I tend to agree with John "putting varnish on the blank to protect it from a bead head would be the same as putting a piece of paper in front of a deer to protect it from a 30-30 round."
I have completely finished a glass blank with varnish due to the fact it was a rebuild and the finish was just worn out and quite unpleasant to look at. I would not recommend for a new blank, but one that is old and being rebuilt can end up looking very nice with a full coat - if applied properly.
I wrapped the guides and finished the guides 2 coats first and then put the third coat on the entire rod - it turned out really nice.
Good Luck with the new build.
Let No One Walk Alone
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