Hello all...some observations on the use of proteins
Pro. Protein based sealants...egg white, vernice bianca, hide glue, egg white, etc. are excellent sealers. Nothing penetrates the layer if properly applied.
Con. I have not seen in my own experiments using these materials or on the work of any other violin maker who used a protein sealer the deep illumination or protective qualities which characterize the "Cremonese ground".
When the work of Brigitte Brandmaier and J P Echard came out, I did a bit of research. I was fortunate to have the help of two violin makers who had industrial testing backgrounds. Here is what we found.
The testing methods used in both studies were impeccable. Given that, what do we make of the findings?
We were fortunate to enlist the help of a group of technicians who have working experience with the analytical methods. They examined the findings and then shared their experience:
The Brandmair study found the presence of amino acids on the surface of the instruments studied. Amino acids are markers for proteins. As they explained, these testing methods are so sensitive that they suit up and then put gloves on in a vacuum chamber before doing the procedures. Otherwise the mere presence of a human being in the room will make the sample test positive for protein. The conclusions they shared went this way: Yes proteins were present. However it is not possible to distinguish the source...could have been residue from eggs you had for breakfast, random toe nail clipping residue, glue residue ....but the most likely conclusion was that this surface was made by human beings.
on we go,
Joe