"Longer" neck (14th or 16th fret meets the body) possible?

[Bart van Weperen]

Hello to all here!

 

Still working on my "cuban Très" but now I think I run into real problems.

The sides are bent and glued, back is bookmatched and thinned and soundboard is starting to become a soundboard.

I wanted to know where on the soundboard the soundhole would be and where (approx) the bridge would end up. (Plan was for the neck to meet the body at 12th fret)

So I measured (and measured again) and got confused at first and realy worried later.

The situation is that the center of the soundhole would be just a bit lower than the waist and the bridge would end up about 5 cm (1.97 inch) from the bottom. (see attached picture)

 

The only thing I can think of -in order to get the soundhole and bridge to move up to the neck- is making a "longer" neck, meaning that the 14th or even the 16th fret will meet the body.

The wood I have to make the neck would allow this (it is long enough) as does the "raw"-fretboard.

 

This Très will have nylon strings and I planned for a "3-point" bolt on neck.

I now that accoustics can have the 14th fret meeting the body, but would this also be possible for the 16th, without having to use a truss-rod? Or will this "exaggerated long neck" get me into new problems?

(Neck: Brazilian Cedar, fb: ebbony)

 

Thanks for reading this and if you think you can help/ advise: please do!

 

 

[William F.Eden]

Well Bart I hope you didn't think I was trying to be a smart ass but every thing depends o n what scale you plan on using  on this Guitar.The best advice I or anyone else can give you is to go and have a talk to a fine Luthier and learn all about what the scale meens. And good luck with your build.Bill...........

[Bart van Weperen]

Why should I mistake craftsmenship with "smart ass-ism", William/ Bill? You obviously know what you are writing about and I'm just kind of "walking in the mist with my eyes half shut"... That is why I posed my question.

I would realy love to have the possibillty to talk with and learn from a fine Luthier...but I haven"t. My main responsabillity is to care for my wife (lots of things "wrong" including Lupus) and my doughter (mental and physical dissabillities). I have to be arround, like 24/7. (Don't pitty me! We are doing great!)

I started my own "training", thinking/ hoping it could result in something that could bring in some money (some, not lots) and could be done at home. And of course: I realy enjoy this work.

By now I found lots of info on scale-length, whitch I'm trying to digest.

 

Thanks for your sound advise!

 

[William F.Eden]

Your story is one I couild have wrote myself Bart I am there and beleave me I know were you are coming from. BUT I must tell you that the most problems I have ever had  was in building a Guitar for someone that had a brite idea and it didn't work out.  I can tell that you are up for the job at hand and that you will see it to the bitter end. And beleave me after this Guitar is done you will have a better understanding as to what not to take on in the future .  Your freind Bill..........

[Ned Knepp]

From the research I've done on these, 550mm would be on the long end of scale length for a Cuban tres.  I've seen overall measurements that only go to 850 mm so it seems to me that a 650 mm neck is much too long. I've also been under the impression that most of the instruments in this family tend to have the body/neck joint at the 12th and lower frets. Most of the Cuban tres I see here are joined at the 10th fret. 

That's not to say that you can't build your's differently but I think the problem you have with sound hole and bridge placement is that you are using much too long a scale length.  

At this point, it might be better to determine the approximate bridge and hole locations and see what that does to your scale length.  If you have the bridge location you can play around with 12th fret placement to determine how long the neck needs to be and what attachment point works best. 

I don't know how you are bracing this but that shouldn't be forgotten when you consider bridge placement.

[Tim Mace]

Somebody else chime in if I'm far off base but imo all you do to shorten the scale length is cut off at fretslot #1.You can measure before cutting by determining where the new 12th fret "will" be and apply that measurement to where the new bridge placement should be.It will be approx 1/2 the distance or about an inch forward forward of old calc.I've done this and it worked for  me.Or... figure out where you want the bridge to be and order a new fretboard for a desired scale length!  Seems like removing the first 2 frets would be even better but don't listen to me til' someone else agrees but it is best to "know" before cutting.If I've confused you don't do it!

[Bart van Weperen]

I once asked the guy I'm building this thing for if he had any idea on what strings he would preffer to use. He mentioned "pyramid" and those are made for a 55 cm scale lenth.

If I had sticked to the original design ("normal" guitar shape) this problem wouldn't have occured, but I lowered the neckblock-section by some 8 cm (hence the "odd" shape) , and I then forgot to check the overall-design. Not a mistake I think I will ever repeat.

Thank you also for pointing out the need to re-think the bracing.

(This was supposed to be a response to Ned, but the site put it where it now is...)

[Tim Mace]

no more than two bolts will suffice...less possibility of weakening...what type bolt system?be sure and visit William Cumpiano's website for ways to bolt and his notebook archives is a must read! imo

 

[Bart van Weperen]

I found info on scale length, now I have to start "digesting" all that...

 

Not too long ago I tried to bring an unplayable brand-less archtop back to playabillity. There I used a 10 mm bolt and nut and a 13 mm b&n. (The "nuts" being about 25 mm long with also thread on the outside).

That neck is still firmly (and ok) connected to that body, so I was thinking on using that. I also thougt that 3 B&N's

(2 next to each other at the top-side and 1 at the bottom-side) would improve stability (keep the neck nicely in position to the centerline). I could use "thinner" B&N's...

But: I'll take your advise to heart and will start re-reading Cumpiano and also check out Taylors bolt-on system...

Thanks!