MIMF

I've seen guitars move so much under humidity changes that back braces have been blown off and, in one extreme case of over humidification, where the back bindings had blown off at the butt end because the back panel had grown nearly 2mm along its length. That same guitar had evidence of gross under...

To my surprise, I read the design book as saying that high impedance sides and a live back could work. Am I reading this right? Well, everything works to some extent, but, yes, high impedance sides and a live back work well, compared to run-of-the-mill guitars. As ever, you can't look at anything o...

Doug, what matters are high impedance mismatches everywhere you don't want a wave to go, like out of the top and down the sides. Keeping the bending waves in the top keeps it ringing. High impedance mismatches reflect waves. Mass helps with an impedance mismatch more than stiffness does. So think ab...

Matthew Lau wrote:I was just thinking of experimenting with black shellac...

I did the one above in nitro. Just getting the pigment here was a major hassle. I got some just before reaching for a rattle can...

That's gorgeous! Thanks! In teh worse case scenario, I'll paint it black. Black paint is not really an easy way out. Most of my finishes are clear, so I asked a few guitar makers who do a lot more painting than me about how to go about a black finish. The unanimous advice was "don't do it"...

Professional guitar makers quite often have a "test mule" guitar or two, which new ideas are tested out on. I have a couple of guitars of different types that have had multiple tops on. If you do a decent job, very few people would be able to tell that a top (or back) had been changed. Her...

Interesting question. Many years ago, in my early experiments with intonation/compensation, I filed the frets on a guitar to a triangular profile (with a triangular file ;) ) with a pretty sharp top. IIRC, I didn't hear much (if any) difference to a normally profiled "new" fret. Recently, ...

...I'm just going to continue making the 000 the way it was intended and plan a classical for next time around. You made the right decision. I've long been of the opinion that most guitars are too big for their own good. A guitar that is 390mm across the lower bout (000 size) is way too big for a c...

If you end up pulling the frets, heating them with a soldering iron first often helps them come out and reduces the chipping. Even with non-oily woods like mahogany, the gunk collected around the frets over the years can be used to advantage...

Alan Carruth wrote:They were Australian imports, with some sort of soft local wood for the B&S,...

I didn't think we did soft!

Most of the stuff around here you can't drive masonry nails into once it's dry!

I wonder why Doug chose to start the iteration by measuring pitch at the 5th fret, rather than a lower one. When I do this "properly" I run an optimisation routine that covers all the frets I want to incorporate (usually 0-12 on strings 4, 5 and 6 and 0-18 on strings 1-3; no point in forc...

Trevor - I am guessing you must have posted something on the subject that clarified things for my friend, as I just got a note from her to the effect of "...never mind - Trevor Gore posted something - got it now'. Yep. The argument goes something like this: Tune the string Measure the cents er...

Frank's method is correct (of course!), as is Jeff's explanation as to why.

Doug Shaker wrote:Just fishing around with the numbers it looks like you want the thickness in millimeters to be the cube root of 190000/[Young's modulus of the wood].

Needs some work on the decimal point .

I'm building a 000 12-fret with a western red cedar top. It's currently just a shade over 3mm thick. I've gotten two conflicting opinions from luthiers about what the optimum thickness should be: one says 3.5 mm and the other says 2.5 mm. What has your experience been with this material? As other h...

Like many of the other respondents, I have so many problems with this experiment that it is difficult to know where to start. I think you're asking the wrong question. I think it would be more useful to ask something along the lines of "How do we market alternative B&S woods so they become ...

Assuming that picture is of #6 and #7, which is which? Guitar 7 with reverse fan bracing and Kasha placed soundhole. #7 on the right, I guess. Guitar Six- DEAD ON spot on in tune all over every fret Try as I might, I have found this impossible to achieve even with my best intonation and compensatio...

Don't build it without an allowance for saddle compensation (if you're not doing nut compensation). I've just fixed a guitar that had the front of the saddle at nominal scale length and not enough room on the saddle to do decent saddle-only compensation. For a standard 650mm scale length you should ...

To a reasonable extent, stiffness (as in Young's modulus) tracks density for the spruces. The flexural rigidity of a panel is directly proportional to Young's modulus and to its thickness cubed. So the stiffness increases very rapidly with thickness, which means that in most cases the low density, l...

It's much more to do with how you use it rather than how much you spend on it.

Lots of good sounding instruments have been made from reclaimed wood that has been saved from a dumpster. Whether you like the aesthetic is a different matter...