that’s borne out when I tap the original nut out of its’ slot with a fine drift. The Fender nut slot is curved – but only just.
I have a small stock of HOSCO bone nut blanks – and they always seem to be a little bit more curved on the bottom, and a little bit wider than the standard Fender blanks. I use an old profile gauge to trace the shape of the bottom of the nut slot, and you can see how that compares with the supplied Fender nut, and the HOSCO replacement I intend to use. Even the Fender nut doesn’t appear to fully match the slot profile. I’m pretty sure I can reshape the new nut to fit better. Bone nuts always sound superior, in my opinion, and I’d hope to get a better transfer of tone with a better fitting nut as well.
After a bit of work with some 240 grit, I manage to reshape the foot of the new nut, and by temporarily taping the nut to a piece of thin MDF, I manage to reduce the overall width of the nut evenly, by rubbing it flat on the grit paper. I check the fit often, and once I get close, I up the grit to 340 and start to fine-tune the shape. Eventually I manage to get the nut to fit the slot, and stay firmly in place without the need for anything to secure it. The ends of the nut protrude from the edges of the neck slightly, so the nut is gently reshaped at the ends – until the nut fits perfectly.
The nut slots still need to be propely filed, and opened up to fit my chosen string set – but first I need to look at the other end of the guitar. Normally – I’d slot the nut early on in the setup – but since the tremolo geometry will be changed – due to the fact I’m unblocking it, and letting it float – I want to set the approximate height of the tremolo plate first, before I begin to look at neck relief, string heights and nut height.
With the new nut installed, I string the guitar in the usual manner. Since the tremolo is now unblocked – the moment I begin to stretch the strings, the tremolo plate begins to rise with the increased string tension. Normally the springs in the back chamber work against this – so the ideal point of balance between the springs and strings is the target I’m aiming for. Of course – the more you stretch the strings into tune – the more they pull, and the more force you need from the springs, to keep the system at the balance point. Finding the balance point with three variables is therefore difficult to achieve by increments.
Things are further complicated when you consider that the tremolo is supposed to operate in two directions – to both raise and lower the note produced by the strings. This means that the plate needs to be capable of moving both up and down at the heel. The ideal balance point is therefore achieved with the heel of the tremolo plate held a few millimetres above the body of the guitar. This enables the player to pull back on the whammy bar to stretch the strings and raise the pitch – and also press the bar, and lower the pitch.
So to locate this perfect balance point, I install all of the three springs, and screw the claw fully in to the body – to provide some resistive force against the strings. I then stretch the strings towards proper tune – although it’s an almost impossible job since the intonation is a bit out, and the tremolo tension is still not yet balanced. Basically, I’m looking for a point of balance where the heel of the tremolo plate is held at a certain point above the body – and I’m looking for that point of balance to be just enough to enable me to push the plate back and get a full tone raise in pitch when I do so.
To keep the tremolo plate, and the block in exactly the right place, I fashion a plug out of a few coins and a bit of masking tape. When the plate is in the right place, the gap between the block and the back of the rout measures roughly, to approximately one Pound coin, with a 5p coin on top. A few wraps of masking tape keeps the two coins together, and slightly increases the size of the plug until it just fits into the gap. Then – with the coin plugin place, I can screw the spring claw out slightly. This means that the strings are now pulling relatively harder, and this pulls the block back against the plug, and the back of the rout. Most importantly – it means the tremolo is temporarily blocked in the ideal position. I can now concentrate on getting the strings to the correct tension, and in tune.
Just to make sure there isn’t a point when the springs might “win” in terms of tension – Fender recommend you remove one of the springs temporarily, so that the tension of the strings is always going to keep that blocked tremolo in the perfect position. The strings are each stretched out a little, with upward pulls – and are brought to concert pitch using a chromatic tuner. The intonation is still well out – but setting the strings to the correct pitch by tuner means the exact pressure exerted by the strings in tune, is now pulling on the tremolo plate. All I need to do – is to match that exact level of pressure on the spring side, and the tremolo should stay balanced at the ideal position.
The claw is slackened off enough so that the third spring can be replaced, and then the claw is gradually screwed into the body – by turning each of the screws in turn – keeping the plate level with the top of the chamber. Eventually, the springs pull just enough to release the temporary block, and the coin plug can be pulled out. The spring claw position is then fine tuned so that the tuning of the strings is restored back to concert pitch, as checked by the tuner. A quick check of the tremolo plate shows it’s holding at the balance point. The tremolo is floating.
But although the tremolo is floating and functional – the guitar is still far from a proper setup. The new neck obviously has a slightly different geometry than the old one. Who knows – it may even have a different overall length. I need to go through all of the basic setup checks again.
Firstly – with a capo on the first fret, I finger each of the outside “E” strings and check the string to fret height at the eighth fret. For a 7.25″ radius neck, Fender recommend a clearance of 0.012″ at this point, and it’s reassuring to find that the neck is bang on tolerance – fresh from the box and without the need for any further adjustment with the truss rod. Normally, I’d move on to slotting the nut from here – but since the guitar has been previously setup, and since the tremolo relationship has changed, I first want to check things out there.
I set the saddle height of the bass “E” string – by adjusting the saddle grub screws, until there’s a 5/64″ inch (2.0mm) clearance at the 17th fret. The treble “E” string is then adjusted until there’s a 4/64″ clearance (1.6mm). Then, using a radius gauge – I set the saddle heights for all of the other strings until their relative curvature matches the 7.25″ radius of the fingerboard. It’s likely this will need some further fine tuning later – but it puts things into a more realistic state, so I can move on and slot the nut. Meanwhile – it’s pleasing to see that the strings already fall into quite a playable position. Also – the flat parts of each string saddle are adjusted to lie parallel with the top face of the body. There are a lot of tone nerds out there who seem to think that this is the best arrangement for getting the best tone, but I think it might also help the stability of the individual saddles.
