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Hello All I have been using Ted Bergstrand's online nut calculator on Benchmuse.com which is excellent. It allows you to have a consistent gap between each strings vs the progressive gap that the Stewmac rule gives you. Or you can do consistent centers to the strings. I have definitely found measuring the nut with calipers to work a lot better than the stewmac rule and don't use the rule anymore. I wanted some additional functionality…

I have a customer with a guitar that has an intonation issue. It plays flat at the first and second fret on the D and G string. The factory spec says its a 25.5 scale but I measure from the nut to the 12th fret 12 5/8. I plugged the number for a 25.25 scale into the Stew Mac fret board calculator and the measurement is off from the nut to the first fret. Unfortunately I now longer have the guitar in my possession so I cant tell you exac…

I did a pretty big update to my web tools last week. These are updated from the older versions I had up on celestialinstruments.com. There’s an updated FFT tool now, plus mode detection for guitars and plates, wolf note detection, played-note energy transfer, monopole mobility, plate thickness calculation, and 1/2/3/4 DOF modeling that can be prefilled from FFT data. The part I’m most excited about is being able to fit a measured guitar re…

Hey folks, I put together a video showing how I measure the long, cross, and transverse frequencies on guitar top plates before thicknessing, following the Gore method. I also walk through using the calculator I built (based on Trevor Gore’s equations) to get target thickness and track density / young's modulus. Fair warning: the video’s a bit YouTube-y in tone thumbnail faces, a little energy for the algorithm, but the content is genuine…

I've been testing all my top and bracewood to find the best combination of stiffness and density, optimize plate thickness, etc. I started with Nicoletti's spreadsheet which calculates both stiffness and density, but since I was also testing deflection, I decided to compare the flexural modulus using that method (with the formula from T. Gore's book) on the same plates and bracewood. Unfortunately, I'm having trouble getting a satisfa…

Initial frequency analysis of this D28 copy (done with a temporary 35g bolt-on bridge and the back plate taped on) is VERY LOW. Main air resonance 83.5hz and top monopole 156.6. It's standard Martin scalloped X-bracing with a torrefied Adirondack top. Since I can still easily access the bracing, I'm thinking of going in and laminating wood on top of the X brace to stiffen it. Other options would be a very light bridge, though I'm not…

For folks familiar with the Gore / Gilet books and the top thickness calculations in section 4.5. I made a web based calculator to do the nasty spreadsheet math... So this is for once you've weighed and measured your top plates and then found the long, cross and transverse resonances it gives you the target thickness to hit a particular frequency for the long resonance of the plate. Just sharing so folks don't have to do the math for bu…