I've started the long and laborious process to close the soundbox (ie. attach the back). Actually compared to the bracing or the rosette, it's not that bad. Before you can close the soundbox though, there a few very important steps you can't forget - namely bracing the back. I'm missing some good pictures, so I will update this post later.
You saw me route and glue the back strip in a previous post, now it's time to work on the inside surface of the back. First you start with the center seam reinforcement brace. This brace is thin but wide and you want to make sure that the grain runs vertically in the cross-section. Once you've cut the brace (remember to watch your fingers! I had a few close calls and it pays to invest in a Saw Stop table saw...) it's time to glue it and clamp it like any other brace. The back should be braced in a radius dish so a go-bar clamping system works best for this step.
Once the seam brace is secured, you'll want to round out the profile. I found a micro chisel (I use Flexcut hand chisels) and sanding blocks do the job most effeciently. Once it's rounded and smoothed you can mark the places for the back cross braces (typically three) and use a modeler's saw and more micro chisels to remove sections of the seam brace for the cross braces. Similar to how the soundboard braces were prepared, cut and and then shape the cross braces using sandpaper attached to your radius dish. Then you can glue and clamp them into place. Now it's time to finish shaping the profile of the cross braces to prepare it for attaching to the soundbox. One final step for the back is to trim off the excess seam brace from the top and bottom so that it will fit snuggly between the head and tail blocks already on the soundbox. You can see me doing this below.
You saw me route and glue the back strip in a previous post, now it's time to work on the inside surface of the back. First you start with the center seam reinforcement brace. This brace is thin but wide and you want to make sure that the grain runs vertically in the cross-section. Once you've cut the brace (remember to watch your fingers! I had a few close calls and it pays to invest in a Saw Stop table saw...) it's time to glue it and clamp it like any other brace. The back should be braced in a radius dish so a go-bar clamping system works best for this step.
Once the seam brace is secured, you'll want to round out the profile. I found a micro chisel (I use Flexcut hand chisels) and sanding blocks do the job most effeciently. Once it's rounded and smoothed you can mark the places for the back cross braces (typically three) and use a modeler's saw and more micro chisels to remove sections of the seam brace for the cross braces. Similar to how the soundboard braces were prepared, cut and and then shape the cross braces using sandpaper attached to your radius dish. Then you can glue and clamp them into place. Now it's time to finish shaping the profile of the cross braces to prepare it for attaching to the soundbox. One final step for the back is to trim off the excess seam brace from the top and bottom so that it will fit snuggly between the head and tail blocks already on the soundbox. You can see me doing this below.
