Michael_Molnar

An enormous issue with CNC'ing is the rapid generation of dust and chips. I built a dust cabinet around mine which is connected to a large dust collection system.

I am confused (again). To the varnish makers in this thread: Are you trying to develop a superb varnish that looks Cremonese (or even better), or are you recreating the Cremonese methods? For example, cochineal is historically valid as a colorant because it was detected. Fine. But how it was fixed as a pigment in the varnish is just as important if you want an historically valid result.

Exactly right, Nick. I find more makers are using CNC parts but do not want to draw attention to that "heresy" as it were. FYI, wood moves as it is machined, so there really is no such thing as perfect replication. However, it takes the drudgery out of making IMO. I then have more time learning workmanship skills. Still trying.

Congratulation, Don, on winning a Certificate of Merit for Viola Tone at the Cleveland VSA.

Yes, because more rosin is exposed to air. It also prevents "frozen skins" from forming. Another benefit is the avoidance of hot spots where rosin or varnish can burn.

Here is the stirring mechanism; https://www.amazon.com/Mophorn-Electric-Overhead-Stirrer-Mechanical/dp/B06W2HNPPP/ref=pd_lpo_vtph_469_lp_t_2?_encoding=UTF8&psc=1&refRID=TGPES76PBKKT50ZP288K

Felt better yesterday, so I cooked some burgundy varnish. I have a short movie on Facebook showing how the stirring rate varies.

Laser printers make very permanent labels. The paper should be acid free for archival quality. I bought a lifetime supply of Japanese paper years ago. Google around and research this.

Thanks for those GREAT photos.

The tin atom attaches to the cochineal molecule (anthraquinone - carminic acid). The charge on the tin atom (ion) twists or distorts the molecular structure, which in turn changes the light absorption property. Magenta means that the molecular structure now absorbs more blue, green (cyan) and yellow. Aluminum in alum distorts the molecule to absorb more blue and green and less yellow, producing red for which carmine is best known. You need to look at a color wheel to understand how colors are produced by absorption. The details, nevertheless, remain a puzzle, but I am sure there is somewhere a graduate student working on this for her dissertation.

Which form shape are you testing?

I hear he was terrible at golf.

I wonder whether Stradivari (and other makers) noticed the weakness of slab-cut backs and moved to quartered backs. The slab cuts need to be thicker and thus presumably heavier.