Vibrating plates

And so we continue...

With the purfling set in I'm moving on to fluting and arching. The fluting is a small hollow which runs round the edge of the plates (top and back) which is the thinnest part of the plate and allows the rest to vibrate.

We're at 3mm at this point and it's quite delicate work, too deep means we run out of purfling depth and not deep enough hampers the vibration of the plate. I have in the past scraped too deep which is very annoying. I'm happy with the look and feel of this one though.

With the lowest point of the fluting established I work down from the top, creating the arching.

The highest point lies around and slightly in front of the bridge position, this will also be the thickest part of the plate. There are many mathematical models of the arching of tops and backs, but I'm not a mathematician or physicist, I'm a craftsperson, so instead I follow the traditional method in which I was taught using templates from old instruments, contours, my eye, aesthetics, my sense of touch and feel for the properties of the wood I'm working with to arrive at a final shape.

The arching has several structural properties which allow it to vibrate which have an effect on the instruments tone and acoustic properties. The long arch, running along it's length, has an important part to play in defining the internal shape and structural strength. The height of this and balance between the upper and lower bouts again have an effect on flexibility and timbre.

I love this part of the process, shaping and getting a feel for how the instrument is going to feel and look. After roughing out all the waste wood you can finally see the detail of what's inside.

For this instrument I'm using an instrument by Guarneri Del Gesu, from 1741 as a model and template. I've made a number of instruments using this model and really like the dark, warm and powerful tones that they have.

There are several modern methods using lasers and mathematical models to arrive at the shapes in which an instrument can be made. I prefer to allow some time and space for artistic interpretation while I continue to learn from the Masters.