The Dependence of Stringed Instrument on its Ribs

There are three essential parts in a violin: the scroll, the neck, and the plates; the back and the top; and the ribs. On its core, however, it’s on its ribs that the instrument relies upon, particularly on the instrument’s curved sides. With a thickness of only 1 millimeter to support the torque of the bow and strings, it stands proudly between the back and the top.

We can also find some handmade fiddles that have ribs taken out from a hunk of hardwood as a single piece. Of course, we can always see that the traditional ribs are bent. Bending involves heating the wood. Bending a hardwood takes time to master. You would probably break a few maples before you get it right.

Bending the wood by heat can be done in a lot of ways. You can use a cauldron full of boiling water, wrapping the form with NASA heat blankets, a spring-loaded mould, and a steam box, or anything that you can imagine or dream of. But with all these methods, the older method works similarly to others. Metals like the aluminum, iron pipe, bronze or a copper saucepan with rounded edges are suitable for heating. The metal should be formed in curves similar to the C bouts of the instrument. The rib must be forced around the metal until the desired shape is formed.

The heat of the iron must be intense that when you drop water onto it, it does not flash to steam; instead, you can see popping droplets bounces off.

Creating a Form

How does a violin maker determine the kind of shape they want? The answer is by creating a form. According to violin maker Christopher Jacoby, he is using inside forms, which would mean bending the ribs against and around the outer shape. There are also those who use inside forms which are done by pressing the ribs into the structure.

Jacoby would start by drawing the shape.  He could invent his own shape or copy one of those created by Cremonese Golden Period masters. The outline of the forms is often taken from the back part of the instrument. It was an ideal part because, after many years of playing and repairing, it remained less distorted and worn compared to the softwood top. When drawing a violin, you start first with the corners then you pull the C bouts in between them, followed by the broad hips of the lower and upper bouts.

On the violin’s shape would be determined by the form of the ribs when it is finished. Many years have passed, a lot of instruments and others comfortably relying on the shoulders of great works, a maker can begin in geometrical patterns and in that particular form would he or she build the instrument. But to start with, each maker would try to imitate a great instrument that they admire the most. The way to create this great instrument is to look for the way it is bent. So the building would start around the ribs as the top and back are glued to it. Therefore, through the making process, the form should be drawn backward.

If you look at your violin, cello, or viola, you can see on most of them that the distance from the ribs to the top of spruce on the rounded edge and the maple back is even. Sometimes bases do not have an overhang (the rib’s distance to your top back plate’s side), but you can see that on most bowed string instruments. Having a protrusion is also essential for your plate edge, because baby brothers, Labrador retrievers, and patches of ice happen. The ribs and other delicate parts of the instrument can be protected from disaster and impact if you have an overhanging edge. More or less, the rib’s distance from the back part outline all the way around it (though styles would often vary) must be at the right proportion.

You will pass the purfling when you go towards the finished form coming from the back outline. The purfling is a beautiful string line around the back and top of the instrument. Aside from its very decorative appearance, its functionality is similar to the overhang which you can find on edge built to make the instrument last long.

In a majority of cases, the purfling is made out of three strips of wood: white/brown/black. It was then scored with a very sharp knife inlaying it into the curved channel you can find around the perimeter of the violin. Then, with the use of tiny chisels, they are hallowed out. So why do violin makers bother to do this? Because when your baby brother or a Labrador suddenly drop your violin by mistake onto its edge overhang, it would most likely crack. But the crack will not travel up to the plate because of the three-strip purfling in the trench around the edge.

Jacoby said that when he makes a form, he will use the violin’s back outline. He would trace from the inner black part of its purfling inside, all the way around, and then start planning for his blocks. The purpose of the blocks is to stand between the back and top part of the spruce and willow, serving as their vertical towers. After which the bent ribs are glued on the blocks after they are being carved to the shape of the desired form. Then, violin makers would set the blocks into the structure and would bend the fragile ribs around them as they are being glued to make the desired outline come out.

How to Bend the Ribs

For the actual bending process, the material that is good for the violin’s rib is the maple. Lightness and thickness is the best characteristic of the maple which is essential for carving. It can be carved down to the thinnest level where its resistance to pressure is not yet compromised. Softer hardwoods are essential for viola and cello, using it for good effect. However, Maples seem to be the best for violins and can rarely be seen on anything.

Violin makers would use an electric bending iron to pull dampened ribs around its shape with intense pressure. They make sure that the metal is scorching that even dropping water onto it would bounce off rather than flash to steam. As the rib bends, a curved caul or a strap is wrapped around it to reduce breakage and help to even out the pressure.  Jacoby uses flexible leather, although he also considers metal flashing and other materials that are also good. When heat and pressure are applied to the maple, its lignin softens, allowing the maker to create whatever form and blocks they can imagine out from 1-millimeter-thick ribs by changing its shape.

Getting such a straight-forward step right is a learning process according to Jacoby. The ribs will crack and split if the heat is not hot enough, so it’s just useless. If you apply too much heat, even though the wood may bend yet, it will char, leaving ugly black scorching marks on the violin’ side. So when it comes to bending ribs, the heat must be just right, like the porridge of the baby bear.

This is what violin makers do. Of course, they had been to a lot of practicing, turning a few pieces of maples into kindling.  Therefore they can be able to determine the right amount of thickness needed for a particular set of ribs. So they can bend and glue for a few hours on the blocks of their desired form. Any onlooker would never think that a violin maker has spent hours and hours on perfecting the shape of the ribs.