As above. . . I tend to do all this in one spot in my basement shop and I use the wall at that location to push against. I hold the broadhead with a pliers, push against the wall and twist the shaft until the nock is in alignment as I want it, then immediately spin it on the work surface. If good to go, I plunge the head into a small container of water to cool (if hot melt glue was used) and set it against the wall, then go on to the next one. If it doesn't spin, I keep twisting and pushing.
ChuckC