Four Part Harmony

Wow, it seems I’ve been making a decent amount of progress on the guitar project recently. I’d better get a quick update in here, as I’m starting to get behind. I actually took many of these pictures last week, and I’m kind of playing catch up here, so I’ll have to be brief.

I was able to get the heel and tail blocks all glued up last week. This was a big step. I thought I had a problem, as I ended up with some small gaps at each end, but everything will be covered, and everything stayed square and centered. I was worried at first, but hindsight says everything is a-ok.

With the blocks glued in, I was able to start shaping the sides. I used a small hand plane to take everything down close to the final thickness, then sanded everything in the radiused dishes to arrive at the final dimensions. I think I’ve mentioned before, but the top and back of the guitar aren’t flat. The back is formed to a 20-foot radius, and the top is shaped to a 28-foot radius. This work took some time, but planing is fun. I had a big pile of fine rosewood shavings when I was done.

And here’s the guitar sitting in one of the dishes, with the rough contouring all finished up. I sanded both sides in the dishes until the radius was uniform around the entire perimeter of the guitar. Then I started in gluing up the kerfing. the kerfing is a strip of wood that forms to the contour of the top and back, and provides the bulk of the surface that the top and back are glued to. To glue it on, I needed to make a bunch of these high-tech clamps, which consist of clothespins with rubber bands wrapped around them. I had Nicki help make them one night while we were watching a movie.

Here’s the top kerfing all glued and clamped up. I then did the same thing for the back.

Here’s a shot of the sides with all the kerfing installed. I also had to install some thin spruce braces along the sides. It’s almost ready to be joined with the back. First I had to deal with the end wedge.

Here’s a shot of me mid-way through chiseling out a slot for the end wedge. I had a piece of plastic, and some plastic bindings that I had originally ordered for this purpose, but it just looked funny. I couldn’t bring myself to do it, so I got some wood bindings and a small piece of koa veneer, which I cut the end wedge from.

Here’s a blurry picture of the koa and two thin strips of purfling that will be the end wedge. It was a lot harder to get this to fit tightly than I thought it would be. I spent a few hours, over two or three separate trips to the shop to get the fit tight enough to glue in. Then once the glue had dried, I had quite a bit of scraping to do to bring the wedge and binding down flush. This took a few more hours. I thought this was going to be a quick and easy step.

Here’s the finished product. I think it came out pretty nice, and I’m very glad I decided to scrap the plastic bindings.

With the wedge installed, the back and sides were ready to be glued up. I was pretty nervous, and it took me a while to actually get up the nerve to do it. I had to rout some shallow channels for the back braces to sit in, so the back would sit flush with the sides.

After a fair amount of trial and error, and a dry run, I glued everything up and hoped for the best. This was at 12:30 last night. I snapped a few of the wooden dowels that I’m using for clamping bars, so I was worried that I didn’t have enough clamping pressure at the back end. There wasn’t much I could do though, so I pretty much crossed my fingers and went to bed.

Here’s how it came out though. Everything looks pretty good!

Here’s another view.

I’ve also been working on the neck…but that will have to be covered later. So long for now.