I tried a search of this forum but didn't come up with hits that addressed what I'm talking about.
I'm new to CGB building and have spend a number of evening bouncing around the internet looking at building instructions and videos.
I hit a video a few days ago that talks about cutting a 3 degree taper on the top side of the portion of the neck that is inside the box. This will cause the neck to angle downward (from box to head).
According to the video, this is done to address bending of the neck under string pressure and help keep the action height constant across the length of the fret board.
Is anyone familiar with this technique? Is 3 degrees the default standard?
I give all my builds at least a 3 degree back angle to improve playability, most commercial guitars also have this back angle.
3 degrees is not a standard but seems to be the best compromise. Lutes tend to have a more extreme angle.
I built a two string gourd bass with a 12 degree back angle to compensate for the high bridge.
Thanks for a quick response Robert. This site is proving invaluable in adding to my limited knowledge base. You use of a 3 degree neck angle is good enough for me.
Are you not thinking of the extreme headstock angle on a lute ?
Seems legit. Some here have even put on necks with adjustable angles. The exception is for fretless instruments where the height of the strings doesn't matter. All a balancing act between the string tension pushing the bridge down and the height of the strings over the fretboard. Then again the main rule of cigar box guitars is there are no rules and of the rules it doesn't have a 3 degree angle sounds like a very good one.
pitched necks and tall bridges are great!
warning: once you start you'll never go back.
Why? a greater percentage of the string tension is directed downward into the box. = much more volume. Take a look at a violin.
some years ago i worked out a easy way to do it with a scarf join on a bandsaw, see here http://handmademusicclubhouse.com/photo/thetinyguitarsbodyendscarfj...
3 degrees is sod all, i don't measure, i just rule a line and cut, but its more like 7-10 for sure. enjoy
I really appreciate your inclusion of the link to the photo. So, you cut the angle you want out of the top section of the neck where it passes thorough the box, then glue it on the bottom so the two sections remain parallel to one another, but the neck above the box is tilted down..........
Wow, you just blew my mind.
Of course, you have earned the right to blow my mind with your "I See Threes" lesson in the basics of music theory.
That scarf joint inside the box, to angle the neck, is such an elegant solution to alter the string tension on the box lid.
On my ukes with CB Gitty concert necks & fretboards, I attach then to the box with a hanger bolt after I cut anywhere from 1 to 3 degree down angle to the heal. Most of the time it's 1 to 1.5 degrees. 3 degrees if huge. Remember - trucks have to use low gear on 6 degree down grades. Even at 1 degree, sometime I have to put a tooth pick under the bottom of the heal, because the strings hits the 12th fret.
I actually drew out all of this to see what it looked like full scale.
With a 25" scale and a 1/4" fret board flush with the top of the box, I need a bridge 1/2" tall to keep the strings a constant distance from the fret board from nut to the end of the fret board. That is, of course before any bending of the neck under string pressure. That would lead to use of shorter bridge to keep strings parallel.
I'm a ways from construction of a new neck, but gathering this type of information is useful.
Thanks for your help.
That's my thinking.......
This is a little off subject , but I always put the bottom of a 1/4" fret board flush with the box, so the top of the fret board is a 1/4" above the box . That moves the strings further away from the box and makes it easier to pick with out hitting the box .