I used a special wooden "corner" of sorts that goes over the edge of the workbench today. It is actually clamped to the workbench so it doesn't move. The mold is put either on top of the wooden corner, or on the side of it when cutting the blocks. I used gouges that are sharp on the inside edges to cut off the areas of the blocks where the ribs will be attached. I only did the two inside C-bout corners to start with.
Once again, this is very exacting work. The blocks have to remain perfectly square when you cut the curves for the ribs. I used a small square over and over again to check for squareness. Sometimes I worked on top of the wooden corner, and sometimes I worked on the sides of it. I had to keep flipping the mold over to make sure I was cutting evenly from both sides and didn't go through any of my lines.
The ribs are cut from larger pieces of rib stock. This is heavily flamed maple. If you want the fiddle to look really beautiful, then it is important to cut the ribs and back from the same piece of wood. This makes all the flames match in size and intensity. Once the ribs have been cut, they have to be measured for correct height and thickness, and then ultimately for correct length based on where they will be placed on the fiddle. To get the thickness accurate all over, I used a special caliper that I slid the wood through. When the gauge showed an area that was too thick, I marked that area with a pencil. Then I used a rough rasp to remove the pencil markings. I did this over and over again until the ribs were fairly uniform in thickness. I used sandpaper to smooth out the rasp marks.
The edges of the ribs were planed so that they would be level, square, and the correct height. Once again, I used the wooden corner (and Greg) to help.
Next, we measured the area where the rib would be bent and glued, and marked and cut the rib to the correct length. The rib will be cut slightly long.
Now, it's finally time to bend the ribs! I used an old piece of rib material to practice with first. Everything went good, so then it was on to the real thing! I used a bending iron, bending strap and a small block of wood to help bend the rib to fit the C bout. This is the toughest one to make because it has the sharpest curves out of all the ribs. Highly flamed maple is also hard to bend because the wood tends to break at the flaming. I put the first rib into a bucket of water for a few seconds, and then I used the bending strap and iron to bend it. I had the mold right beside me so I could fit the rib into the area in which it would be glued to make sure it fit correctly and tightly.
That's an overhead view of the rib, bending iron and bending strap, so you have to look closely to see there's a rib in there!
When the rib looked to be bent correctly, we did a "dry" clamp of the rib to make sure there were no gaps that would require me to keep working at getting the rib bent correctly. I used a special clamp that Greg made called a step clamp. It is really neat because it can be resized and used for both violins and violas. You'll see how it works in the next couple of pictures.
Before gluing the ribs to the blocks, wax is put on the edges of the mold where the ribs will be touching. This is just to keep the ribs from sticking to the mold in case a little glue gets in between the ribs and the edge of the mold. The only place the ribs are glued is where they attach to the blocks. They hold their shape because the step clamp puts pressure on them until the glue dries. Violin making uses granular hide glue that is melted in a pot because of its superior strength and bonding with wood. It is actually stronger than wood glues and other specialty glues, and it will release under heat so that repairs can be made later on without damaging the wood of the instrument. It is not okay to use liquid hide glue that comes in a bottle for construction and repair work because what is added to the glue to keep it in a liquid state in the bottle weakens the glue and it won't hold under pressure.
After sitting overnight, I removed the clamps and here is what it looks like!