MIMF

Over the years I worked out a system for ensuring accuracy when marking fret slots by eye. The old adage says 'measure twice, cut once', but I realized that there was an issue with that; basically, if i mis-read the rule once, it's likely that I'll mis-read it again in the same way . The trick is to...

If you want the wood to reflect light it's best to use a clear colored finish, rather than dying the wood. Dyes are effective (in a way) on figured wood, since they enhance the contrast, but they do it by soaking into the exposed end grain more. The 'stripe' of curly maple becomes more pronounced as...

Marshall Dixon asked: "Can we say that increasing stiffness decreases damping?" No; actually, it's the other way around, sort of. Increasing the bending stiffness at low frequencies by arching the plate produces lower effective damping by shifting their resonant pitches upward. First, I ma...

Any extensive system will have a number of different modes of vibration, theoretically as many as the number of elements it's made of. Thus a line of ten coupled pendulums will have ten possible modes of vibration. A guitar top is a 'distributed' system, with theoretically an infinite number of elem...

One person slots a narrow board of some hard wood that is thicker than the fingerboard they're making for each scale. Then they cut off a strip from each, I'd guess about 3mm wide, and stick them onto the sides of the board to be slotted. This gives a guide along each side for the saw. I have yet to...

The iron acetate solution reacts with tannins to form the stable black iron oxide. You need both parts; just as with using epoxy. Oak has lots of tannins and works great; maple doesn't. 'Tea' made from quebracho, hemlock ,or oak bark can be used to add tannins to the wood. Even plain black tea helps...

Back in the 80s some folks from the Catgut Acoustical Society worked out a 'synthetic spruce', using unidirectional CF on a core of card stock. The resulting composite had similar stiffness to spruce long and across the grain, and about the same damping. They made both guitar and violin tops from it...

You can grind, sand, drill, and tap carbon rods, and cut them with a jeweler's saw, or (surprise!) a knife, but that's about it. They are not kind to any cutting tool, in any event. Do not try to run one through a power saw, joiner, or planer. If you need a custom size you could try making one using...

Vinegar is a very weak acid; it takes more than a few days to get a usable solution for staining. If by 'resistance' you mean the 'stiffness' of the wood, I'd say no, but that's not based on data. At any rate, the dye probably would not work on a soundboard, since none of the softwoods I know of hav...

In some cases, where the bolt-on hardware is heavy on a light body, the added mass can drop the 'neck' resonance pitch, and alter the feel, and maybe the sound. Using lighter hardware instead of cross dowel nut and 1/4-20 furniture bolts, can help.

Don't feel too bad; this is always the hardest part of making the guitar for my students. The important thing is to make one surface (usually the shoulder of the guitar) to the final shape, and then fit the neck to that without taking more wood off the body . Do one thing at a time: align the neck w...

I'll note, too, that different species of maple vary in this. Rock maple tends to give a bit of trouble, soft (European or Red) maple in general a bit more. Broadleaf maple is sometimes good, but more often it will chip, crush, or tear out, when cut along the grain. Even a razor sharp scraper can gi...

The figure is caused by periodic changes in runout, so sometimes you're cutting with the grain and sometimes against it as you go along the grain. Violin makers often carve across the grain to avoid this, and finish up with scrapers and sandpaper. With birdseye that's not an option: there's no 'good...

In theory, you can soften Titebond joints with water, but I've always found that the wood goes to mush before the glue lets go. When you can use heat that will work as well, as anybody can attest who's left an instrument in a hot car... Acetic acid will break down Titebond and similar glues. I once ...

Top braces below the bridge can probably be feathered out to nothing, but the ones above the bridge are under some download, and I feel they need to be left with some height at the ends, and inlet into the liners. Gibson used to feather them all down to nothing at the very end, but they had a little...

Guitars are not made to be disassembled, even if they're glued with hide glue. I've successfully used hide glue for everything at one time or another. I suppose if I kept at it I'd be more used to it, but I've opted to minimize some hassles.

That depends on how sensitive/critical you are. It's easy to make the hole smaller, and a few experiments along those lines can go a long way toward giving you a feel for this. Get some foam core poster board and cut a circle out of it that will just fit the sound hole of any guitar you have. It doe...

Yes; leaving a small gap at the ends does limit the amount the brace ends will push out the binding and the sides. This is a very common problem on old guitars. Admittedly, you won't have to deal with it, no matter how good your warranty is, but still.

Long-grain stiffness at a given thickness tracks the density pretty well, on a more or less linear basis. Stiffness goes as the cube of the thickness. Using a low density top wood, and leaving it thick enough to get the right stiffness gives the lightest top and the most sound. OTOH, top weight prob...

Most steel strings have two more or less parallel 'tone bars' below the X braces in the lower bout. Guild used three.