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As truckjohn says; it's distressingly easy to make a really bad guitar from really great wood. Factories do it all the time. A good luthier who knows what they're doing can make a very fine guitar out of almost anything. Those of use using a 'technical' approach seem to have found out enough to 'raise our level of mediocrity', as my violin making teacher used to say. But there's no recipe, 'magic', 'technical' or otherwise, that anybody can give you that will automatically allow you to turn out 'great' instruments. Some folks work all their lives and never get past 'pretty good', and others seem to hit 'great' with their first one (at least, to hear them tell it). There's only one way I know to find out which side you'll be on, and that's to make some instruments.

Well fellas I've got to say this is one of the most interesting threads I've read on this forum. Seems as though everybody chimed in. In 1989 I was working construction when we had what is commonly known as an economic downturn. Basically what I'm saying is I lost my job. Now unemployment checks are fine for awhile but pretty soon I began to get nuts. I'm not the kind of person who can just sit and do nothing. So I was reading in a magazine about order this book and learn to make a fiddle. I ordered the book as I've played strings my entire life. A fiddle being one of them so I decided I was going to make a fiddle on my off time. After reading the book I immediately knew how stringed instruments were made. So I didn't have any tools. A pocket knife file etc. in a 2nd hand stores outside junk I found an old coming apart at the seams Solid Maple coffee table. In an antique store I found a small length of some kind of fence post but tight grained and really nice. So I started building little bitty mandolins with only four strings. Now when I say pocketknife and file I mean it. I did add a flea market plane. I had lots of fun made three of those small Mandolins. I still have one but it's got a big old crack in the top. Hell it was Arizona what did RH mean to a guy like me. Yes a guitar can be made out of just about anything.
A while back a friend of mine whose family has lived in these Cumberland mountains for two hundred years brought me over a banjo that had been living behind his fathers bureau since his grandfather had died and given it to his father. Now I was curious to see this instrument. Yep it was definitely homemade with a storebought ring. Now I gave it a good look over. It had hand carved Ebony tuning keys. He was missing on tuner. I gave him some Ebony and roughed it out for him on the bandsaw. So he could carve the fourth tuner. It was such a cool instrument.reminds me of the old fiddlemakers who traveled until they found someone who wanted a fiddle. The price? Room and board until the fiddle was complete. You still see old Appalachian instruments around here. I guess you could make an instrument from about anything? Balsa wood? You mean that stuff we built model airplanes out of? I bet it'll fly


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Almost all of the discussion has been regarding tops and bottoms. However, that got me to wondering about bracing and kerfing materials. Being that I am just a beginner I was thinking what would happen if I made my kerfing out of cherry or maple? Then I got to wondering about bracing material. Would hardwoods again like cherry , maple or walnut work for bracing? I have a bunch of cherry. I have spruce which is what I was planning on using for the bracing and mahogany for kerfing but I was just wondering why these seems to be the preferred woods and other woods, such as some hardwoods would not work as well for bracing and kerfing?

Hope I am not clouding or mudding the water but this topic got me to wondering so I thought I would ask about woods used internally in a steel string guitar.
Chuck

Linings can be just about anything, though being in the area that takes the most impacts from accidentally bumping the guitar into things, brittle woods should probably be avoided.

For bracing, spruce is pretty much ideal as far as solid wood goes. It has great stiffness to weight ratio, fairly high strength, and it doesn't split easily. Strength determines cold creep rate. Western redcedar braces can be lighter than spruce at the same stiffness, but will creep faster because it has lower strength. It also splits easily.

Laminated braces are something I've been toying with lately. Assuming you carve to triangular profile, most of the stiffness is focused in the center. The outer edges are really only there to hold the center upright. and provide glue area to the plate. So if you use a strong hardwood like purpleheart in the center, and spruce or Spanish cedar or maybe even western redcedar for the outer edges, it will gain the creep resistance of the strong center wood, without being a whole lot heavier than solid spruce braces of the same stiffness. Haans has been doing this for years, using rosewood or wenge as the center laminate, so go check out his build threads

From my browsing of stats on wood-database.com, the best looking ones for the center are purpleheart, bubinga, wenge, macacauba/hormigo and jatoba. All have great Young's modulus and modulus of rupture relative to their weight.

