Check out some pictures of the assembly of the my Stainer 1679. Now ready for finishing.
A “Violin knife” refers to a traditional tool used in both violin making and in broader luthier and wood working. The basic violin knife is a long relatively narrow piece of tool steel sharpened with an angled ‘blade’ at one end, double beveled and inserted in a removal wooden sleeve handle. What the knife is used for varies on the width of the steel, the angle of the blade portion and the bevel angle.
The blade portion can be made by tempering any high carbon steel, or ready made blades can be purchased from suppliers like Pfeil or Hock. The handles typically are separate and can easily be made in the workshop.
The size of the knife describes the width of the stock. Because the blade can be moved forward in the handle it can have a very long working life, making it an economical tool.
There is a saying in violin making that it takes about only a few years to learn the basics of constructing instruments, but it takes the rest of your life you learn varnishing. A UV Varnish Drying cabinet can speed up the entire finishing process.
Traditional oil varnishes are a combination of drying oil (for example, walnut or linseed), a resin (for example, copal or amber), and a thinner. While initial drying of varnish is accomplished by the evaporation of the thinner, the curing of the varnish is a chemical process; the varnish alters at an molecular level. The curing, or polymerization, of the varnish is accelerated by UV light. Alcohol based varnishes, notably used in the French tradition after the Cremona golden period, do not require this method. Based on my research, I’m certain that the Cremonese makers used oil varnish.
Tanning instruments (both in the white and after coats of varnish) is a common technique in violin making. Exposure to artificial UV light effectively replaces exposure to sunlight. This is useful in areas which have lower sunlight exposure due to winter, or where exposure to direct sunlight isn’t practical (the glass in household windows blocks a large portion of UV light). Aside from curing varnish, sunlight is also used to ‘tan’ an instrument which darkens the flaming of maple.
CAUTION: exposure to UV light causes cataracts and skin cancer, just like over exposure to the sun. The bulbs I recommend below should be fairly safe for short period of exposure, but its best to avoid prolonged exposure.
The UV cabinet is a tool which provides a way to accelerate the exposure of the instrument to UV both for tanning of the bare wood, and accelerating the curing of the varnish between coats. An instrument may be tanned for one or multiple weeks, while varnish exposed to UV will cure overnight.
A simple, cost effective method of building a UV cabinet is the steel can cabinet. Not glamorous :), but certainly low cost and functional. This consists of a galvanized steel rubbish bin or garbage can, with UV florescent lights mounted vertically inside the can. A small amount of electrical expertise is required.
Hand planing is a fast and effective way to achieve a great finish on ribs. Hand planes are also key for getting a good flat surface on plates, necks and the back of finger boards. How well your plane works for you will depend on its setup, including the pitch angle. Check out my new addition to the best practices page, Hand Plane Setup to learn about this topic.
Low-Angle Bevel-up block planes are great for a variety of tasks, but only with the correct blade bevel. Knowing which blade bevel to use for which job will vastly improve your making experience. Check out the page to learn more.
I’m working away on the Best Practises page. While you wait for those, I have added to the Best Practises page an index of the Youtube videos by Davide Sora (website). Davide is an award winning violin maker for aesthetics and tone. Davide and I clearly have the same philosophy in violin making, clean, neat and traditional hand made violins.
Check out the latest addition to the ‘Best Practises’ page: I’ve added a section on glues. Here are some interesting tidbits:
- Hide glue is made from the same process which produces food gelatine (Jello), but gelatin is not the same as hide glue.
- Similar animal glues have been in use for about 6,000 years.
- White and yellow “carpenter’s” glue were only invented in the early 20th century.
- Additives of urea, salt, glycerine and vinegar to hide glue modify the glue, some with detrimental effects.
- There is an additive that prevents liquid hide glue from gelling.
I also discuss briefly the preparation of hot hide glue, the interpretation of various glue ‘bloom strengths’, and where these are typically employed.
An interesting aside: ‘Bloom’ refers to both the expansion of the dry hide glue when it expands and also the “Bloom Strength” which is actually named for the inventor the gel strength measurement device: the gelometer, seen on the right. Invented and patented by Oscar T. Bloom.
Davide Sora won Bronze in the 14th Cremona violin-making competition (Concorso Triennale di liuteria) along with the special prize for “the violin with the best acoustic quality” from the Union of Polish Violin Makers, He’s posting some pics of his winning violin on Maestronet. It’s a beauty.
Davide noted his violin is made on the Stradivarius ‘G’ Form. He also tells us that the varnish of this violin is made with raw shellac, a bit of mastic and naturally oxidized linseed oil (linoxin), its essentially an alcohol solvent varnish, which is his standard varnish. “The color is given in part from the resins and in part from madder lakes fixed on alum and iron.”
As one reader pointed out the shape of the kidneys of the bridge are not the typical US/UK ‘egg’ shape. He says “In fact I prefer more elliptical kidneys and oriented in the diagonal sense, mostly for aesthetic reasons but also because I believe that more effectively lighten the top area of the bridge under G and E strings, helping to give a more open tone and fast response. The pointed shape at the waist … is not my standard practice, but it derives from the ‘fine tuning’ for this violin in particular.”
The finish is not antiqued. The regulations for this competition forbid antiquing of wood or varnish or breaking from Tradition in ‘form, decoration, color, or woods’. Basically, a violin in the tradition of the Cremonese makers 300 years ago.
He also reports that the top plate has an approximate density of 0.40 and a final weight of 62 gr with bassbar and a M5 resonance at 373 Hz (F#). The back plate has a density of 0.57, a weight of 95 gr and M5 at 371 Hz (F#). He says “Usually I don’t match the modes, but this time they came in this way, for what it’s worth.” The top plate has an arch height of 16,5 mm and the back pate has an arch height of 15.8 mm measured before inside hollowing.
You can hear two of Davide’s past violins here (a 2008 and a 2011).
The Cremona Museo Del Violino has published the winners of the “Concorso Triennale Internazionale degli Strumenti ad Arco “Antonio Stradivari”“, which they describe as the “Olympics of Violin Making”, and with 445 instruments submitted by 334 makers from 31 countries, you can see why. As well, of all the categories, only a single gold was awared.
Canadian Viateur Roy took the silver prizes for Violin and Cello! (no Gold was awared in either case). Davide Sora won Bronze for Violin (check out his amazing YouTube videos) that went well with his special prize from the Polish Union of of Violin Makers, for the violin with the best acoustic qualities!
Today marks the 4ths year of the StephenChurchill.com site. I’ve tried to make this site a useful reference for violin makers. I’m thrilled to report that we’ve had 32,080 hits to date and visitors from over 120 countries!!
Thanks to everyone who’s provided feedback, I hope you find this site useful in the future as I expand the content and make the site even more useful to my fellow makers!
Check out this article on Dendrochronology from The Strad. The article reviews how this wood dating technique is used to verify the authenticity of instruments. From an instrument making point of view, the method has shined light on the age of wood used to make instruments:
“The science has also provided valuable information to modern makers: the patterns of use of specific trees from specific forests by different luthiers in different locations; the trees shared by makers in different countries; the use of relatively fresh rather than long-aged wood, and so on. All these findings shake up tired ideas about ‘Little Ice Age’ wood and bizarre seasoning techniques. “