Confused about scale length (baritone)

**Ronafett** · 31-10-2021, 10:53 AM

Hi, I’m starting on my JZ6 baritone kit (1st build) and am checking the scale length.
It measures 380mm to the 12th fret, but is more than 760mm to the bridge with the bridge saddles wound as forward as possible.
Is this going to cause problems?
I’ve watched the vid on the subject, but am still a bit befuddled by it all
Cheers
Ron

**McCreed** · 31-10-2021, 12:18 PM

Hi Ronaffet.

A couple of things... one, the overall scale length is the measurement to go by, not the 1/2 x 2.

30" is 762mm, and it looks to me like the E6 (treble E) saddle may be bloody near bang on to that. The E6 saddle is going to be the one that is always closest to the nut, so this is your determining factor. The E1 (bass E) will most always be the the furthest away from the nut.

IME, the bass E can be as much as 4mm further back than the treble E. This is why the bridge is angled the way it is. To compensate for that difference in distance. Your E1 saddle looks to be roughly 766mm at its furthest forward position. If you find it needs to be less than 766mm in order to intonate, you can remove the saddle and turn it around to loose another 2mm or so.

Whilst it is generally optimal to have a bit of forward adjustment to the E6, it may very well be fine where it is. Sometimes the treble E may intonate 1-1.5mm longer than the "exact" scale length. Every guitar is different.

Also, for more accurate measuring, a steel rule will give you a much better and consistent result. A tape measure can have a bit of play in the cleat on the end and give a different measurement depending of whether pulling or pushing the tape. (they can be calibrated and fixed, but that's another thread...)

**Ronafett** · 31-10-2021, 12:33 PM

Thanks so much for the reply, sorry the tape measure pics are a bit rough as it kept falling when I went to take the pic.
Sadly I only have a 300mm steel ruler, but might go looking for a longer one tomorrow.
Feeling a lot better about it now you've cleared up a few things and can get into the sanding, sanding, sanding
Thanks again

**robsmith** · 31-10-2021, 05:38 PM

A slightly off-topic question for Ron.
I'm waiting for my JZ6 to navigate it's way half way round the world, but am thinking about putting a piezo bridge pickup on, but need to know what the E-E string spacing is on the bridge so I check if the pickup in my "interesting box of bits" will fit or I will have to find (buy) another one. Could you please measure that on your standard one please.

(Note to self - I must buy a 1m rule next time I'm shopping in a hardware store, it's a grade one pain trying to use a 300mm rule to check neck lenghts...)

**Simon Barden** · 31-10-2021, 05:57 PM

Originally Posted by McCreed

A couple of things... one, the overall scale length is the measurement to go by, not the 1/2 x 2.

Technically no. The scale length is defined as twice the distance from the nut to the centre of the 12th fret. You can't get away from that. But the final intonated string length will be longer than the scale length, (which is what I think McCreed was trying to say), so the saddles will always be set back a bit from the nominal scale length. The thicker the string (or central core of the string for wound stings), the longer the intonated length will be.

On a standard scale guitar, the high E string will normally be set back by 0.5-1mm from the nominal scale length, depending on the chosen string gauge and the action height (higher action = greater intonated length). On a 30" scale guitar with a heavier gauge string choice, the intonated length for the top string will be a minimum of 1-2mm longer than the nominal scale length, probably nearer the 2mm mark.

As McCreed says, a tape measure isn't the most accurate way of measuring a distance (great for measuring between two points and transferring that length to say a piece of wood for cutting) and a steel or aluminium rule is best for measuring absolute distance in a situation like this. Fingerboard side of the nut top E slot to top E saddle slot.

I'd be the first to admit that the kits aren't the most accurately engineered kits in the world (made using cutting and routing jigs, not by CNC machines), and the factories can make errors in the post hole locations. But here I think you will be OK. I haven't seen anyone complaining about intonation issues before on this model, and fundamental problems do normally repeat themselves on kit types.

One other thing that can affect the overall nut to bridge length is the fit of the neck in the pocket. If they don't match up very well, then the neck can be pushed away by 1 mm or so from the body, moving the bridge position further away from the nut. Also check the pocket for small splinters or lumps in the wood that stop the neck seating fully. The end of the neck can normally be sanded to get a better fit into the end of the pocket. It doesn't have to be perfect as the screws do most of the work.

(Speaking of neck screws, you'll probably need to drill out the body holes so they just match the width of the screws. You only want the screws biting into the neck, not the body and neck, to allow the screws to fully pull the neck down into the pocket).

If you do end up struggling on intonation, one option would be to replace the kit ABR-style tune-o-matic bridge with a cheap Nashville style one from eBay or Amazon. I'd recommend a Korean-made Sung-Il bridge for a good quality vs price compromise. The Nashville bridge was the later Gibson T-O-M bridge design and it gives you a couple of mm extra total intonation travel over the original ABR design (which I believe then allowed Gibson to get away with being less precise with the bridge positioning holes as factory production volumes increased and the workforce became less skilled overall).

**McCreed** · 31-10-2021, 06:19 PM

Technically no. The scale length is defined as twice the distance from the nut to the centre of the 12th fret. You can't get away from that. But the final intonated string length will be longer than the scale length, (which is what I think McCreed was trying to say)

Yes, badly worded on my part.
My point was that sometimes the 12th fret isn't always exactly 1/2 of the nominal scale length and when measuring, checking or setting out the bridge position, the full length from the nut is best rather than half the length from the 12th fret. Clear as mud, right?

The distance from the nut to the 12th fret can vary .5+mm either way and still intonate fine in the end.

Edit to add:
Good call on the neck/pocket mating too Simon. I meant to include that as well!

**Simon Barden** · 31-10-2021, 06:34 PM

We are really discussing semantics here really.

The 12th fret really should be 1/2 the nominal scale length from the nut (or else the quoted nominal scale length should be adjusted to 2x the 12th fret distance). But certainly in affordable kit guitar world, the 12th fret placement can vary a bit. It normally isn't too far out and so it can be compensated for using the intonation adjustment on the bridge. In reality you'll probably get more tuning variations by pressing down harder or softer on the string when you fret.