A previous check of the frets on the neck had shown them to be level and consistent. That’s what I’d expect from Fender. Quality and consistency straight out of the box. The fret height at the nut measured out to be 0.033″ across the neck – so the bottom of each nut slot was calculated using this figure, in addition to the desired string heights. This provides the ideal clearance dimensions at the first fret. I’m aiming for 0.020″ at the bass side, and 0.012 at the treble. If I assign 0.020″ for the “E” and “A” strings, and 0.012″ for the “B” and “E” strings – then the “D” and “G” strings will sit halfway in-between, at 0.016″. Adding the fret height to these figures gives the measurements from the fingerboard to the bottom of each nut slot – running from bass to treble they are:
E 0.053″, A – 0.053″, D – 0.049″, G – 0.049″, B – 0.045″, E – 0.045″.
I cut each slot to the required depth using a sized nut slotting file, and some stacked feeler gauges as a file stop. I make sure each slot curves away and down at the headstock side. This keeps string contact to a minimum, and stops any buzzing from the strings. Once the slots have been filed, I add half a string’s diameter to each of the nut slot dimensions, and mark a point on the nut at each string location. This marks the optimal overall height of the nut, so that the strings will sit correctly in their slots. The nut can now be gently tapped out, and filed down to the required height. Once the nut has been shaped, it’s given a quick polish up with fine grit paper, and each slot is cleaned out before being lubricated with fret lube. The nut is replaced, and seated properly. The guitar is once again brought back to tune, and each string is checked to make sure the ideal string height over the first fret has been achieved. By fretting each string at the third fret, the string between the third fret and the nut should just about clear the first fret. Everything checks out OK, and there is no apparent buzzing of any string in the lower fret positions.
In fact – the whole neck seems playable. The overall string heights are checked, and there’s enough adjustment to reduce the string heights to below Fender recommendations. With the strings already just about there – I can drop each grub screw by a quarter turn or so, and get an even lower action. It’s noticeable that the action is low at the nut, but a little higher than I’d like further up the neck. I had originally used a neck shim on this guitar, and I’m starting to wonder whether the neck pocket rout might be a little out somewhere. I still have a spare StewMac, 0.05″ shim from before – so I detune the strings once again, and slip the shim in to see how that changes the geometry.
That seems to make a big difference, and the guitar is much easier to play. I think the neck pocket might be slightly too deep. The shim seems to tighten everything up, and the action is good all the way up the neck. I spend a bit of time setting each string to get the best playability out of the guitar. It’s becoming apparent that this neck is so much better than the original, non-Fender neck I had installed. So much more comfortable to play, and things don’t start to choke – even bending strings on the radiused fingerboard.
But, of course – taking the strings off has lost my balance reference point. I have to go through the same process to balance the tremolo before I can really begin to fine tune things again. Normally, having set the tremolo balance point, it’s important not to change the tuning of any string during the setup process – since that upsets the whole system. There’s a bit of work to be done to find that exact balance point again – but once the balance point is found – by stopping the tremolo with the temporary stop, I can fine tune the setup, and make sure the intonation is good across the whole neck. With the string heights and action now just about perfect for me, I check the intonation of each string, and set each so that each string is in tune with itself – open and at the twelfth fret harmonic.
It’s a pain to have to run through the whole setup process again, but there’s a logic to the approach of floating the tremolo which makes perfect sense. You just have to get out of the habit of automatically reaching for the tuners each time you need to micro adjust something in the setup, and if you do have to change things – there’s no alternative but to go through the process of stopping the tremolo temporarily, to re-discover the perfect balance point. It’s a bit drawn out – but doing things this way has already given me a much more satisfactory result than with any other attempts I’ve had, in getting to grips with the Stratocaster tremolo.
I’m sure there will still be bits to fine tune, as the strings and springs settle in – but there’s a definite, immediate improvement to the guitars’ action and playability. Now I can really check out the pickups.
I fit the tremolo arm – having swapped it’s tip for one in the Vintage 60’s set, and then set the pickup heights to reflect the standard Fender Vintage specification of 6/64″ (2.4mm) on the bass side and 5/64″ (2.0mm) on the treble. The difference between the old pickups and the upgrades is astonishing. The Custom Shop ’69’s are the absolute definitive Stratocaster sounds I’ve been looking for. The Seymour Duncan, Custom Shop SSL-5 is massively hotter than a standard bridge, and so I back it off a bit with the height adjusterss, to balance the output across the pickups better. But it sounds amazing, and you can hear those classic Strat tones, right off the bat. The tone mod is useful in blending the characteristics of the Fender pickups with the Seymour Duncan across all of the selections, although it sometimes seems to duplicate a kind of neck tone on the middle pickup. I’ll see how it fits and make a judgement later – but for now, this guitar promises to be an absolute blast. And I have a tremolo to use as well! All of the mods seem to live up to their promise, and it’s certainly an overall dramatic upgrade to the guitar. Sometimes, it just pays to buy original quality parts.
There’s still some fine tuning to do, and I’m sure I’ll be tweaking the pickup heights for ages, as I get used to the new hardware through my amp and pedals – but the guitar is just so much more playable – it’ll be a joy. Feels like a whole new guitar. I was happy with what I originally learned in building the original – but upgrading has been so worthwhile in improving on that original. And importantly, it’s been a valuable lesson in knowing what upgrades can do to correct or change particular characteristics of an instrument. Highly recommended.