Hans Weisshaar was an important American violin

Violin

The violin is a string instrument, usually with four strings tuned in perfect fifths. It is the smallest, highest-pitched member of the violin family of string instruments, which includes the viola and cello....

 restorer

Luthier

A luthier is someone who makes or repairs lutes and other string instruments. In the United States, the term is used interchangeably with a term for the specialty of each maker, such as violinmaker, guitar maker, lute maker, etc...

.

He worked in Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, Switzerland

Switzerland

Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

 and Holland before coming to the United States in 1937, where he was employed with Simone Sacconi at Emil Herrmann

Emil Herrmann

Emil Herrmann was a prominent dealer and restorer of violins in New York City. Nearly all of the most famous instruments passed through his hands at one time or another of his career including literally hundreds of made by Antonio Stradivari, Jakob Steiner and the Amati, and Guarneri families...

 in New York.

In 1947 he moved with his family to Hollywood, California, where he established his own business. He gained a reputation as an expert in the field through extensive teaching, lecturing, and judging in international competitions.

In 1988 he published with Margaret Shipman his "Manual for Violin Makers", a work devoted to violin restoration.