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Since my posts are being moderated for an indefinite period of time, I may not be able to respond to you via Pegbox postings as quickly as you would prefer. However, you can always PM me or email me at Brian.McLinden@gmail.com First, to introduce myself in detail: I studied making but did not graduate from the Warren School. Four violins told me that I would never cut it as a maker. Nonetheless, the mysteries of finishing caught my technical fascination. I obtained a BS in physics from Hobart, then a BS in engineering mechanics from Columbia. Next I was as an informal student with George Frank, a fine finisher of very considerable reknown, during his retirement years in Florida. See his books. He encouraged me to explore even the wackiest of ideas, like alkaloids and phenolics. After self-teaching in thin films materials engineering, I bought more and more into wood mineralization and became more and more questioning of what I was reading elsewhere about wood finishing in relation to violin grounds. I read an English draft of Sacconi and then Ralph Iler's work on silica, silicic acid, and silicates. An interest in early wood preservation led me to plant substances. I've been considering what materials might be synthesized from them through catalysis during the procedure of ground formation. I'm mostly a theory guy. On the other hand, you are practitioners, and to you theory is perhaps a massive bore. Are we always to be like oil and water? Most of you are running tests all the time, indeed every time another piece of wood comes to your bench (Strad did this), while only occasionally do I run a critical experiment. If intuition tells you that whatever I offer could benefit you in that pocket of yours, why not run your own tests? Any posted word or picture from me will never satisfy you, not any of you, not ever. Only your own first-hand bench experience will truly persuade you. I'm into sharing. Angel has indicated this. We love to argue. Fellows, as a finisher with a theoretical bent I enjoy collaborations with makers. I would not like to be thought of as uncaring or as a control freak. Why not take what little of my stuff you like, then adapt that to what works for you in your own circumstances? Second, concerning the formation of highly elastic ground systems: Unlike most of his readers, I have taken most seriously Sacconi's oh so casual mention of the "glassworks." Pursuing that line of thinking has resulted in the highly penetrating "wax polish" that I offered to you recently. It is not only resinous but silicon-based. It may be timely to recall that in the medieval glassworks, diverse recipes of very thin films were alternated and fired in order to build up, step by step, stained glasses with their surpassingly beautiful shimmering optics. Also recall that in nature, thin films are alternated to give beautiful optics. For example, irridescence in the shell of the mature beetle. Could makers today benefit from exploiting these facts? To obtain beautiful optics in the ground system, I therefore suggest alternating resinous/silicon films and sugar films with properly applied flame polishing. Here are some things that motivated this proposal: From my notes - “I combined some sugar and some aluminum chloride solution from the drugstore in a glass of hot dilute waterglass, only to discover a spectacular rainbow of colors when looking through the tilted glass to the afternoon sun.” Also, http://books.google.com/books?id=wIuuAwAAQBAJ&pg=PA195&lpg=PA195&dq=%22aluminum+chloride%22+terpenes&source=bl&ots=aAr2l4vJak&sig=0XGd-RFUUJhD5iwD3eEwCSc9Iso&hl=en&sa=X&ei=xg82VJWLGYaYyATpjIJg&ved=0CC8Q6AEwAg#v=onepage&q=%22aluminum%20chloride%22%20terpenes&f=false Also, http://fshs.org/proceedings-o/1954-vol-67/193-194%20%28SCHULZ%29.pdf Multiple thin films with alternation will produce novel optical effects. That is why I disagree with Bruce Tai when he says, "It is almost inconceivable that wood finishes would possess ordered structures that generate interference colors." See his "Dichroic effects?" section on page 11-12 of https://45728c79-a-62cb3a1a-s-sites.googlegroups.com/site/taiviolinproject/JVSA_Tai_published_part2.pdf?attachauth=ANoY7cpVrVlPo8DvR_IlQB0AsimvJYDfRqT815RRNPrMsawwqmLzxCVwl9fOu6GzK5LHhy3UHtKNb_p_G-3FZZwBaA3drg7tO-zKhYif2z0_iTdyPnMyJY3jCiIRPX6lyZBIPE0rreBB3UilR6vP5KtGcAweByuzlbuxm7AF_LMmFpF4HU7J6fw6Dvxq5pFFVE8EfB1k482arx21v96O6-docU3Ou4KhbfiZN9J2cOE47ncZNe0yylo%3D&attredirects=0 otter
Per scientific studies, the goals and evolving practices of at least a few Italian masters were such as to account for the confirmed presence of very large amounts of silicon in their ground systems. How, and even more importantly why, did silicon serve Italian goals and get so DEEPLY into the master woods? To my knowledge these two questions remain unanswered. Addressing here the lesser question, the “how,” here is a suggestive scheme: Soak powder of lemon peel, and various other plant substances, in turpentine Boil beewax (never oil) in potassium silicate, then to this fresh preparation add the highly penetrating turpentine mixture Beforehand, extract various other plant substances by simmering in vinegar. Add tartar (cleaner, brightener) and ammonium chloride (will precipitate KCl). With rapid stirring, combine the freshly prepared turpentine/silicon mixture with the vinegar/salts mixture. Keeping everything agitated by using capped glass jar, keep dipping the pad and work this wax polish onto the scraped wood very fast. Pass the work back and forth near a fire. Burnish the work just “flame polished.” Keep reapplying procedure in areas where needed. otter Note – plant substances and ammonium chloride account fully, IMHO, for the high nitrogen content seen in master grounds. Equisetum smoothing or protein sizing has never made sense to me for grounds.