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Pete Howlett
11-17-2014, 06:56 AM
Rather than post this to individual builds I thought it better to offer some council in a separate thread.

Many of the images of recent builds that have been posted here appear to have what I would consider to be high saddle. If you have a saddle that is getting beyond 0.125" above the top of the bridge I would venture to suggest that this is too high. If you wish to avoid this and have the preferable 0.110" above the top of the bridge you may want to consider these Pete Howlett workshop rules:

Avoid introducing a neck angle*
Use a fingerboard that is at least 0.220" thick
Use a bridge blank that is at least 0.280" thick
Make your saddle slot 0.075" shy of the base of the bridge - make it as deep as possible


I'm sure other makers have useful pearls of wisdom for this most essential thing to get right.

*Neck angle is only necessary on some guitars, banjos and resonators...

Keep posting - I love to see amateur builds.

finkdaddy
11-17-2014, 08:33 AM
Pete, that is excellent advice and it's very timely for me as well.
Thank you!

~Fred

UkulelePlace
11-17-2014, 09:50 AM
Hi Pete,

Can you describe what neck angle does, and why it's not required for most ukulele builds?

Cheers,
Jack

Pete Howlett
11-17-2014, 10:31 AM
Neck angle is sometimes required on a guitar to give an appropriate bridge height usually around 0.350" - 0.375"; on a resonator, to keep the saddle height as low as possible to minimise forward forces that cause cone collapse. The effect is to raise the strings at the saddle. There are other reasons often put forward to do with string break angle and downward pressure which I neither understand and possibly because of this ignorance, nor agree with - I have over 100 killer guitars under my belt, non of which have a 'kick' at the body join. Maybe John Calkin can give his views here....

Anyway, the whole purpose of minimising neck angle in ukulele making is to reduce bridge mass. A properly built ukulele with a radiused front will already reduce the need for a high saddle or fat bridge. It's just common sense and an understanding that you are making ukulele NOT guitars: they are 2 different disciplines that only look similar... ask any guitar maker who is tasked to build ukulele :)

DennisK
11-17-2014, 11:10 AM
So .280" bridge + .110" saddle means you shoot for .4" string-height-at-bridge?

Pete Howlett
11-17-2014, 11:15 AM
No - I aim for a 2.75mm string height at the 12th fret.

Kent Chasson
11-17-2014, 11:22 AM
This is an area that is always frustrating to talk about because of terminology inconsistencies and general misunderstandings about geometry.

Pete, are you really talking about saddle height or string height off the top? Or both?

My primary concern is string height off the top because that's what determines torque (a primary influence on tone and structural integrity). At the same time, I don't want the saddle to extend too far above the bridge but that is only to eliminate long-term deformation or cracking of the bridge slot.

Neck angle is something that I find almost impossible to discuss on line because one has to assume too many things to even think of it in terms of an angle. What angle? What reference plane? Thickness of fingerboard? Top doming? Those things and a few more need to be understoond before the idea of neck angle is meaningful. I always tell people to start with the string height they want and work backwards.

Pete Howlett
11-17-2014, 11:33 AM
Kent - If you read my posts I talk specifically about saddle height above the bridge! I only mention string height as it refers to the usual standard of measuring over the 12th fret and in response to a question. I have re-read all three posts and think I have been very precise and clear in my definitions and descriptions.

Please don't turn this into a spitting contest!

Kent Chasson
11-17-2014, 01:07 PM
Pete, no spitting intended from me but I do drool sometimes. I did read and re-read your posts (and mine) before ever hitting the submit button.

As I said, there are at least 2 possible reasons why one might be concerned with a tall saddle and it was not at all clear to me from your post what your concern was. I have no doubt that you understand all the issues quite well but I also know that there is often a great deal of confusion about this topic. My only goal in posting was to clarify what your concern was and to add my "pearls of wisdom". No slight intended.

sequoia
11-17-2014, 07:09 PM
I actually really like this thread and Pete, I don't think Kent meant any disrespect. He was just making a point I think.. This is a subject that they have been talking about I'll bet since about 1600 and the answers are not easy. I've been scratching my head about this since I started playing guitar 45 years ago and have still not figured it out. I've ground down a lot of nuts and saddles. Sand, sand, sand, shim, shim, shim, file, file, file...

