I've used mc before to bond two different colors of unryu. You might be interested in checking out videos of a panel on back-coating from this year's Centerfold Convention with Dr. Lang, Malachi Brown, Jared Needle, and Jon Tucker:
https://www.facebook.com/centerfoldorigami/videos/504280936393061/ https://www.facebook.com/centerfoldorigami/videos/504293596391795/ https://www.facebook.com/centerfoldorigami/videos/504315749722913/ Michael http://havepaperwilltravel.blogspot.com/
