Making a Beautiful Curved Neck ... First Time Build (newbie question)

No worries! I was so glad for the help I got when I started. No point being on here if not helping, exchanging, getting inspired.

I use hardwood (ash) which is just the hardwood we get at our hardware outlets. What we have here in Oz is 42mm x 19mm. No matter what hardwood you get, look for quarter-sawn lengths. That means when you look at the end of the piece, the grain runs vertically. It's much stronger that way. Or some people glue three thinner pieces together side-by-side, in which case it doesn't matter if the lengths aren't quarter-sawn because laminating adds a lot of strength.

For fingerboards I use rosewood which I can get quite cheap here. It is 10mm thick. That's quite thick for a fingerboard but it adds a LOT of strength when glued onto the neck. I've also used a 9mm thick of the same timber as the neck, and I've used decorative molded skirting which isn't very stiff but once coated with a thick layer of 2-part epoxy is pretty solid.

The reason I mention the fingerboard and neck strength is because it will dictate how much wood you can take off the back before you end up with something more like a bow and arrow set.

Once I've got my fingerboard on and my neck width right (on a 4-string I go 38mm which gives 10mm spacing and 4mm on the sides), I mark off where I want the shaping to finish so I keep a nice square profile where the neck goes into the box. Same at head end so the shape doesn't mess with the wings. Then I draw a line right down the middle of the back of the neck and one about 7mm each side. These are visual guides. Then I go crazy on it with a rasp. (Remember this is starting with a neck that is now 19+10 = 29mm thick.)

At each step I'm doing both sides so I'll get it pretty symmetrical. The first pass along each side I'm at maybe a 30 degree angle. In any case, I end up with a flat-ish plane that goes from my 7mm guide line to about 1/3 or 1/4 of the way into the side of the neck. I do a visual to make sure it's roughly uniform.

Then I do another on a steeper angle to take the outer edge of that plane off and down to with maybe 8mm of where the neck meets the fingerboard. Then I round off the flats on a shallow angle and take from that 7mm guide line all the way to the center line and the side edge to within maybe 4mm of the fingerboard. It's starting to look like a neck now and I'm starting to get pretty fussy about it being uniform, although of course it's still pretty rough from the rasp. Run your hand along it on different planes and you'll feel if it gets thicker in places and you can lightly rasp those bulges out. Also you can see dips and bulges from different viewing angles.

Then I rasp a couple of mm out of the back. I just find them a bit chunky at 29mm. 27mm feels surprisingly slimmer. Again I'm checking to see that my flat back is pretty uniform.

Next I round off the edges of the flat back pretty wide, but I try to keep a feeling of an area of relative flatness along the centre. CBG necks can be quite narrow and I like some meat and something comfortable for my thumb to anchor on. I don't want to feel like I'm holding a broomstick. At this point I'm checking a lot, by sight and feel, for uniformity in the neck. No dips, no bulges. It's fine for it to thicken at the high frets a bit, but not at fret 1. I want to be able to play down low without my thumb having to ride over a bulge near the nut.

Then I take a flat file to the whole thing until the rasp marks are gone. I'm careful to not make new flat spots with it. I just keep fluidly changing the angles. It's also a good time to get rid of most of the edge-i-ness on the sides near the fingerboard. And I use a half-round file to scallop the shape where the rounded neck has to transition to the flat headstock and the square part where the neck will go into the box. And any small inconsistencies in the profile can be easily fixed.

Bet that sounds like a lot, but I can shape a neck to this point in about 25 minutes. Then sanding with 60 grit, 120, 240, and 400 and it should be smooth like butta. On the 60 grit, you can get rid of any remaining tool marks and minor inconsistencies in the profile. If you wrap you hand around the neck and sand the whole length for a bit, it will match your hand nicely. The grades after that are really quick to do.

I guess maybe from go to whoa, an hour. Sanding takes most of the time up if you want a really smooth neck.

Hope that helps. Others will no doubt share their methods which will be different but maybe better.