For USA woods, black locust and persimmon are probably the best. Or maybe osage orange, but I don't have any hard stats on it (EDIT: Oh, they did add stats. Looks half way decent, similar to rosewood). Black walnut has a little higher strength than spruce, but I question whether it would really resist creep better, because it heat bends so much more easily. Cherry doesn't look good. There are many species of maple, but none look good enough to be worth the higher weight and difficulty of laminating. And pretty much any hardwood will have a weight penalty compared to spruce if used solid.

Thanks so much all of your answer makes me understand much more than I did. I just knew I was going to use spruce for the bracing and mahogany for the kerfing but I didn't really understand why that is what builder did. I assumed there had to be a reason but being new to this I thought I would ask. Thanks again. Chuck

Generally, for liners, you want a wood that's not too dense, glues well, and resists splitting. Lots of things have been used, such as poplar, butternut, basswood, and willow (one of my favorites), as well as spruce, cedro, and mahogany. Unless you're using solid or laminated liners the actual strength of the wood is probably less important than how well it glues, and how tough it is. Laminated liners can take a significant load themselves.

I've used walnut and butternut for back bracing. Although the 'job' of a brace is to add more stiffness than mass, it does seem to me that adding mass on a back is not always a bad thing. If light backs were always better, we'd all be using spruce or WRC for backs, but we don't. Anyway, a lot depends on how you think of the role of the back in sound production, and structure. There are different philosophies here, as everywhere in the guitar, and all of them seem to work for somebody.

The reason top bracing is generally made of spruce or some other conifer is because of the weight. Hardwoods like cherry are heavier and may be proportionally stiffer, but in a brace where the height can be altered, you will achieve a better stiffness to weight ratio with a lighter wood. Stiffness is proportional to the cube of the height.

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John

One thing you need to think about is just how much mass you're talking about, and where it is. On both tops and backs most of the mass is in the plates, with a smaller percentage being the braces. ALL of the braces and the bridge plate taken together might amount to 1/3 of the weight of a top. Shaving 10% off the mass of the bracing saves you 3% of the top weight, so it's hardly a game changer in that respect. You do need to have the right stiffness (whatever that is), and enough glue area to keep body and soul together, so to speak, but it doesn't seem to be worth going to great lengths to lighten up braces. I use spruce for top bracing, and agree with John that something like cherry would probably be too heavy there. However, I don't spend a lot of time trying to get the lightest brace wood I can; rather, I use what I've got, start with it over size, and then shave it down to get the whole structure to the correct stiffness.

It DOES seem to me to be worthwhile to spend some time figuring out how thin you can get away with making the top you've chosen to use, since that's likely to save a worthwhile amount of mass. That means coming up with some way of measuring the top stiffness, particularly along the grain, even if it's only 'by feel'.

Will have to finish my Balsa guitar someday. In the mean time how about Pine for the box and a spruce neck. Quite light. Thought it would be best to use a hardwood for the fretboard, ebonized some Walnut. Will do the finish and fret it in a day or two.

I did solid linings on my last 2 guitars because I didn't want to pay the money for the pretty sawn strips and I couldn't bear the idea of cutting 1-million slots into a board just for that... I just sawed up some solid linings out of easy bending wood... Worked out fine...

I would say my #1 concern for solid linings is ease of bending... Most woods that are easy to bend are also easy to glue - so reliable glue joints hasn't been an issue for me...... I can't easily get ahold of willow - so I haven't used it... but Oak, maple, cherry, hickory, and every other easy bending wood work great.... I think I might go for a wood that's slightly easier to work than your sides - just for convenience... As you might imagine - Oak linings may not be your first choice in this regard - though you can reliably bend it at over 1/4" thick....

As you might imagine - this goes back to point #1, though... You learn building by building....

One of the best exercises I did to get the hang of jointing tops was to "Joint" a whole bunch of thin strips of wood and glue them up into "Tops"... I resawed a 2x4 into 3/8" thick pieces and jointed them together into tops... I made 2 tops that are around 16 pieces each... I ended up cutting about half those joints back apart and redoing them to get my technique sorted out... By the end of that - I had the hang of making good top and back joints.... but the whole exercise cost me the price of one 2x4.... I still have those "tops" laying around - I will probably build a guitar out of them just because... If only I could find another Esteban to retop with one

Thanks