Newark School of Violin Making
RAB Awards 2016, 2017
Education Services Award 2017
Michael was awarded the equipment to begin acoustic analysis and a day at J & A Beare to discuss acoustics with Andrea Ortona and get feedback on a couple of his instruments. He writes:
I bought a measurement microphone and USB interface with the award. I will also purchase software once I have a better understanding of the analysis and the available products.
I have obtained spectra of modes I, II and V of my 4th violin and checked them to tap tones, altered the modes to match standard target frequencies and seen the associated changes to the spectra. I investigated the change to the spectra during f-hole cutting, fluting and bass bar fitting. I am getting a much better feel for relative impact of these actions on the free plates. I have also looked at the higher-frequency changes during these actions. Given the understood limitations of any free-plate analysis my next step is to build a rig for complete instruments. I also plan to improve my method of impact so I can factor the amplitude of response by impact force and therefore compare my readings to other violins.
My day at J & A Beare was a great experience. Mark Robinson gave feedback on my making, looking at many details such as golden period purfling and fluting and antiquing. Andrea discussed the acoustic analyses he has carried out over past decades and we looked at what I have done to date and where to go in the future. We discussed a project to measure instrument stiffnesses which we have been developing since then. I also had time to look over and make notes on some beautiful instruments. Many thanks to everyone at J & A Beare and RAB Trust!”
Michael was awarded work experience with the restorer Paul Gosling, which he undertook in summer 2017, just after finishing his studies at Newark School of Violin Making. He sent this report:
We started the placement by sitting down together to observe and discuss the instrument. As I was to find out during my time with Paul, there is so much to learn before a tool is even lifted. The instrument is an early 20th century German trade instrument with some uncommonly nice features including nice flow in the lines of the scroll and outline and a warm clear honey coloured varnish.
There were numerous cracks in the peg box and front plate to clean and repair. It is fascinating to see how a restorer slowly and methodically weighs up different methods, materials and sequences. With many options at his disposal, it takes time and consideration to arrive at a plan of action. I learnt to really savour this time.
The instrument required a neck graft. Preparing the top block for a new mortise was an enjoyable job of wood working. Firstly the existing neck is sawn out, close to the button and ribs for efficiency. Next the horizontal split of the neck root is exploited to remove the remaining wood. The edges are left to the end when they are carefully removed from the rib and block. The wood above the bottom is slowly sliced away until just above the glue-line. The remaining fibres are wet and lifted off with an opening knife. Finally all the internal surfaces are worked completely flat, checked with a small straight edge. Working accurately here means the next task is a very satisfying short task with a block plane, shaping a willow insert to a perfect fit. Once glued, taking care to glue size rib end-grain, this insert is shaped to the curve of the ribs, ready for the new mortise.
There are multiple cracks in the peg box extending from peg holes. Due to the orientation of their fibres, spiral bushings are significantly better at crack arresting than solid bushings. For these repairs I made single-wall spiral bushings for the first time. They benefit from allowing greater control and remove the chance of unequal mandrel pressure between walls. They also have some difficulties: they are more delicate, the mandrel sticks to them easily, there is less tolerance for push-through and the smaller bushing can get in the way of the mandrel when fitting the larger bushing. There are several details critical to get these to work. The shaving should be around 0.15mm thick and around 12mm wide with ends skew cut. At first I had a wider shaving and it was too untidy and grabbed the mandrel too readily. The length of the small hole bushing was 7cm and the large hole 9cm. The final key point is that the mandrel is really hot before using. I left it in a water bath at about 80 degrees. After several practices this technique produced very neat and tight bushings time after time. I finished the bushing with a solid box bushing.
In all of the activities above, and much more, Paul has taught me so much and given me so many technical and professional insights from his wealth of experience. My time at his workshop and home was a huge pleasure for which I am very grateful to him, his family and the RAB Trust for making possible.’