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Glenn Reither May 1, 2012 at 1:44pm

No worries! I was so glad for the help I got when I started. No point being on here if not helping, exchanging, getting inspired.

I use hardwood (ash) which is just the hardwood we get at our hardware outlets. What we have here in Oz is 42mm x 19mm. No matter what hardwood you get, look for quarter-sawn lengths. That means when you look at the end of the piece, the grain runs vertically. It's much stronger that way. Or some people glue three thinner pieces together side-by-side, in which case it doesn't matter if the lengths aren't quarter-sawn because laminating adds a lot of strength.

For fingerboards I use rosewood which I can get quite cheap here. It is 10mm thick. That's quite thick for a fingerboard but it adds a LOT of strength when glued onto the neck. I've also used a 9mm thick of the same timber as the neck, and I've used decorative molded skirting which isn't very stiff but once coated with a thick layer of 2-part epoxy is pretty solid.

The reason I mention the fingerboard and neck strength is because it will dictate how much wood you can take off the back before you end up with something more like a bow and arrow set.

Once I've got my fingerboard on and my neck width right (on a 4-string I go 38mm which gives 10mm spacing and 4mm on the sides), I mark off where I want the shaping to finish so I keep a nice square profile where the neck goes into the box. Same at head end so the shape doesn't mess with the wings. Then I draw a line right down the middle of the back of the neck and one about 7mm each side. These are visual guides. Then I go crazy on it with a rasp. (Remember this is starting with a neck that is now 19+10 = 29mm thick.)

At each step I'm doing both sides so I'll get it pretty symmetrical. The first pass along each side I'm at maybe a 30 degree angle. In any case, I end up with a flat-ish plane that goes from my 7mm guide line to about 1/3 or 1/4 of the way into the side of the neck. I do a visual to make sure it's roughly uniform.

Then I do another on a steeper angle to take the outer edge of that plane off and down to with maybe 8mm of where the neck meets the fingerboard. Then I round off the flats on a shallow angle and take from that 7mm guide line all the way to the center line and the side edge to within maybe 4mm of the fingerboard. It's starting to look like a neck now and I'm starting to get pretty fussy about it being uniform, although of course it's still pretty rough from the rasp. Run your hand along it on different planes and you'll feel if it gets thicker in places and you can lightly rasp those bulges out. Also you can see dips and bulges from different viewing angles.

Then I rasp a couple of mm out of the back. I just find them a bit chunky at 29mm. 27mm feels surprisingly slimmer. Again I'm checking to see that my flat back is pretty uniform.

Next I round off the edges of the flat back pretty wide, but I try to keep a feeling of an area of relative flatness along the centre. CBG necks can be quite narrow and I like some meat and something comfortable for my thumb to anchor on. I don't want to feel like I'm holding a broomstick. At this point I'm checking a lot, by sight and feel, for uniformity in the neck. No dips, no bulges. It's fine for it to thicken at the high frets a bit, but not at fret 1. I want to be able to play down low without my thumb having to ride over a bulge near the nut.

Then I take a flat file to the whole thing until the rasp marks are gone. I'm careful to not make new flat spots with it. I just keep fluidly changing the angles. It's also a good time to get rid of most of the edge-i-ness on the sides near the fingerboard. And I use a half-round file to scallop the shape where the rounded neck has to transition to the flat headstock and the square part where the neck will go into the box. And any small inconsistencies in the profile can be easily fixed.

Bet that sounds like a lot, but I can shape a neck to this point in about 25 minutes. Then sanding with 60 grit, 120, 240, and 400 and it should be smooth like butta. On the 60 grit, you can get rid of any remaining tool marks and minor inconsistencies in the profile. If you wrap you hand around the neck and sand the whole length for a bit, it will match your hand nicely. The grades after that are really quick to do.

I guess maybe from go to whoa, an hour. Sanding takes most of the time up if you want a really smooth neck.

Hope that helps. Others will no doubt share their methods which will be different but maybe better.

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Build a Cigar Box Guitar 101

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