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Greetings to the classical guitar builders -- I have a question that needs to be answered-
I just received a set of plans to build a Jose' Ramirez classical guitar and the top and back seem to be flat rather than having a radius to it. is this the way it is made?????????
I will be attempting this guitar as soon as I get done making a 12 string dred. that I am working on now.
any help would be appreciated-- and thank you in advance for any replies....
Donald

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I looked into a music shop 3 weeks ago in Liverpool and the salesman told me "Oh No! A guitar should always be FLAT.And he also had no idea what a Flamenco guitar was.Even a young lady overhearing couldn`t believe what he was saying (eyes wide, mouth open) I gave up asking him questions.

But you can have flat OR curved.In Spain they find it is less likely to split in dry weather if there is a curve built in. But they also say that a stronger curve gives a better bass note.
I just thought ,how do you measure an angle to a curved surface.I suppose the contact point of the bridge is the important thing.
Hey Cliff-- Are you going to make a jig to make the classical that you have the prints to??
I haven't figured out exactly how I'm going to go about putting mine together without a jig,
which I think I should have.. I have jigs for dreds. and a couple of other guitars that I have designed my self that are for all intentiona perposes made like a dred. but a different size..
get back to me on this ok?? thanx---
Donald
I really haven't decided how to approach it yet. My game plan has been to build a couple Ukulele's first and get myself up to speed with some of the basics first before commiting myself to a big project with expensive materials. Try a few things on a small scale you might say. I have some more reading to do before I have it firmly in mind. I'm just finishing my workbench and getting all my tools up to speed at this point. Lots of reading to do and questions to ask before I really dive in on the guitar. I have the wood in the shop getting acclimated . The first thing I intend to do is build the side bending fixture. Very curious about your question on cutting the slots for the ribs in the neck heel too. I just hadn't got to that question yet.
Well Cliff - I posted a question to Bob Webster on the subject of making a form,
because it seems to me like the neck is joined to the sides and is an intergal part of the guitar, rather than being set in a dove tail or mortise..
I my self have made many solid body guitars but the making of hollow body guitars is a venture that I have only been involved in for about three years.
This adventure of making a classical is something that I haven't done as yet so with the help of people like Bob Webster I hope tp get this thing off the ground and become a reality..
be safe and have fun in what ever you do--
Donald
I gave Cumpiano and Natelsons book a pretty thorough going over last night and they seem to only use a "workboard" which seems similar to what you can see being used on the Ramirez website pictures of their shop. Charles Hoffmans website has some very nice photos of his jigs tooling and forms all laid out in construction order. That's really something to see. I think I am leaning toward the outside form method myself. It seems to match up with my little bit of violin building instruction I have had so it just seems more secure to me.
AHAAAAAAA Clif so that's how its done... I've seen a few piocs of this kind of form before but didn't give a thought of making one -- sooooo
off to the shop I will go and use the template that I got from LMI and make one of thoes handy dandy forms-- thanx for giving my brain a jolt and the info too..
You're ok in my book..
Donald
As long as you know that you're going to be sticking to one basic guitar shape for a while, there are a boatload of good reasons for working with an outside form. It can be fiddley to set up well but it's worth it.

Cheers,
Bob
Hi, Donald. Sorry to be so slow on this but I was out of town over the weekend. The traditional method for joining the sides to the neck is as you've described it. The neck is slotted to receive the thinned, bent sides and the interior portion of the neck is preshaped to create a neck block with the traditional Spanish foot. Both the neck block and the heel are carved after the slotting but before the sides are fitted in. A ledge has to be cut in the topside of the neck block so that the top will sit on it flush with the upper surface of the neck.

In the most traditional sequence of assembly, the neck is glued to the top before the sides are glued into the neck. Instead of a continuous kerfed lining, little triangular blocks of spruce, called tentellones are glued at the side/top interface using hide glue and a rub fit.

One of the disadvantages of this sequence is that it's pretty difficult to finish the shaping, sanding and French polishing of the heel/body joint. That's why I build a body separate from the neck using an outside form and join it to the neck using a mortise and spline arrangement. I might put up a blog with photos illustrating that method.

Cheers,
Bob
Hey Bob first its ok if you are not like grease lightening in returning in returning a post to a question, because I'm in no hurry to mess this thing up.
I was looking at the print and thought to my self the the back had to go on first because the slot in the side of the neck is NOT cut at a 90 degree angle to the serface of the neck where the fret board attaches.
I was thinking that if I made a solid form and glued the sides to the back then I could just slide the sides into the neck cuts that were made earlier. NO??
Donald
Donald, I'll have to reply here to your note below because, for some reason, there was no Add Reply bar.

Anyway, glueing the back to the sides first is a tough way to go for a couple of reasons. The first is that glueing a properly fitted pair of sides into the neck slot is kind of a stressful exercise in the first place. The glue in the slots tends to dry very fast and lose lubricity so that you have to work pretty fast. Doing that with a pair of sides linked by a back (the end of which has to land squarely on the heel of the neck) would be too much for even the bravest of us.

Also, there is a high risk that the top edge of the sides could end up splayed even if there's absolutely no spring back to the sides.

If the cut for the sides is not 90 degrees, which way does it lean? Some builders used to do that to get a forward cant to the neck for purposes of establishing the right action. However, they manage to get the cut 90degress to the top by using a workboard that has neck support canted at the proper angle to make that happen.

Bob
Bob, Would it be correct then to say that the shimming and the neck extension angle on the workboard are are set up on sort of a cut and try basis to get the proper action height back at the bridge? The 90 degree angle to the top being the constant and the neck angle adjusted as needed? I hope that makes some sense.
Cliff, by "cut and try", do you mean tip the neck to some angle, finish building the guitar, and then see how the action works out? If that's what you mean, that way is >90% sure to break your heart.

How you're going to establish the right action can really only be done by carefully calculating everything or making very accurate drawings to mock up various scenarios. The process for both has to start with determining how much arch you expect the middle of the lower bout to have above the plane of the sides and it can't be theoretical. It has to be actual, because three different luthiers can glue fans onto a top in a 25' radius dish and end up with three different numbers, depending on how they did it and how much springback they get after gluing.

The next piece of information is that there is an optimum height for the top of the saddle relative to the top. The consensus of the very best classical builders is that it should be around 10mm on the bass end and slightly lower on the treble end. That distance + the arch height is a critical measurement.

A second set of critical numbers are the action itself. A good consensus set of figures for gaps between the strings and the frets are these (sorry for the mixed units of measurement): bass 0.030' at the 1st fret and 4mm at the 12th fret, treble 0.020' at the 1st fret and 3mm at the 12th fret.

Next, one has a choice to make between two basic options in preparing the drawings or calculations to establish the action.

Option 1: Manipulate the angle of the neck/bottom of fingerboard using a fingerboard of constant thickness (say 6mm) to achieve the target action. In practice, it will require tapering the fingerboard from the 12th fret to the end for an angled neck.

Option 2. Make the plane of the neck/bottom of fingerboard the same as that of the top rim (i.e. neck joint 90deg to the top). Manipulate the top surface of the fingerboard to achieve the target action. In practice, this would require tapering the whole length of the fingerboard.

If you have a way of conveniently tapering the fingerboard, option 2 is the clear cut hands down winner and beats the hell out of trying to manipulate the angle of the sides slots in the neck. Many big name luthiers use option 2, including the likes of Antonio Marin Montero. I follow humbly in his footsteps on this one.

So, before this becomes Moby Dick, I'll just say Billy Joe Bob says "Check it out!". Let me know how the calculations come out for you.

Bob

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