Official Luthiers Forum!

Hi Everyone.
I've never been in this part of the forum before but I'm now building a tenor uke for a friend and have several questions. I apologize if these questions have been asked many times before but would really appreciate some short answers.

1. I've downloaded plans (14th fret to body, Tenor) from Ultimate Guitar Online. Anyone used these? Are there any improvements people have made?
2. The plans are obviously lacking because I can't find the answer to the next questions: what is the neck angle on a uke? Like a guitar should the line of neck plus fret board and frets just kiss the top of bridge?
3. Is the bridge moved back for compensation? By how much?
4. Does anyone shoten the fretboard for nut compensation? How much?
5. Is the finger board flat or radiused?
6. I've read about Tony from NYC's method of punching the Uke in the face. How much force should I use for this? Does anyone have any equations for how the force of punch affects monopole mobility?

Thanks in advance!

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We are all in the gutter but some of us are looking at guitars.

I think I can help with some of these questions:
1. I have not used them. Sorry. Can't help you with this one. I'm not off to a good start.
2. Yes. There is a neck angle. I don't recall what mine worked out to, but you want the same "kiss the bridge" type of set up as a guitar.
3. On a tenor, the scale length is so short, Compensation is not really needed, but if it makes you more comfortable, you can add some. Like a really small amount.
4.No, so shorten it by zero inches, or zero mm, whichever unit you are more comfortable with.
5. Mine was flat, but some folks might prefer a radius. Flat worked well for my concert uke.
6. You are my hero. I think we all know that Force= mass x acceleration due to gravity, right? I mean, that's basic kindergarten physics, right? Anyway, what worked for me was to use about half of my weight. I am 180lbs, or to put it in your terms, 81.6466 kg. Thus, 90lbs, or 40.8233kg was applied to the soundboard. This works out, using our kindergarten formula above, to 40.8233kg x 9.80665 m/s2(obviously, everyone knows that this is the standard acceleration due to gravity) = 400.33981newtons. There you have it. 400.33981N applied to the face will completely remove the monopole, dipole, and cross dipole frequencies. A new face will restore them, though not to exactly their original values.

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http://www.CostaGuitars.com
PMoMC

Joe,
I have only done 1 tenor from the Hana lima plans, but no neck angle, yes compensate saddle, yes you can compensate nut, flat is common, but radius has been gaining popularity.
This will be helpful from David Hurd:
http://www.ukuleles.com/Technology/compensate.html

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http://shastaguitar.com/
http://www.kalimbakit.com/
http://www.youtube.com/user/comfyfootgr ... ature=mhee
http://www.facebook.com/robert.renick.7

I've made a few tenor ukes so here's my input....
1. Never used them. I like the Hana Lima plans
2. I do about 1 to 1.5 degree neck angle. (can't really measure it that accurately)
3. Yes. I use the calculator at Stew Mac to get the compensation. http://www.stewmac.com/freeinfo/Frettin ... tcalc.html
4. Nope I don't do that on guitars either
5. Mine are flat. Most ukes are flat but radius fingerboards are becoming more "in"
6. HUH??

I recommend the Ukulele Underground forum for more info. Lots of more fanatical builders on there

I'm doing my first uke right now and making it up as I go, so I won't be able to help you from any foundation of experience. I will say that I am disappointed in our resident uke face punching expert (Tony). His response was incomplete and his physics mis-applied.

First he neglected to point out that his numbers were based on a hardwood top and that, if you are using a softwood top, you should decrease your final force applied by a factor of negative eleventeen percent. I know it has been a long time since Tony has been in kindergarten (though it was, by all accounts, 5 of the best years of his life) but that does not excuse his confusion on basic kindergarten physics. He is calculating force based on the acceleration due to gravity (9.8 meters per second per second) but I know for a fact that he did not drop his fist along with half of his body weight in a free fall. Further, he doesn't provide the time his fist would have been falling. . . I have seen him in lederhosen, I think 180 pounds is a conservative number anyway. All of this is to say that I'm pretty sure he made up the math and actually struck his top with the weight of 400.33981 FIG Newtons.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

6. This is good stuff!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I literally laughed out loud at Bryan's post. llol

_________________
http://www.CostaGuitars.com
PMoMC

What Ernie said except I use 15 foot radius front and back.

Bob

I do my tops flat and the backs with 15' radius.

Thanks for the replies everyone.
I now have all the information I need for my new book, "Building the Subservient Uke, Feary and Mis-practise", retailing at $200,000.
So, neck angle to fit bridge, check out Stew Mac for saddle compensation, sod nut compensation, flat finger board and when the laquer is dry get out the Mike Tyson jig for a right hand hook to it's chops to teach the little blighter who is the master.
I'll post some pics when finished.

_________________
We are all in the gutter but some of us are looking at guitars.

Joe,
Neck angle is really a function of the dome or shape of the top, then fit the bridge. If the FB is to lie on the upper bout the way most guitars and ukes are built, then that determines the angle. If you were using an elevated FB like an archtop instrument, then aim toward your desired bridge height. The Stew mac calculator is only dialed in for high G tuning, info for low G is not part of the calculator, too bad for me since that is what I am working on.

_________________
http://shastaguitar.com/
http://www.kalimbakit.com/
http://www.youtube.com/user/comfyfootgr ... ature=mhee
http://www.facebook.com/robert.renick.7

Here's a cookbook approach that avoids the principles of physics that others would bring to bear. Unfortunately, I do not have a calibrated fist, so I am forced to do things the hard way.

The neck angle is 90 degrees. The top rim is first sanded flat. Then put the top rim in a 25' radius dish and radius the rim, but only from about the bottom of the sound hole to the bottom end of the body. In other words, the upper bout stays flat and 90 degrees to the heel and the lower bout gets radiused. Don't worry about a gradual transition from flat to radius as it doesn't matter. Seen in profile, the sides slope down a bit from the sound hole to the end of the body. For the top, make the brace above the sound hole flat and the brace below radiused, as are the tone bars.

The fret board then lies flat on the upper bout all the way to the sound hole and the saddle height ends up at about .40". Works every time for me. If it doesn't work for you, whack it with your fist until things look right.