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SamWise
10-06-2008, 01:24 AM
My new Mahalo sounds quite good, amazingly good for the price, but it has an intonation issue. 3 of the 4 strings are good enough for me to live with, but the E string has a serious problem all the way from the 2nd fret onwards. Of course, I can and should file the nut slots and also the saddle to lower the action, and that ought to help, but here's the rub. The saddle is split-compensated, so there is a slightly different scale length for each string. The G and A strings are near perfect at least as far as the 5th fret, but the C and E are off. What can I possibly do?

SamWise
10-06-2008, 03:57 AM
If I move the crest of the saddle, won't I also reduce its height, since by filing I'll remove material? The intonation is sharp, btw. I'll post a closeup of the saddle with its irritatingly complex yet not-working split compensation a bit later.

SamWise
10-06-2008, 06:36 AM
Well, if I have to remake the saddle, at least I can get the intonation right! I know I'll need to reduce the height at the saddle, so if I can adjust the scale length too, that's all the better. I wonder where my needle files are.....

I'm not sure how well this shows the saddle, but here's a picture:

http://i14.photobucket.com/albums/a322/Samuelw72/PA060012.jpg

Ken Middleton
10-06-2008, 07:50 AM
Don't cut, chop or file anything until you have checked whether the string has stretched unevenly or not. If some strings are in tune with themselves, others should be too.

Strings get stretched unevenly when people pull them with their fingers when they are putting them on to speed up the playability. This often stretches part of the string. It usually happens with the A or G. People stretch them too much.

My concert Kanile'a arrived like this and it completely freaked me out until I realised the problem.

KEN

SamWise
10-06-2008, 10:44 AM
Hi Ken - I haven't done anything to cause them to stretch unevenly. However, what that picture is supposed to show, but fails, is the the saddle is split compensated. That is to say, it's shaped different for every string. I've seen guitar saddles which are different for two of the strings, but never anything like this. Each string has a marginally different scale length, longer for the lower notes. Odd.

Ken Middleton
10-06-2008, 11:02 AM
Hi Ken - I haven't done anything to cause them to stretch unevenly. However, what that picture is supposed to show, but fails, is the the saddle is split compensated. That is to say, it's shaped different for every string. I've seen guitar saddles which are different for two of the strings, but never anything like this. Each string has a marginally different scale length, longer for the lower notes. Odd.

Strings sometimes stretch unevenly for no apparent reason.

Compensated saddles are not really needed. They are used to compensate for the differing thicknesses of strings. It doesn't look to be a problem.

Howlin Hobbit
10-06-2008, 01:13 PM
Each string has a marginally different scale length, longer for the lower notes. Odd.
Not odd. Correct. At least, if done right

Compensated saddles are not really needed.
Sorry, Ken, that ain't necessarily so. A well-done compensated saddle will make a world of difference in the intonation, especially up the neck (towards the "dusty end of the fretboard") and even more so on a smaller instrument like, say, a soprano uke.

All that being said, SamWise... go ahead and change the strings. Sometimes (no matter what the brand) you just get a bum string. So try the relatively inexpensive and definitely non-invasive string change before breaking out the files and sandpaper and such.

SamWise
10-06-2008, 08:06 PM
I'll certainly change the strings, but at present, you could drive a truck under them, so I think I'm going to try to lower the action too. The frets are a little like railway sleepers, which means that my big, unschooled, used to steel-string hands also tend to sharpen notes by pressing down too hard, which is only exacerbating the problem (I've checked the intonation in concert with pressing as lightly as possible, and it's still out of whack)

thesoobz
10-06-2008, 08:08 PM
so the action is to high?

why not just file it down bro? works pretty good!

SamWise
10-06-2008, 11:16 PM
Well, if I'm going to file down the saddle, it actually makes sense for me to try to normalize the intonation too. Whether I'll try to cut the slots deeper on the nut, or just remove it and file the whole thing down, I don't know. I'm glad to be trying this stuff on a 12 instrument!

Howlin Hobbit
10-07-2008, 06:35 AM
...my big, unschooled, used to steel-string hands also tend to sharpen notes by pressing down too hard...

Assuming this is a soprano, one thing that will help with that problem is getting concert gauge strings for it. The little extra tension helps and also adds a wee bit of volume, especially to a cheapie instrument.

I recommend going for Aquillas.

SamWise
10-07-2008, 12:10 PM
That's interesting. I would've thought strings designed for a longer scale would be LOWER tension when they were on a short scale instrument. If I were going from a long scale guitar like my Fender Jazzmaster to a shorter scale like a Les Paul, I would expect to need heavier gauge strings, which come up at a higher tension.

SamWise
10-09-2008, 05:10 AM
Hmm. Dug out my needle files, and I don't have anything skinny enough to cut the slots deeper on my nut. I guess I'll have to take the nut off, file some from the bottom, and refit it, but I don't feel as confident of my ability to do that well and uniformly.


What I can do is file the saddles. I can get a little more length on the E string, which is the sharpest. I could do loads on the A, but it doesn't need any. The C I'm not sure if I can move at all, and that's a little out, but I can improve things, I guess. I have a set of Ko'olau Gold strings on their way, so I guess I'll do everything I can to fix the intonation with the current strings, then put the new ones on.

Howlin Hobbit
10-10-2008, 10:25 AM
...I guess I'll do everything I can to fix the intonation with the current strings, then put the new ones on.

The problem with that is that different strings will intonate differently. I've read several luthiers comments on how they set up a uke to intonate with whatever strings they put on them and changing the strings (that is, brand of strings or gauge or whatever) will change the intonation, at least a little.

SamWise
10-10-2008, 10:37 AM
Huh. Well, since I can't get it perfect with the file, I'll just have to hope that the Ko'olau Golds will finish the job! It's much better already, I can stand to listen to myself play it now.