A really good help is to burnish the underwrap after it is applied, that will smooth out the underwrap so that you have less worry with the ridging of the threads with your guide wrap. i use a very highly polished long and narrow stone and it does a wonderful job. I would not epoxy the under wrap prior to installing the guide. The only concern, and the reason most manufacturers do not do a lot of underwrapping is the lack of ashesion between the final wrap and the rod.