The Clown's Corner
LONGHIN - Great Tube Testers from Italy
Treatment of Wood / The Queen of laquers: Shellack
This may not be a very relevant little feature with respect to the sound of speakers. But still: Some of you might enjoy it.
The Japanese and Chinese are undoubtedly the masters of laquers (Japanese Urushi for example). But in Europe, too, there are historical techniques and materials and receipes, dating back centuries. One example is shellack. Shellack is a secretion of a louse (zoological: scale) resident in South East Asia and India. The exact latin name of the shellack producing scale is "Kerria Laccifera". It takes around 300.000 (!) of those tiny creatures to produce one kilogramm of the dried flakes and plates. Shellack has been used since centuries as varnish for paintings and furniture of the Baroque era; some sources say that it has been used even since the 16th century in Europe. It was also a very important material in the mid 1920s for the production of records! Vast quantities of shellack have then been processed to those 78 rpm discs.
Nowadays the use of shellack is almost extinct. Modern nitro cellulosis or DD 2-component-varnishes have taken over. There are two reasons for this. First: Modern varnishes are more durable in terms that they are resistent against water stains, some even against acids or vodka. Second: The application of a high quality shellack polish is difficult and takes a lot of time and patience.
To produce a closed grain high gloss shellack polish means to apply hundreds of ultry thin layers. The lesser the viscosity of shellack the better although it prolongs the polish even further. You can buy ready to use shellack; I mix my own shellack. The flakes are dissolved in Ethanol (99,9% Ethanol! If you use barbecue lightening spirit you have at least 4% water in it - this reduces the quality of the polish to a considerable extent!). Once the flakes have dissolved - this takes about 12 hours - the liquid must be filtered. Ladie's nylon stockings are excellent filtres. The liquid shellack is then applied to the wood with a brush four or five time, depending on the viscosity. It takes hours, if not days, between the layer. In a humid surrounding (on a cool rainy day) drying of the individual layers takes much longer than in a warm and dry surrounding. Between each layer the surface must be sanded. At a certain point the use of a cotton bale filled with raw sheep wool which is drained with shellack starts. Beginning with small "8"-shaped movements - vertical, diagonal to the left, diagonal to the right - then big "8" shaped movements and so on...
It takes years to learn how to do it, to be able to judge the surrounding climate, to be aware that resting the bale for the fraction of a second too long on the polish will tear the underlying layer open.
WHY do a shellack polish? Because of the beauty of it. No matter if it is an "open grain" (just little glossy effect) or "closed grain" (high gloss effect) it looks and feels totaly different from modern days varnish glosses. It is ALIVE.
Ruby Shellack flakes
Lemon Shellack Flakes
Lemon Flakes dissolved in WHAMM
First Step: Brushing along with the Grain
The Bales, big one and small one
Applying Shellack with Bale
Principle movements of the Bale
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