Epoxy is used on graphite/glass rods. It can be between one and three coats depending on how thick it is applied. I have built bamboo rods from preformed blanks although I am certainly not a professional in this area of rod construction. After much consultation with known builders I chose to use spar varnish. Be advised that varnish is much thinner than epoxy. It should be applied to the rod while it is in a turner of 18-20 rpms and monitored for sagging. Varnish takes much longer to dry. Apply it thinly and build it up to the desired appearance with several coats(maybe 5-10 depending). This is time consuming as I usually only do one coat per day. And yes the finish in the photo appears very thin.