Back Prep

The first photo below shows the attachment of the back strip. The back strip is a very thin piece of wood (maybe 1/16″) and maybe 5/8″ wide with the grain running laterally (rather than longitudinally which would be much easier to rip) which is used to reinforce the glue joint on the back, historically one of the weakest joints on the guitar. The second photo below shows my logo branded into the back strip. I use a brand I bought from Rockler which is low-tech by today’s standards (I can’t justify a laser, at least not yet) but works really well. It makes me nervous every time I do it, however, like bending sides.

gluing on the back strip branding

The first photo below shows your’s truly cutting out braces from rough stock.  I use either Sitka spruce or mahogany for the back braces and usually use Sitka for dreadnoughts to keep with tradition.  I use 1/4″ bracing exclusively now rather than a more common (at least among factories) 3/8″ wide.  Martin has taken to offering 1/4″ bracing on some of their guitars, I think several of their “vintage” models.  1/4″ is a little harder to work with but it’s used for a good reason.  By narrowing the brace 33% and increasing its height  by a few percent, as any engineer can tell you one ends up with the same rigidity with significantly less mass.  Mass is the enemy of sound (on the soundboard and back, that is, not necessarily elsewhere–sustain is often improved by mass in other areas).

cutting back braces shaping for the back radius Go-Bar Deck

The second photo above is me shaping the backs of the braces to the back’s 12 foot radius.  I use a template to trace the radius on the brace then use the belt sander to remove the stock to the line with a final sanding on the sanding dish.  This gives the back tremendous strength for its weight.

I use a razor and a chisel to cut slots in the back strip to accomodate the braces.  I just think it’s easier than cutting relief into the brace itself and, as any of you following this blog so far might have sensed I try to take the easy way out whenever I can.  I’ve used the bandsaw to pre-cut the “ramps” on the braces but will use a chisel to do their final shaping.  I try to use power tools to remove as much stock as possible during production.  While purists will scoff at this I do it for several reasons:

  • It reduces tedium.  I have a short attention span and removing stock is boring.
  • It improves quality.  If I’m bored I’m more likely to make a mistake.
  • It improves consistency.  Using machines and jigs makes following specifications much easier.
  • It improves safety.  Boredom equals complacency which increases the likelihood of me doing something stupid and getting injured.
  • It improves health.  Much of stock removal, especially when shaping necks, can be physically hard on the builder.  Carpal tunnel syndrome and repetitive stress injuries are greatly reduced by the judicious use of power tools. 

Years ago as a carpenter I developed the philosophy of using the right tool for the right job and I try to do the same in my shop. 

I want to make the point here that I don’t believe that my approach to building is the only one or even the best, while I think it is the best for me.  We are in what many have called the “Golden Era of Lutherie” and there are many builders out there building guitars with different approaches and different philosophies of building and each has validity.  While the dimensions and basic design of a guitar are pretty similar from one builder to the next, the final products are amazingly different in their smell, sound, playability and overall feel.  So much of the personality of the builder insinuates itself into the product.  There’s more than one way to skin a cat.

 I use a Go-Bar deck to glue the braces on. The Go-Bar deck is a really handy tool for the small shop.  It’s fast, easy to set up and allows for the distribution of pressure over a wide area. 

All that’s left for the back now is to shape the braces using a tiny block plane, finish the scallops with a really sharp chisel and sand.

1 Response to “Back Prep”

  1. 1 Harry Moore

    It’s looking good, Seth! Thanks to you and others who are donating to this year’s scholarship fund, we have awarded five scholarships. Your generosity is greatly appreciated – and someone is going to wind up with a GREAT guitar, to boot!


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