Here in the UK I buy 5/16" (seems best fot for the shafts I buy) paralllel fit piles for my bamboo arrows. I scrape the outer rind down on my bamboo arrows until the shaft fits tightly in the pile, and glue together using two-pack glue. I dont use plugs at the pile end, but I do use plugs of scrap osage at the nock end, again glued in with two-pack adhesive, before I cut the self nocks into the shaft.