Here is a comprehensive writeup about the process and halachic explanations written by @Yisrael.Kleinhendler and published in the http://www.hakirah.org - The Flatbush Journal of Jewish Law and Thought.
http://www.hakirah.org/Vol19Kleinhendler.pdf
Silk Screen Sefer Torah by Yisroel Kleinhendler.pdf (456.6 KB)