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Leif
19-09-2020, 02:57 PM
Hi guys,

Is it a stupid question to ask which to screw in first - the neck or the bridge? I have seen their videos wherein one it is bridge and another it is neck.

And at which point do you measure scale length? Near end of build right before neck attachment or first thing during mock build?

Cheers,

Leif.

fender3x
19-09-2020, 11:55 PM
It may make a difference what kind of guitar it is. In general, especially if there are no holes yet for the bridge, it will be easier to move around a bit.

No matter what else you do, dry fit neck pups and bridge to see if you can get everything to line up.

The high E saddle on the bridge should be the same distance from the center of the 12th fret as the center of the 12th fret is from the nut.

Sent from my ONEPLUS A3000 using Tapatalk

fender3x
20-09-2020, 12:20 AM
FWIW I just did an F-style, and decided to finish the neck and put in the tuners before doing any drilling. That way I could see how the E strings would go over the neck and pups.

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McCreed
20-09-2020, 07:10 AM
With an ST kit like you have, the final bridge position will be determined by measuring off of the nut, so the short answer is neck first, then bridge.

The longer answer is that you should clamp the neck in place before drilling the holes in the heel so you get it properly aligned, which will in turn affect the position of the bridge both laterally and longitudinally.

All you need for this process is a clamp (preferably with some small wood blocks) a steel rule at least 600mm long*, and a pencil.

*A longer rule will allow you measure scale length without splitting it half & half, but 600 will work just fine and is pleanty for marking out the neck alignment.

As for scale length, you're better off NOT doing the "12th fret x 2" method. Measure the entire scale length from the fretboard side of the nut to the break point of E1 saddle (treble E - adjusted forward). This process has been discussed here numerous times, in numerous threads. A forum search will find those for you.

Leif
20-09-2020, 11:56 AM
Thank you so much guys,

I appreciate it.
I have read about this in the threads (having the E1 saddle adjusted all the way forward at scale length). Wouldn't it be better to have the saddles adjusted to around 50 percent at point of scale length so you have room to move forwards and backwards?

Cheers

Simon Barden
21-09-2020, 02:15 AM
No. The way strings work, there is always a small piece at either end that isn't vibrating properly, so the intonated scale length will always be slightly longer than the nominal (2 x nut to crown of 12th fret distance) scale length. The thicket the string, the longer this length is (which is why the lower string saddles almost always sit further back than the top strings). I'd leave 2-3mm of possible forward travel available, but no more. Move the saddles back to 50% of intonation screw length and you'll find that the intonation springs get compressed completely on the lower strings. Even with the saddles set forwards, you may still find that the low E and A saddle springs may have to be cut down slightly to allow sufficient rear movement.

McCreed
21-09-2020, 06:52 AM
^^^^^^^^^
What SB said!

fender3x
21-09-2020, 11:36 AM
As for scale length, you're better off NOT doing the "12th fret x 2" method. Measure the entire scale length from the fretboard side of the nut to the break point of E1 saddle (treble E - adjusted forward).

Can you say a little more about why it's better to measure the entire scale length rather than the 12th x 2 method? Not doubting the wisdom of your advice, just not clear about the reason. On the build I just completed they would have been identical measures.

Simon Barden
21-09-2020, 04:37 PM
A guitar’s/bass’s scale length is defined by being twice the distance from the nut to the crown of the 12th fret. The nut to 12th fret distance is the only fixed value in the intonation equation. Even that needs to be done with the neck set straight.

Measuring the nominal scale length to decide bridge position is always best done as a single measurement with a stiff metal ruler to reduce accumulated errors. You may be able to measure to say ± 0.5mm accuracy, so two separate measurements will be within ± 1mm. Many rulers have quite thick line markings, so measuring to a higher accuracy is hard. Flexible steel tape measures really aren’t good for this sort of thing due to their bending and stretching. And dressmaking-style tape measures are just plain inaccurate. One I have is up to 2mm out over 100mm. So yes, always measure the scale length from the nut to the nominal length in one go.

