So there I was, sound asleep when I had one of those thoughts that wake you up in the middle of the night. I had one of those around 5:00am this morning. It was one of those moments where I initially thought that I messed up big time. If you have been following my blog, you have seen me bracing up the top and getting everything ready for the big top/back/side glue up. If you are a careful observer, you will have noticed that I skipped a very important step. I will tell those 'not so careful observers' what I missed that woke me up out of a dead sleep at the end of this posting.
I spent some time cleaning up the edges of the sides so the top and back fit correctly, and finish sanding all the bracing. Oh, I also checked the sharpness of my 1/4" chisel. My finger can attest to the fact that it is sharp. Once that was all ready and the bleeding stopped, I set up my go-bar deck for clamping the back to the sides. I glued it all up, and clamped it all in place. I really like using a go-bar system for all of this clamping . It really speeds things up, and I feel like I am getting good even pressure over the entire gluing surface. One thing I did was to make thin caul to go around the edge of the guitar to protect the back from the go-bars. They will dent the wood pretty easily and I don't want to have to steam out all of those little divots. Basically all I did was cut a piece of masonite the shape of an oversized guitar with the center cut out. It works well and is flexible so it conforms to the radius.
Okay, now for the answer. I glued all the braces on the top and forgot to cut out the soundhole. "No big deal, just cut it out" you say. Well that sounds good until you realize that the braces keep it from sitting flat, and it also keeps you from using a circle cutter on the inside surface. After a bit of thinking about how I was going to tackle this, I came up with a simple solution. I screwed a small block of MDF to my workbench the same height as the cross braces. I drilled a small hole in the center of this block the size as the pin in my circle cutter. Then I clamped the top over this block with the hole centered to the hole that was in the top from the rosette cutter. I put spacers under the edges of the top and so I could clamp it tight. Then I cut it out. It worked perfectly! Another minor thing I overlooked was drilling out the top brace for the truss rod adjustment access. It was easily fixed with a long drill bit. This is one of those things I didn't need to do on my dreadnaught as the adjustment hole for the truss rod was below the braces.
Here are some pictures:
It worked perfectly. You can see the little block with a hole in it for the circle cutter. This fits neatly inside the cross brace and sound hole braces allowing the top to sit above the table.
All clamped up and ready to be cut. The top is very securely clamped to the workbench so there is no chance of it moving.
The back all glued on and go-bar'd in place. I added a couple of cross clamps too for 2 places that didn't have the glue squeeze out that I wanted to see.