Trade Secrets!

Banjo Killer? The scoop on forward X bracing for greater guitar volume.

Issue 51 December 27, 2007

Photo: shaving
ow I make a Banjo Killer with forward X bracing
Banjos are loud! I build them, and I love to play them, but in a bluegrass band their volume is tough for a guitar to compete with. That's why I build my Sams Guitars to be Banjo Killers: using forward X bracing to make them louder. Here’s the story:

In mid-1938 Martin relocated their X braces, moving them back away from the soundhole by about half an inch. This reduced problems with warping behind the bridge, because it stiffened the top — but it lowered the volume of the guitars.

Many builders today, myself included, prefer the original “forward” X bracing. I recommend it for players who will be playing in a group. Here’s how to lay out forward X bracing on our Dreadnought Guitar Kit.

Illustration: forward X bracing
The “popsicle stick” brace wasn’t used in the early 1930s, and isn’t used here.
Illustration: luthier cartoon

The gray areas at left show typical modern bracing, and the white shows the forward X bracing. The center of the X joint moves closer to the soundhole, but you can see that it’s not as simple as just sliding everything forward 1/2".
Bridge plate stock
Illustration: forward X bracing

Illustration: forward X bracing

The X braces are at a slightly different angle, changing from 98° to 100°.

The gap between the soundhole to the front edge of the X joint, (not the centerpoint of the joint) becomes 1".

Shaped braces

Sitka spruce soundboards

Photo: shaving
ow to do it:
1. Make a mark on the centerline 1" below the soundhole.
2. From this mark, draw lines at a 50° angle into the lower body bout areas. With a straightedge, extend these lines onto the upper body. (The two lines at 50° angles to the left and right of center create the 100° X angle.
3. Add a parallel line 5/16" below each line. Your X braces are glued in the 5/16" space between these parallel lines.
4. The four small “finger” braces will keep their relationship to the X braces, just moving forward along with them by 1/2".
Photo: guitar kits We manufacture our Guitar Kits right here in our own shop, so the parts are top quality and everything fits.

Dan Erlewine and I made a how-to-build DVD that comes with the kit.

Photo: guitar kit

Illustration: forward X bracing
5. The two long tone bars still tuck into the X brace at the same location as before, but now they run toward the bass side at a 120° angle.

The shoulder brace above the soundhole stays in the same location.

Behlen ground hide glue
The bridge plate stays in the same place, but it becomes a little longer to meet the wider X brace angle. The flat “popsicle” brace is not used on the forward X braced guitars.
Photo: gluing with a go-bar deck
Here, the X braces and bridge plate are glued up and braced on my go-bar deck. For this photo, I marked the typical brace positions in black, and my forward positioning in red.

Todd Sams signature

Go-bar clamping system

Problem-solving products mentioned above:
Photo: Guitar Brace Chisel Photo: Shaped Dreadnought Brace Sets Photo: Precision Straightedges
Guitar Brace Chisel
Shaped to fit the curves needed for scalloped braces and tone bars with feathered ends.
Shaped Dreadnought Brace Sets
Shaped and sanded to save you hours of work, these complete sets of braces are sized for a dreadnought guitar.
Precision Straightedges
Super accurate straightedges for precise fretting and neck work.
Buy Now
Buy Now
Buy Now
Photo: Behlen Ground Hide Glue Photo: Go-bar Clamping System Photo: Dreadnought Soundboards
Behlen Ground Hide Glue
Traditional luthier's glue.
Go-bar Clamping System
Fast, efficient clamping for braces, tops and backs.
Sitka Soundboard
For your Dreadnought or smaller sized steel-string building projects.
Buy Now
Buy Now
Buy Now

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