I was looking at thread the other day on the FilTec (glide thread) site and came across this:
http://www.bobbincentral.com/accesso...e-erasers.html
says it gets blue lines out forever. I have not used them much, but am planning to try them. Alot of the longarmers I chat with swear by them...I have been leery. Let us know if you try this and like it. I would be interested.