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I am (hopefully) about to start on my first instrument, a soprano ukulele.
I have accumulated 3 inexpensive ukes to base construction ideas upon (and to maybe learn to play).
One is the $25 Grizzly 'kit'.. not much to assemble, but it was fun...
The others are a Lanikai, and an Ovation/Applause uae20 acoustic/electric
Anyway... the Grizzly specified a 13 5/8 scale length, and the Lanikai is exactly 13 5/8 inch, but the
ovation/applause is 14 inches!? From the nut to the 12th fret it is 6 7/8 inch, and from the 12th fret to the bridge it is 7 1/8 inch.
For construction, I will use the 13 5/8 length that is specified on all the plans that I have, but this just makes me wonder why the Applause has SO much compensation.
I guess that it could be a construction mistake, however, I would think that they use some type of jig for this.
This makes me wonder things like, how critical is scale length compensation, what might be to advantage of having excess scale length compensation, etc.
I know I am overly obsessed with this, however, any thoughts about this would be appreciated.
Cheers...

13 5/8 (13.625") would be unusual for a ukulele scale length.
14" is actually a concert ukulele short scale length, favoured by some on 14 frets to the body sopranos, or mezzo-sopranos.

Your problem with 13.625" is in finding a ready slotted fingerboard, or indeed a slotting template to make your own. Also bear in mind that the neck length will be different (nut to the 12th fret body joint), with different scale lengths, and that has to be taken into consideration too.

The options and variants... for a soprano ukulele

For 12 frets to the body:
scale length/front of nut to body joint
13.500" / 6.750" (Hana Lima pre cut fingerboards)
13.614" / 6.807" (That's the Martin scale length)
13.750" / 6.875" (Stewmac kit scale length)
13.875" / 6.937" (A "cheat" of a scale length. See note below)
14.000" / 7.000" (Concert neck, short scale)
15.000" / 7.500" (Concert neck, long scale)

For 14 frets to the body:
scale length/front of nut to body joint
13.500" / 7.486" (Hana Lima pre cut fingerboards)
13.614" / 7.550" (That's the Martin scale length)
13.750" / 7.625" (Stewmac kit scale length)
13.875" / 7.694" (A "cheat" of a scale length. See note below)
14.000" / 7.764" (Concert neck, short scale)
15.000" / 8.318" (Concert neck, long scale)

That "cheat" of a scale length... 13.875"...
Stewmac produces a rather nice jig for cutting fret slots into a blank piece of wood. They produce fretting templates for lots of guitar scales, but no ukulele! However, a F style mandolin has a 13.875" scale length, and Stewmac produce a fretting template for that....and so it could be used for a uke with either 12 or 14 frets to the body, and with either 12 or 18 frets!

Rod

Thank you very much Rod, for all of that great information. I did not realize that there is so many possible scale lengths for 12 frets to the body.
Of the ones that you listed, the closest my Ovation/Aplause comes to is the
14.000" / 7.000" (Concert neck, short scale)
Although "front of nut to body joint" is 6.875, and therefore 7.125 from body joint (12th fret) to the bridge... a 1/4 inch difference. And that seems odd to me.
I have a lot to learn. I just need to stop trying to learn everything before I start construction.
Thanks again,
Cheers, Hal

Todd... Martin state that their ukes (including the S-O Uke) have a scale length of 13.614"



That is odd... unless the body join isn't at the 12th fret. Measure the fretboard along its centre line from the nut to the 12th fret to get the right dimension. There's nothing "wrong" with the 12th fret not being at the body joint by the way, it just isn't usual. (In fact, I am building a soprano uke at this moment, which has 13 frets to the body joint).

The "critical" thing though, is that the 12th fret should be half the scale length (i.e. half the string length)... with the following adjustment....

What I didn't state in my figures in the post above, is that there should be a slight difference in dimension from the nut to the 12th fret (7") and the distance from the 12th fret to the centre of the bridge saddle, which should be at 14.083" (±0.030") from the nut rather than exactly 14". That is the compensation factor that needs to be added, assuming a non-compensated bridge.

Rod

Hal,

UKULELES

Yes, there are a number of scale lengths for soprano ukuleles as Rod said. In fact, I found several other scales lengths that weren’t listed. It seems that most sopranos with a soprano size neck range between 13.5” and under 14”.

What ever plans you use will give the scale length for those plans. Unless you are planning on creating your own plans or adjusting on plans you have then you would be all set.

