First Guitar Build

[Tom Griffin]

This is my first guitar, but not my first stringed instrument having built a cello a few years back. Not sure how much of what I learned from that will apply to building a guitar, but i guess I'll find out. I picked up a back and side set about six years ago because it was too cool to pass up and am finally getting around to the build. They are Brazilian Hickory with some crazy figure and the sound board is Alaskan Sitka Spruce with a bear claw pattern down the middle. I'm just getting started on the project, and thought I would post the progress before getting too far in and updare it as I go. The guitar is a dreadnaught, based on Gen One drawings, but I'll likely deviate from them a bit as I go. So far the plates have been glued up and thicknessed, and I made a radial rosette from wood left over from the back and inlayed it into the soundboard. The mould is complete and I spent the day scraping the sides to final thickness before bending them on the iron that I made for the cello. Next in line will be the head and tail piece blocks and contouring the sides, followed by bracing. It should be an adventure.

[Barry Daniels]

Nice. Feel free to ask questions if you get hung up on something.

[Tom Griffin]

Nice. Feel free to ask questions if you get hung up on something.

Thanks.

Right now I'm trying to decide between a tapered dovetail and a bolted mortice & tenon to join the neck to the head block. I'm sure both methods have their pros and cons.

[Barry Daniels]

A bolt-on has no disadvantages and several real advantages. It’s easier to build and adjust the neck angle. It makes finishing easier. And it makes future adjustments (like a neck reset) MUCH easier. Any tonal benefits to a dovetail iare largely urban myth.

[Alan Carruth]

The only down side to a bolt-on I can think of is the weight of hardware on a lightly built instrument. It seems to make a difference in the sound of Classicals, but on a steel string not so much.

If you're using furniture bolts with cross dowel nuts be sure to put the nuts in the heel vertically with respect to the plane of the fingerboard. I usually drill in from the heel, and cover the hole with the heel cap.

Hardware in a wood structure is always a possible stress riser. If the nuts are put in from the side in the tenon they will tend to cause the heel to split sideways, especially if they are over tightened. One of my students found out about this the hard way when he picked his guitar up off the bench and hit the headstock on a beam in the ceiling. The heel split at the upper of two nuts, and the body simply fell off the neck to the floor. If the cross dowels are vertical, any split will also be vertical, and the sides of the heel will be restrained by the mortice. This is called in the engineering trade 'failing well'.

Also, the drawer of cross dowel nuts at my local hardware store says they are 3/8" in diameter. They're actually 10mm. With the 3/8" drill they're a loose fit, and this makes for more of a stress riser. Get the right size drill.

[Tom Griffin]

The only down side to a bolt-on I can think of is the weight of hardware on a lightly built instrument. It seems to make a difference in the sound of Classicals, but on a steel string not so much.

If you're using furniture bolts with cross dowel nuts be sure to put the nuts in the heel vertically with respect to the plane of the fingerboard. I usually drill in from the heel, and cover the hole with the heel cap.

Hardware in a wood structure is always a possible stress riser. If the nuts are put in from the side in the tenon they will tend to cause the heel to split sideways, especially if they are over tightened. One of my students found out about this the hard way when he picked his guitar up off the bench and hit the headstock on a beam in the ceiling. The heel split at the upper of two nuts, and the body simply fell off the neck to the floor. If the cross dowels are vertical, any split will also be vertical, and the sides of the heel will be restrained by the mortice. This is called in the engineering trade 'failing well'.

Also, the drawer of cross dowel nuts at my local hardware store says they are 3/8" in diameter. They're actually 10mm. With the 3/8" drill they're a loose fit, and this makes for more of a stress riser. Get the right size drill.

That's a good thought installing the barrel nuts vertical instead of horizontal to get them out of the tenon. It might also help to use one long one for both bolts rather than two short ones to spread the force over a larger area. Also, why not drill the hole from the top and hide it under the fingerboard?

[Alan Carruth]

"Also, why not drill the hole from the top and hide it under the fingerboard?"

I've got the truss rod in by then.

[Darrel Friesen]

I drill in a dowel vertically through the heel and then use hanger bolts as per Mario but also a tenon which in my mind, adds thread engagement particularly on the bottom bolt (I believe he used butt joints) and furniture cap nuts for both archtop and flat top guitars. Very solid and have never had a failure although I've only built 30 guitars in the past 20+ years. Seems much simpler as well but I've never tried barrel nuts.

[Alan Carruth]

That's what I do now. Again, the tenon captured in the mortice is your 'safety'; even if the heel splits it can't go anywhere, so you won't drop the box. The tenon need not be a tight fit, but it's also a useful locator.