Compensation

I have built 5 guitars and am in the middle of my first uke. It is a copy of a Ditson soprano, Style 3, in Osage Orange.

Question is this - the saddles will be straight across (no compensation) but I believe I need to extend the string length just a little from the actual scale length of 13-5/8". On a guitar of conventional scale lengths it is about 1/10 inch at the high e string.

What do you all do.

Thanks

Ed

ruby50 said:

I have built 5 guitars and am in the middle of my first uke. It is a copy of a Ditson soprano, Style 3, in Osage Orange.

Question is this - the saddles will be straight across (no compensation) but I believe I need to extend the string length just a little from the actual scale length of 13-5/8". On a guitar of conventional scale lengths it is about 1/10 inch at the high e string.

What do you all do.



Thanks

Ed

Click to expand...

the Stewmac fret calculator says 13.705 inches for a 13.625 (13 5/8 )inch scale. https://www.stewmac.com/FretCalcul

ator.html

2mm will be near enough.

Thanks all

I did not know that there was compensation at: https://www.stewmac.com/FretCalcul

Ed

Just keep in mind that although the numbers look precise, these things are merely approximations and ultimately an average compromise. Good enough? Yup....

One question: Osage orange? Send pictures!

The sad thing is that some of us test and adjust the compensation at the 12th fret and rarely play past the third.

You know, of all the operations in lutherie that I can think of, wouldn't fret kerf cutting be best cut by a laser set-up? Ruby lasers and rosewood. Smokin. Ummm.... perfect to the 0.0000012 of a mm. Zip..zip...zip. However for the rest of us mortals, a saw must do. But really, isn't this a perfect application for a laser and CNC?

Ok, now you may have solved the fret cutting problem that has kept me from playing with building my own uke.
I happen to have a friend with a laser. I'll start testing w some ironwood. Might take a while though... Busy

Sorry guys but all that will make you is accurately temperedly wrong.
All frets are a compromise aimed at making the degree they are out of tune tolerable. If you want to be in tune there are not only different spacings for what key you are in but there are even different spacings for different types of scale.
The dulcimer people seem to be the ones to take this seriously.
https://sites.google.com/site/peacefuldavesstuff/home/fret-spacing-calculator-for-luthiers

sequoia said:

You know, of all the operations in lutherie that I can think of, wouldn't fret kerf cutting be best cut by a laser set-up? Ruby lasers and rosewood. Smokin. Ummm.... perfect to the 0.0000012 of a mm. Zip..zip...zip. However for the rest of us mortals, a saw must do. But really, isn't this a perfect application for a laser and CNC?

Click to expand...

Maybe. Accuracy of each fret slot to near 0.2 - 0.3 mm's is deemed more than good enough. That kind of accuracy isn't too difficult to achieve with a non cnc set up. In real engineering terms accuracy to 0.3mm's would be the equivalent of aiming for the Moon and hitting Mars. Even if you got the odd fret out by 0.5 mm's there are ways to doctor the fret to get it back into line, better that you don't position it that far out in the first place.

Titchtheclown said:

Sorry guys but all that will make you is accurately temperedly wrong.
All frets are a compromise aimed at making the degree they are out of tune tolerable. If you want to be in tune there are not only different spacings for what key you are in but there are even different spacings for different types of scale.
The dulcimer people seem to be the ones to take this seriously.
https://sites.google.com/site/peacefuldavesstuff/home/fret-spacing-calculator-for-luthiers

Click to expand...

We know all this. You aren't telling us anything new, this is all well understood and has been for years. We are working within a system that allows folk to play in all keys. It's a compromise, we know that. Nothings perfect. We work within that framework and for the vast majority of folk it's perfectly acceptable. Your dulcimer quote is just complete nonsense.

I have been asked to post a shot of the osage orange:

https://www.flickr.com/photos/ruby1638/26127489931/in/album-72157662606115293/

A few shots later you can see the finished binding/purfling. I will post the whole thing in a couple of weeks when it is done.

Ed

I sometimes think I should have picked the Ditson style to copy..It's construction is exactly the same as the Martin but! the waist bend is much easier to accomplish with less breakage (there must be a story and reason for that). Here are a few examples of the Martin Ditson.http://theunofficialmartinguitarforum.yuku.com/topic/172070#.VxnOizGotZo

The whole story about how the Ditsons designed the Dreadnought guitar and uke at the same time and Martin built both of them is fascinating. The shape of the body has a similar waist to the Spanish style guitars that the Ditson stores sold at the time.

Martin thought that the guitar had too much bass and did not build it for themselves until 1933 - 34? when bluegrass came along and they needed a guitar to compete with banjos and fiddles. My hearing is not so good, and I can't readily tell a difference in Dreadnought and Standard ukes from listening on the interweb through my 1/2" speakers - does the body shape make much difference in the sound? Any opinions about what the osage orange ("poor man's Brazilian Rosewood") will sound like?

This and the next shot show the differences in Standard and Dreadnought:

https://www.flickr.com/photos/ruby1638/25080353151/in/album-72157662606115293/

I will probably only build this one uke, and the Style 3 Dreadnought appealed to me. My daughter has a standard Style 0 Martin with a "Wurlitzer" stamp on the head, and I used it for most measurements

Ed