After that, the intonated scale length is down to the vagaries of the string material, the amount of neck relief and the force which you use to press the strings down. Your ideal string has a uniform diameter and mass per unit length all along it. There will always be slight fluctuations in this, but the more uniform these values are along the length, the better. Bigger variations mean more variance between the nominal and intonated length. Once the strings start to oxidise in places, then the oxide will have a different mass to the base metal mass, so you get larger variations in mass per unit length along the string. The more neck relief you have the shorter the straight line distance is from the nut to the 12th fret. Not by very much at all, but it's there.

But its mainly the non-fully vibrating parts of the string that make the most difference to the active string length and the intonated saddle positions.

Easier to envisage if you go to extremes. An infinitely thin string will vibrate all the way along its length between the two end pivot points, so the intonated scale length will equal the nominal scale length. There is no string thickness/resistance to stop the string just beyond the pivot point from moving (say 0.1mm), so it behaves just like the drawings in physics textbooks.

But now imagine that the string is very thick, say 10mm. There is now resistance to movement in all the up/down/sideways directions and at the point just beyond the pivot point, there really isn't going to be much movement at all. Indeed, you need to make a 10mm 'string' very long indeed in order to get enough flexibility to get noticeable displacement from the resting position. There is a very long 'dead' length at the two neds where the string really just doesn't vibrate at all. Certainly with this 'string' at 0.1mm from a pivot point you'd need a huge force/string displacement too measure any movement at all.

So the thicker the string, the longer the dead length where the string isn't vibrating properly as it's transitioning from being held firm to vibrating freely.

It's not just thickness, but also the string material. Make that 10mm string from soft rubber instead of steel and there's far less resistance to sideways movement, and the dead length is much, much less. Which is why nylon string guitars have very nearly no slope on the bridge and both ends are set back by 1.5mm longer than the nominal scale length. Also, the added tension of fretting a nylon string is much less compared to steel strings.

Different 'steel' string materials have different mechanical stiffness, so some string makes/types will be slightly softer than others for the same string diameter. For an example you've can get plain steel, nickel coated steel and stainless steel plain strings. Within those, you'll get slightly different carbon contents and other impurities, which will all affect stiffness, mass/unit length and the tension required to get them to pitch.

Notice how a wound 4th saddle is normally set further forward than a solid 3rd string saddle? That's because the tension and vibration length is mainly set by the inner core wire, which is a lot thinner than a plain 3rd. The windings are there to increase the mass per unit length in order to get a low enough note. Using solid strings for the 4th, 5th and 6 strings would result in very long string dead lengths, and you'd need very staggered bridges indeed, and probably sloped frets to get the guitar in tune. They'd also be very stiff indeed to play.

String windings need to grip on to the central core securely. If the wraps become loose in places, the windings can stretch out and bunch up, resulting in unequal mass/unit length and intonation issues with some frets sounding really off compared to others. Any 12-note/octave tuning system is a compromise of some sorts, there is no perfect tuning system, but strings of uneven thickness and/or consistency make this even worse.

Fretting pressure can also noticeably raise and lower a strings pitch. The taller your frets, the more the variation in fretting pressure that can be applied. Once the strings are on the board they can't stretch any more through downward pressure. If you set your 12th fret intonation just lightly holding the string down to the fret, but in proper playing you press down much harder, then the upper fret notes will sound sharp when you play.

And this then connects to your action and overall set-up. With a low action, you are stretching the string less when you fret it than if you have a high action. And stretching the string results in an increase in string tension, which will raise the pitch and make the note sharp. Some of this is incorporated into the fret positioning, but generally, the higher the action, the further back the saddles have to go to get the intonation correct.

And as the strings age and stretch unevenly and oxidise unevenly, then they really need small intonation adjustments, And any time you change the strings, you should really check the intonation; definitely when changing brands or string material or string gauge.

Any intonation setting ends up a slight compromise, but that doesn't mean you can't try and get it as close as you can.

Ricky
23-09-2020, 05:34 AM
Well said Simon.
Best complete explanation I have seen.

This should be a 'Sticky' somewhere.

Cheers
Ricky