Now here is my take: A mediocre uke with a good set-up will sound better every time than a great uke with perfect wood with a crappy set-up. Hands down, the set-up is the most important step in building an uke. It is an art and a science at the same time and that is never easy.

My two cents: Neck curvature (or whatever fancy word you want to call it) is not really an issue in the equation when it comes to ukes like it is in guitars which really simplifies the situation. Short neck/low forces/flat plane. So we can throw that variable on the scrap heap. This takes out the radius part of the equation making things simpler because the two variables are now linear - nut to saddle does not include an arc.

Anyway, I did an experiment the other day and radically reduced the nut mass by sanding it down to low profile and low action while not lowering the saddle at all to see what happened. Strange things happened on my uke. It went like this: As the nut got thinner and lower, the volume decreased and the sustain increased as would be expected. The action become more and more comfortable to me (as a player not a builder) until... a real break point happened when approaching really low, perfect action. Volume and sustain fell off the cliff. I was a little surprised.

Conclusion: I am confused as usual, but by going past the sweet spot with the nut, I now know where the sweet spot is between sustain and volume and can sand down to it without going past it with the next nut.... Seriously, set-up is everything. A real art. Please wouldn't it be nice if a pro could tell us how to do it.

Pete Howlett
11-17-2014, 10:59 PM
I forgot to say - builder's mojo needs to be factored in!

Wildestcat
11-18-2014, 12:36 AM
Pete - apologies, but I can't work in inches anymore! Hope you don't mind, but for the benefit of other like minded souls I have converted to SI units to the nearest 0.1mm :D

I have been using your top curvature, zero neck angle, fingerboard thickness, bridge thickness, saddle height & action recommendations since my course with you a couple of years ago, and can vouch for the ease of construction and repeatability of results achievable every time. Excellent info - thanks.


Rather than post this to individual builds I thought it better to offer some council in a separate thread.

Many of the images of recent builds that have been posted here appear to have what I would consider to be high saddle. If you have a saddle that is getting beyond 3.2 mm above the top of the bridge I would venture to suggest that this is too high. If you wish to avoid this and have the preferable 2.8 mm above the top of the bridge you may want to consider these Pete Howlett workshop rules:

Avoid introducing a neck angle*
Use a fingerboard that is at least 5.6 mm thick
Use a bridge blank that is at least 7.1 mm thick
Make your saddle slot 1.9 mm shy of the base of the bridge - make it as deep as possible


I'm sure other makers have useful pearls of wisdom for this most essential thing to get right.

*Neck angle is only necessary on some guitars, banjos and resonators...

Keep posting - I love to see amateur builds.

jcalkin
11-21-2014, 04:12 AM
Pete---I came at this a little differently than you did, but essentially by the same reasoning. Soprano uke, no neck set, fretboard .187" thick, frets .040" tall, bridge .250" thick. In theory, if fretboard+frets=bridge thickness, the saddle height could nearly lay the strings right on the frets or as high off the frets as you like. However, instrument distortion from string tension alters the plan slightly, enough that a pleasantly low saddle gives about .80" of string clearance over the 12th fret.

This plan seldom works on a steel string guitar, at least not for long. The higher string tension and longer scale permit the instrument to distort enough that a saddle of proper height leaves the strings too high off the frets. A little neck set allows a tall enough saddle that as the instrument distorts over time the saddle height can be reduced without getting too low. Its pretty common in old guitars to find that reducing the saddle height wasn't enough to lower the action to a playable state, so the bridge has also been planed down and the saddle height reduced to the point of leaving a scant break angle to the bridge pins. Its a much cheaper fix than a neck reset, but it spoils the sound producing system that was initially built into the guitar. Plenty low end guitars need a neck reset when brand new, indicating that the designers didn't know what they were doing or didn't care.
I've seen the same problem in old baritone ukes. I don't know about tenors. Properly made sopranos seem immune to this, at least mine do. Perhaps I need to build them a bit lighter.

Body distortion is common in well-made guitars and should be planned for. I've made at least two very lightly constructed guitars that required major neck resets at first stringing, but after adjustment they were real cannons with rich tone. They also preserved a fine action for as long as I was able to keep track of them. If I had stressed the guitars with weights during the initial neck fitting they might have been fine, but that was decades ago and I hadn't learned about the practice yet.