Sorry that I didn't get to post the last couple of days, it has been a busy weekend. I got some time to work on the guitar though. I got the back cut to size, sanded and radiused, and the kerfing glued. I ran into a couple of problems with the cutting and radiusing though. I decided to use the method shown in the LMI OM kit journal on Kitguitarbuilder.com using a grid system and tape to get the correct side width. This plan works well, with one caveat. I followed the directions to the letter and ended up with sides that would not radius without sanding a lot of the lower bout sides to get the waist to the correct level. You see, if you measure the plans in the 2" increments as described, you will fail to take into account that the innermost part of the waists will be too short to fit a radius dish correctly. The plans are two dimensional and do not show that the radius raises the closer you get to the center so the waist dimensions need to adjust accordingly. It wasn't a huge deal, but it did throw me into a bit of a worry when I first set my radius board on it to see how much I was going to need to sand. The waist section was almost 1/4" below the radius level which I thought was going to require me to shorten the entire lower and upper bout by that amount to get it to work. Fortunately, that much was not required to be removed and I was able to get it to work. All in all, the lower bout is now 2mm shorter than the plans show and the upper bout is 1.5 mm shorter. It shouldn't be noticeable and the head and tail blocks are exact per plans. I have decided that I will buy the round sandpaper for radius dishes for the next time. It is too easy to make these kinds of mistakes when trying to build a guitar to a radius without the correct tools.
I had one other problem that I believe Ted also ran into. When cutting the tail block, I followed the directions on the DVD only to end up with a block about 1/8" too short. I glued a small piece of mahogany to the end of the block and sanded it to shape. It is almost impossible to see the repair.
Fortunately the kerfing went on without any problems, of course it is almost impossible to mess that up.... [knocks on wood] :)
Here are some pictures:
First I marked out a 2" grid on a piece of cardboard and clamped the sides to it using these little cauls screwed into my workbench.
Here you can see the measurements I took on the plans in the same 2" increments.
I then transposed those measurements to the sides and then connected these marks using blue tape. This makes a nice straight line around the guitar. Unfortunately, the marks around the waist area should have been about 1/4" higher than shown to get it fairly close to the radius.
Here is the microplane rotary attachment on my cordless drill. It makes short work of cutting the sides down to close to the tape. It took me less than 10 minutes to remove all the wood to within 1/8" of the tape.
Here is the guitar after A LOT of sanding to get it to fit inside the radius dish. The 30' dish is under the guitar and the 15' dish is sitting on top of it. This picture might help you understand what I am talking about with the waist area needing to be higher than what the 2 dimensional side drawing on the plans measures out to be.
This is the patch I made on the tail block. It is on the top. Hard to see isn't it! Oh, and yes I know it is not straight in this picture. I was not finished sanding for the radius. Rest assured, it is straight now.
This is the side with my radius board on it to show how I was able to get the waist area to raise to meet the contour of the radius board.
Last but not least, lots of clothespins clamping the back kerfing.
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