My opinion is that any of the scale lengths will work just fine as long as you slot your fret board appropriately. What you need to remember is that the scale length is a mathematical formulation and is not compensated. That would be between the nut edge and the center of the saddle with the 12th fret being half way. You will need to add a small bit for compensation so the bridge can be placed for correct intonation. Once you choose a scale length you will also need to choose where the neck will attach to the body. Should it be the 12th, 13th, or14th fret? I think that the answer should be made in respect to the approximate bridge location. You wouldn’t want you bridge too close to the sound hole nor would you want the bridge too close to the bottom of the sound board either. You want the bridge to be located in whatever sweet spot you determine to get maximum performance of the sound board. This really plays into plans when using a concert neck on a soprano body. By the way my favorite ukulele is a concert necked soprano. It has a little more playability then a standard soprano but keep the same traditional sound.

David Hurd has a great page on his web site with a jig to measure individual string compensation. It is very interesting. There are a variety of ukulele strings available and each brand has different characteristics. I have not built the jig yet but it is in my plans. After all, you want to maximize the intonation by having correct compensation for individual string sets.
http://www.ukuleles.com/Technology/compensate.html

As far as fret boards go you purchase them precut or cut your own. Allen Guitar and Luthier Supplies have a wide variety of scale lengths for the soprano ukulele with no set up costs. There is a small service fee for cutting the board but since they are set up for the cuts there are no additional set up fees.http://www.allenguitar.com/fret_slo.htm

Bob Gleason of Pegasus Guitars and Ukuleles sells fret slotting templates for ukuleles. He also sells a number of parts also.
http://www.pegasusguitars.com/ukulele_fret_slotting_templates_.htm

My first recommendation would always be to check with Mike or Asa Chock at Hana Lima ‘Ia for any ukulele needs. If you don’t see it on the site then ask for it. You might find that they will have what you need or can accommodate a request. Both of these gentlemen are very knowledgeable and are very helpful. The Hana Lima 'Ia http://www.hanalima.com/

Best of Luck,

Philip

_________________
aka konacat

If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

That's a good call about Hana Lima, Philip. I have dealt with them a few times (from here in the UK). By the way, their pre-slotted fingerboards are for a 13.5" scale, and are LONG! More useful for 14 fret necks, otherwise you tend to start overhanging the soundhole at the other end.

They are also, in my opinion, much too thick and would result in having to have a bridge that is too tall and strings too high over the body, but its an easy task to plane them thinner (before fretting). I simply fasten them to a workboard (fret slot face down) with double sided tape, and then use a good smoothing plane on them, and testing for thickness at each corner and the centre quite often.



You do need to be careful getting it off the double sided tape afterwards as it is fairly fragile. I work carefully using a thin palette knife.



A lot in the proportions of your uke design depends on the scale length and the fingerboard that you are using! Neck length to the body (i.e. length of neck) to get it at the 12th or 14th fret depending on the scale length. The position of the soundhole if using a long fingerboard rather than a 12 fret fingerboard. Then the position of the bridge in the "sweet spot" as Phillip mentioned.

Here's what can happen to the fingerboard using the Hana Lima pre-slotted one on a 12 fret neck and a standard bodied uke. There are too many slots for comfort. And I have already cut the last one off!



This is a Hana Lima fingerboard with the 13th fret over the end of the neck/body joint, with the soundhole marked on it in the normal position, and also a bit further south.



Having said that, buying ready slotted fingerboards saves a lot of work, and also the cost of setting up with jigs, templates and saws to do it! If you go the route of slotting your own fingerboards, then it is worth considering that "cheat" I mentioned above in using the Stewmac jig, with a mandolin fretting template. But be aware that you need to look at the neck length, soundhole position and the bridge position, which will move from your "standard" ukulele plan. Hint... you don't need a store bought ukulele plan, you need a uke to copy, and then still you need to adjust things to fit the scale length you are using. My recommendation would actually be to start with a Stewmac uke kit, which teaches you a heck of a lot about building a uke and its design, and it makes a fine instrument too! This one was my very first uke, from a Stewmac kit, but with a few little alterations.



The ukes that I am now building are sopranos, but to my own plans, and even of a different shape... basically like this... which I based on the shape of my Martin 12 fret to the body dreadnought guitar.



Rod

Thank you Rod, Philip, and Todd for all of this information.. Those pictures are great Rod!.
I have not completely digested all of this info. yet, and now the hurricane is aimed right at Houston, so it might be a few more days...
Having this website, and people like you all to communicate with is going to make construction even more enjoyable.
In regard to cutting fret slots, I ordered the custom fret cutting circular saw blade from StuMac, which I will install in my small table saw, and I will fabricate a fixture, with some type of length indexing to slide against the fence.
It's all going to be fun, thanks again,
Hal