Preposterous though it may seem at first sight to propose solutions for problems solved at least a century ago, we could not refrain from doing so. A certain lack of unconditional reverence for the past, together with some independent thinking, may have led to this condition. That said, don't expect real inventions, that didn't exist up to now. Though I am not aware of an octagon marker for bows being marketed, the other tools and accessories do exist, but in a form or quality that left things to be desired. The purfling chisel is an example of an absolutely not shocking modification of an existing design, so much so that I would be surprised if it hadn't been invented by at least a score of colleagues. The double-bass tuners are an example of a search for quality, mechanical and aesthetic, that I couldn't find combined.
Apart from the octagon marker, that went into limited production after 3 years of experimenting, the other solutions proposed here have stood the test of between 15 and 25 years of use. In the separate descriptions I will discuss in detail the problems we met and how we think to have contributed to a solution. When relevant the descriptions will be completed by manuals for use or fitting.
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