Now I have come so far with the batch that I can start completing GammelGurorna one by one. First out is the harp guitar.
I mounted the brass rod between the neck and bottom block on the way to glue back the bottom, but I stopped. My experience of connecting the two blocks with a rod is not good. The few times I tested when I started renovating guitars once upon a time, I ended up removing the rod. With the rod, the sound did not get good and got much better when I removed it.
After a conversation with the customer, I removed the brass rod. In order not to lose durability in the lightly built harp guitar, I instead mounted two round bars between the neck block and the rim to stiffen up the upper part of the guitar top. The string pulls to rotate the neck block towards the sound hole, the rods are subjected to compressive force and do not allow the neck block to rotate inwards. The top becomes much stronger at the sound hole and should not be able to be deformed by the 10 strings.
To be able to press down the last frets with a clamp, I made an abutment for the complicated upper part of the guitar cover. With the bottom off, it's easy to make a small jig.
We'll see how it all works when the guitar is ready, this is the first time I make a flying buttress, but there are many modern builders who use it. In any case, I am convinced that the top will be much stronger and sounds better than with the original brass rod. The entire top below the sound hole, which provides most of the guitar's sound, is now free to vibrate.
I could continue with what I was going to do, to glue the bottom. No major problems as the bottom had not shrunk much. Had to be extra careful to get the "pin", which is an extension of the bottom under the neck heel, in the right place.